Preliminary Program Plan FY 2007

NATIONAL RADIO ASTRONOMY OBSERVATORY

Preliminary

NRAO Program Plan FY 2007

Draft: 09/27/06

Cover Image: A composite image of the Galactic plane near W28: blue (VLA λ = 90 cm), green (SGPS+VLA λ = 20 cm), red (MSX λ = 8 µm). Image courtesy of Crystal Brogan (NRAO), Joseph Gelfand and Bryan Gaensler (CfA), and Namir Kassim and T. Joseph Lazio (NRL). Table of Contents

Executive Summary...... i A. Observatory Review...... 1 B. FY 2006 Review...... 5 1. Science Highlights in FY 2006...... 5 2. FY 2006 Technical Highlights ...... 10 C. Science Programs for FY 2007 ...... 11 D. ALMA Construction ...... 18 E. EVLA Construction...... 38 F. Telescope Science Operations ...... 45 1. North American ALMA Science Center ...... 45 2. Green Bank Telescope (GBT) ...... 48 3. Very Large Array (VLA) ...... 54 4. Very Long Baseline Array...... 60 G. Technical Capability Development...... 65 1. Central Development Laboratory Summary...... 65 H. New Initiatives ...... 79 1. The Square Kilometer Array (SKA) ...... 79 2. The Long Wavelength Array (LWA) ...... 79 3. The Frequency Agile Solar Radio Telescope (FASR)...... 80 4. Space VLBI...... 80 I. Community Support Programs ...... 81 1. End to End (e2e) Operations ...... 81 2. Scientific Community Outreach ...... 84 3. Spectrum Management...... 86 4. Education and Public Outreach...... 87 J. Management and Infrastructure Services...... 93 1. NRAO Organization...... 93 2. Administration...... 96 3. Computing and Information Services (CIS...... 103 4. Program Management Office (PMO) ...... 105 K. FY 2007 Preliminary Financial Plan...... 109 Appendices...... 116 A. Scientific Staff Research Activities ...... 116 B. Research Staff...... 141 C. Management Staff...... 147 D. Committees...... 149 E. Acronyms and Abbreviations...... 153

Program Plan FY 2007

Executive Summary

In FY 2007 the NRAO will continue to operate the GBT, the VLA, the VLBA, and its technology research center, the CDL. The GBT azimuth track will be extensively refurbished. The wide-bandwidth Zpectrometer, the Caltech Continuum Backend, and the Penn Array bolometer camera will be completed and tested on the GBT. New dynamic-scheduling tools will enhance observing efficiency, and pointing/surface improvements will increase high-frequency performance. The VLBA correlator will be upgraded to accept 17 Mark 5 disk-recorder inputs, the High Sensitivity Array will be converted to Mark 5 operation, and the VLBA tape-recorder system will be retired. In order to maximize scientific returns, the NRAO will encourage large key and legacy projects by changing its model for allocating observing time.

Construction milestones for the Expanded Very Large Array (EVLA) include making eleven EVLA antennas with new frequency coverage available to observers and the first on-sky tests of the EVLA prototype correlator.

ALMA construction will proceed under the new funding and schedule baseline that calls for completing the Array Operations Site (AOS) Technical Building, acceptance of the first Vertex antenna at the Operations Support Facility, delivery of the back-end racks for the first antenna and the first three front ends, installation of the first quadrant of the correlator at the AOS, and first fringes on an astronomical source in 2007. The NRAO will help to develop a revised ALMA operations plan for review by the ALMA Board. The NRAO will also submit a proposal for ALMA North American operations, including the NAASC, to the National Science Foundation.

The NRAO will expand its community support programs. The e2e Operations initiative will systematically enhance support services for observers. The NRAO will begin planning for an observatory-wide Integrated Science Center to deliver uniform high-level support services to users of all NRAO telescopes in the most cost-efficient manner by utilizing the expertise and economies of scale available throughout the NRAO. The first VLBA student-support stipends will be awarded. The NRAO will work with the community on the Square Kilometre Array, other telescope developments, and planning for the next decadal survey.

This FY 2007 plan is based on the Presidential Request Level budget of $50,740k for NRAO operations, EVLA construction, and ALMA operations (including $2000k carryover from FY 2006). The ALMA construction plan is based on the $64,270k rebaselined funding level. The NRAO Program Management Office will continue to implement the Web-Based Business Services (WBBS) system to modernize project management, improve the timeliness and accuracy of all business information, and closely monitor the progress and costs of large projects.

A. Observatory Review

FY 2006 Review

Science: Science discoveries during the past year were impressive, and included the identification of short-duration GRBs; the detection of CO from galaxies at z ~ 4; a water giga-maser from a Type II quasar at z ~ 0.66; the fastest-spinning millisecond pulsar (1.397 ms period); the most accurate measure of the distance to the Perseus spiral arm (previously known only to within a factor of two); a cold, extended dust disk suffused with centimeter-sized pebbles around a nearby star, indicative of the earliest stages of planet formation; a huge hydrogen superbubble rising out of the plane of the Milky Way; and the detection of additional pre-biotic interstellar molecules that provide information on the formation mechanism of large molecules.

ALMA: The ALMA project team successfully concluded a comprehensive and intense round of reviews of scope and cost leading to a new baseline. Cost reviews by an international panel were held in Garmisch, Germany in October 2005 and in Washington in late January 2006. In early February in Charlottesville, the NSF convened a panel of experts for a comprehensive management and cost review of the North American portion of the ALMA Project. The NSF panel report validated the technical readiness, the current project management, the cost estimates (except for a concern that the contingency may be too small), and endorsed the viability of the rebaselined ALMA project. In May, the National Science Board accepted the recommendation of NSF Director Bement to proceed with a 50-antenna version of ALMA (with an increased contingency). Congressional action on the NSB recommendation is pending. The AOS Technical Building was completed. The antenna contract was initiated. Local labor plans and procedures were developed and implemented.

EVLA: By the end of FY 2006, six antennas will be outfitted with EVLA electronics and released for use by observers. Progress on the WIDAR correlator by our Canadian collaborators is proceeding. At its midpoint, the eleven year project is 9–12 months behind schedule, but with an expectation that some of that time can be regained through accelerated antenna outfitting. At this point, successful prototypes have been completed for nearly all electronics modules which allows full construction to proceed. The EVLA Advisory Committee and an NSF mid–project review panel met in May 2006 and expressed confidence and general satisfaction with the projects. Recommendations of the review groups were very constructive and tractable, and will be addressed in the coming year.

GBT: The Green Bank Telescope operation matured significantly over the past year. Downtime from faults diminished to 1–2 percent and time available for scheduled observations approached 70% of total time in the year (24/7/365 basis). The telescope was made significantly easier to use by the introduction of the Astrid scheduling block user interface, which is consistent with Observatory–wide software objectives.

VLBA: Mark 5A disk–based recording systems are now installed at all 10 VLBA stations plus the GBT, which often participates in VLBA projects. The Mark 5 systems have reduced operations and maintenance costs by replacing the tape recording systems and have also improved sensitivity through higher bandwidth recording.

End-to-End Operations: Following the recommendations of the NSF Software Review panel (September 2005), the NRAO appointed a dedicated team to manage the Observatories e2e operations initiative, which will make the NRAO telescopes and data products easier to use by non-experts and

Program Plan FY 2007 A. Observatory Review 1

experts alike. The Assistant Director for e2e Operations (Radziwill) and Principal Scientist (Fomalont) have already developed an organization and detailed plans for the initiative and work is underway.

Management: One of the major management accomplishments last year was the completion of the senior management team hiring and reorganization. Over the past 18 months, appointments have been made for Deputy Director (Jewell), Associate Director for Administration (Clark), NRAO ALMA Project Director (Russell), Assistant Director for Green Bank Operations (Prestage), the new EVLA Project Manager (McKinnon), the new Head of Division of Scientific and Academic Affairs (Frail), the Assistant Director for e2e Operations (Radziwill), and the Head of the North American ALMA Science Center (Carilli), and Observatory Technical Leader (Fisher).

Administration: The new administration team has introduced monthly “flash reports” which provide status snapshots of all Observatory accounts. The flash reports provide an early warning system for potential overruns or underruns so that corrective action can be taken promptly. A new budget development cycle provides a rational process for building and justifying budget expenditures.

FY 2007 Overview of Plans

The NRAO’s overarching goals for FY 2007 are

1. Continue efficient operation and maintenance of all three existing telescopes, the GBT, VLA, and VLBA. 2. Proceed with ALMA construction according to the recently revised funding and schedule baseline. 3. Complete the ALMA Operations and NAASC proposal for review by the NSF. 4. Proceed with EVLA construction and implement the key recommendations of the recent Advisory Committee and Visiting Committee reports. 5. Ensure the success of the new e2e Operations Division and proceed with the division’s development plan 6. Develop a concept for an NRAO Integrated Science Center. 7. Increase the fraction of observing time available for legacy and key observing projects. 8. Work with the community on SKA and new generation radio telescope development.

Some of the more significant, specific goals for each of the NRAO’s telescopes, projects, and laboratories are summarized here. These goals and others are described in more detail in the chapters that follow.

Telescope Operations • Continue efficient operation and maintenance of all three existing telescopes, the GBT, VLA, and VLBA

ALMA Construction • Accept the first Vertex Antenna a the OSF • Finalize the agreement between AUI and NINS / NAOJ • Develop and implement a plan to co-locate the ALMA Central Office and the NA Executive offices in a new location in Santiago

Program Plan FY 2007 A. Observatory Review 2

• Hire staff in Chile for the JAO • Complete construction of the AOS Technical building and the enlargement of the ALMA camp and Contractor’s Camp • Complete and deliver the first three Front Ends • Deliver the Backend racks for the first antenna • Install a quadrant of the correlator at the AOS • Demonstrate two-antenna interferometry on an astronomical source at the ATF. • Refine the ALMA Operations and North American ALMA Science Center plan and present in a proposal and NSF review.

ALMA Operations • Submit a revised ALMA operations plan for review by the ALMA Board • Submit a funding proposal for ALMA North American operations and the NAASC for NSF review • Work with the E2E Operations Division on ALMA requirements for the Archive and VO development

EVLA Construction, VLA / EVLA Operations • Proceed with EVLA construction following the recent recommendations of the Advisory Panel and Visiting Committee • Offer new frequency coverage of EVLA systems to observers • Return 11th EVLA antenna to the array (by end of FY 2007) • Replace 4000 railroad ties • Conduct the first on-sky tests of the EVLA prototype correlator • Develop and prioritize science requirements and observing modes

GBT • Complete Azimuth Track remediation project • Complete construction and initial science validation on the Zpectrometer wide bandwidth spectrometer • Complete construction and initial science validation of the Penn Array bolometer camera. • Develop and implement initial dynamic scheduling tools. • Complete servo improvements and other Precision Telescope Control System (3 mm observing capability) initiatives.

VLBA • Complete the conversion of the High Sensitivity Array to Mark 5 operation • Complete the conversion of the correlator to 17 Mark 5 inputs and retire the tape drive system • Initial VLBA student support stipends awarded • Saint Croix station rust-proofing project begins

Program Plan FY 2007 A. Observatory Review 3

End-to-End Operations • National Virtual Observatory Project targets o Complete initial draft of the Cone Search specification o Complete initial draft of the Simple Image Access specification o Complete initial draft of the Simple Line Access specification o Complete prototype of the scalable data analysis framework

• NRAO Archive Infrastructure and Interface targets o Acquire and install ESO / NGAS Archive Software, and integrate into existing NRAO science data archive o Develop second generation archive interface prototype o Complete transfer of historical VLBA tape archive and GBT science data to new archive o Transfer the NRAO proposal submission tool and data base to e2e Operations

• Automated Data Processing targets o Meet all milestones for CASA development o Complete pipeline prototype reductions o Begin working through VLA data archive using the image pipeline

Integrated Science Center Development • Develop and document concept for an NRAO Integrated Science Center

Science Programs • Schedule first Legacy / Key Project proposals from October 2006 proposal call

Education and Public Outreach • Complete the 2nd Annual NRAO Image Contest and announce winners • Review Web renovation and O&M plan; hire a new WebMaster • Proceed with development of new Science and EPO web sites • Proceed with collaboration on ALMA EPO

SKA / Future Radio Telescopes • Collaborate with the community on the development of SKA and new generation telescopes for the upcoming Decadal Review.

Program Plan FY 2007 A. Observatory Review 4

B. FY 2006 Review

1. Science Highlights in FY 2006

Measurements of the Zeeman Effect

Robishaw and Heiles have used the GBT to observe the λ = 21 cm hydrogen line along two strips crossing the major axis of a molecular filament in the Orion molecular cloud. They detected significant Zeeman splitting at almost every position and find that the line-of-sight magnetic field reverses direction across the axis of the molecular cloud (Figure B.1). These observations are consistent with lower- resolution detections made using the Hat Creek 85-foot telescope. Stellar polarization data show that the plane-of-sky field is nearly perpendicular to the cloud’s major axis. This, in addition to the opposite directions of the line-of-sight fields above and below the cloud, suggests a helical magnetic field structure. MHD simulations of filamentary molecular clouds have been able to reproduce just such a helical magnetic field structure. The line-of-sight field strengths in this region are at least 10 microGauss, corresponding to a pressure of at least 30,000 K cm−3; this is comparable to the pressure from the hot gas that permeates the Eridanus loop. A long-standing theoretical construct maintains that high-mass star formation is moderated by magnetic fields: regions of massive-star formation should possess low fields for gravitational instabilities to dominate. However, observations, including these GBT results, have shown just the opposite. The Taurus molecular clouds are devoid of high-mass star formation yet exhibit upper limits on magnetic field strengths of less than 8 microGauss. In Orion, a site of high-mass star formation, line-of-sight fields larger than 10 microGauss in emission were found throughout the region.

Investigators: T. Robishaw, C. Heiles (UC Berkeley).

Figure B.1. The Orion Molecular Cloud superimposed on the Orion constellation, with the orange star Betelgeuse at the top center. The inset shows the Slinky-like coils of the helical magnetic field surrounding the filamentary cloud. (Credit: Saxton, Dame, Hartmann, Thaddeus; NRAO/AUI/NSF).

Program Plan FY 2007 B. FY 2006 Review 5

Closest Pair of Supermassive Binary Black Holes

Astronomers using the VLBA have discovered a black-hole binary in the radio galaxy 0402+379 (z = 0.055) with a combined mass of 1.5×108 solar masses and a separation of only 7.3 pc. This is closer by more than two orders of magnitude than any other known supermassive black-hole pair. It has implications for how galaxies form and evolve, and it provides constraints for the success rates of experiments designed to detect gravitational waves from black-hole mergers.

Investigators: C. Rodriguez (UNM), G. B. Taylor (UNM), R. Zavala (USNO), A. Peck (CfA), L. Pollack (UCSC), R. Romani (Stanford).

Constraints on Changes in Fundamental Constants from a Cosmologically Distant OH Absorber or Emitter

Kanekar et al. have used the GBT to detect the four λ = 18 cm OH lines from the z ~ 0.765 gravitational lens toward PMN J0134−0931. The 1612 and 1720 MHz lines are in conjugate absorption and emission, providing a laboratory to test the evolution of fundamental constants over a large lookback time. Kanekar et al. compared the HI and OH main-line absorption redshifts of the different components in the z ~ 0.765 absorber and also the z ~ 0.685 lens toward B0218+357 to place stringent constraints on changes in the 2 1.57 quantity F ≡ gp[α /µ] , where α is the fine-structure constant and µ is the electron-proton mass ratio. They obtain [∆F/F] = (0.44±0.36stat±1.0syst) × 10‐5, consistent with no evolution over the redshift range 0 < z < 0.7. The measurements have a 2σ sensitivity of [∆α/α] < 6.7×10‐6 or [∆µ/µ] < 1.4×10‐5 to fractional changes in α and µ over a period of ~ 6.5 Gyr, half the age of the Universe. These are among the most sensitive constraints on changes in µ.

Investigators: N. Kanekar, C. L. Carilli, and G. I. Langston (NRAO), G. Rocha (Cavendish Laboratory), F. Combes (Observatoire de Paris), R. Subrahmanyan (Australia Telescope National Facility), J. T. Stocke (University of Colorado), K. M. Menten (Max‐Planck‐Institut für Radioastronomie), F. H. Briggs (Australia Telescope National Facility and Australian National University), and T. Wiklind (Space Telescope Science Institute).

VLA Identifies Afterglow of Short Gamma Ray Burst in an Elliptical Galaxy

Using the rapid-response observing mode put in place in 2005, the VLA was used to unambiguously identify the afterglow of the short “hard” gamma-ray burst GRB050724 detected by the Swift satellite. The identification of the radio afterglow of this burst showed its association with an elliptical galaxy at redshift z = 0.257. The association with a galaxy that is dominated by an old stellar population provides key support for the model in which two compact stellar remnants in a binary system coalesce, giving rise to the gamma-ray burst and the relativistic fireball.

Investigators: E. Berger (Carnegie Observatories) and 23 collaborators.

VLA Low-frequency Sky Survey Observations Completed

The VLA Low-frequency Sky Survey (VLSS) is a 74 MHz survey of the entire sky above −30 degrees declination, or about 75% of the celestial sphere. An allocation of 700 hours of observing time has enabled this survey to cover more than 500 fields with a combination of 80" resolution and 0.1 Jy noise level. This combination of resolution and sensitivity is unparalleled in any other low-frequency survey, due in large part to the excellent VLA imaging capabilities that reduce the impact of confusing sources.

Program Plan FY 2007 B. FY 2006 Review 6

About 95% of the fields have now been imaged and may be seen in the second major data release, (see http://lwa.nrl.navy.mil/VLSS). About 67,000 sources have been identified to date. All sky maps and the source catalog are available via interfaces similar to those used by the NRAO VLA Sky Survey. The VLSS is expected to be a resource for all astronomers for many years to come, with potential discoveries of fossil radio sources and very distant galaxies still lurking in the data.

Investigators: R.A. Perley, J.J. Condon, W. D. Cotton (NRAO); A.S. Cohen, W.M. Lane Peters, N.E. Kassim, T.J.W. Lazio (NRL); and W.C. Erickson (University of Maryland).

VIVA, a New HI Survey of the Virgo Cluster

VLA Imaging of Virgo in Atomic gas (VIVA) is a VLA Large Project that has been observing during the past two C configurations. This survey has now imaged the neutral hydrogen (HI) emission from 50 galaxies in the Virgo cluster with sensitivity, angular resolution, and velocity resolution that are factors of 3–5 better than a similar VLA survey carried out nearly 20 years ago. A wealth of galaxy morphologies has been found. In several galaxies, there is strong evidence for ram-pressure stripping of the HI caused by galaxy motion through the intracluster medium (ICM). There is at least one case in which a cluster- subcluster merger may have driven large bulk motions in the ICM, increasing the ram pressure by an order of magnitude. Finally, a number of galaxies have HI tails pointing away from the cluster center and appear to be falling into the cluster center for the first time. Clearly, in this nearest cluster of galaxies, we are seeing evolutionary processes that continue even to the present date, and are not just restricted to the distant early Universe.

Investigators: Aeree Chung (Columbia University), Hugh Crowl (Yale University), Jeffrey Kenney (Yale University), Jacqueline van Gorkom (Columbia University), and Bernd Vollmer (Strasbourg University).

Measuring the Size of the Black Hole at the Center of Our Galaxy

The VLBA has been used at its highest frequency of 86 GHz (λ = 3.5 mm) to image Sgr A*, the compact radio source at the center of our Galaxy. Observations at such a high frequency are necessary to reduce the interstellar scattering that smears images at lower frequencies. The intrinsic size of Sgr A* measured by the VLBA is only 1 AU, showing that the radio emission originates at less than 13 Schwarzschild radii from the event horizon of the black hole. When this size is combined with a lower limit on the mass, the resulting mass density of 6.5×1021 solar masses pc-3 provides the most stringent evidence to date that Sgr A* is a supermassive black hole.

Investigators: Z. Q. Shen, (Shanghai Observatory), K. Y. Lo (NRAO), M. -C. Liang (Caltech), P. T. P. Ho (ASIAA), J. -H. Zhao (CfA).

The Fastest-Spinning Neutron Star

Astronomers using the GBT have discovered a binary pulsar (PSR J1748−2446ad) in the globular cluster Terzan 5 that is rotating about its axis 716 times per second (P = 1.4 msec). The GBT now holds the record for the fastest-spinning pulsar known, breaking the nearly 25-year record held by the 642 Hz pulsar B1937+21. Studying maximally rotating neutron stars is important for a range of astrophysical problems that include constraining the equation-of-state of matter at supra-nuclear densities and estimating the importance of neutron stars as gravitational-wave sources.

Investigators: J. Hessels (McGill), S. Ransom (NRAO), Stairs (UBC), P. Freire (NAIC), V. Kaspi (McGill), F. Camillo (Columbia).

Program Plan FY 2007 B. FY 2006 Review 7

Detection of Biologically-Significant Molecules in the Interstellar Medium

In just over two years, an international research team has detected eight new complex, biologically significant molecules in the interstellar medium using the GBT. The discoveries are revealing the mechanisms by which complex molecules are formed in the ISM. Two mechanisms appear to account for these molecules: simple chemical reactions that add an atom to a molecular structure residing on the surface of a dust grain, and neutral-radical reactions that occur in the interstellar gas. The molecules acetamide (CH3CONH2), cyclopropenone (H2C3O), propenal (CH2CHCHO), propanal (CH3CH2CHO), and ketenimine (CH2CNH) were detected in the Sagittarius B2(N) cloud, and the molecules methyl- cyano-diacetylene (CH3C5N), methyl-triacetylene (CH3C6H), and cyanoallene (CH2CCHCN) were found in the Taurus Molecular Cloud (TMC-1). Acetamide is of particular interest since it contains a peptide bond in which an NH2 group is bound to a CO group. Such bonds provide the means for linking amino acids together to form proteins. The presence of such complex, biologically-significant interstellar species makes it increasingly plausible that interstellar chemistry played some role in the formation of the complex chemistry of the early Earth.

Investigators: J. Hollis (NASA-GSFC), P. Jewell and A. Remijan (NRAO), F. Lovas (NIST), L. Snyder (University of Illinois), H. Mollendal (University of Oslo, Norway), V. Ilyushin (Inst. of Radio Astronomy of the National Academy of Sciences of the Ukraine), I. Kleiner (University of Paris).

Figure B.2. (Left) New molecules detected with the GBT. (Right) The cycle of interstellar chemical evolution, from diffuse interstellar clouds, to dense clouds, to proto-solar accretion disks, to possible chemical seeding of planets by cometary collisions, to stellar mass loss from evolved stars, resulting in return of material to the interstellar medium and diffuse clouds (Credit: Saxton; NRAO/AUI/NSF).

Program Plan FY 2007 B. FY 2006 Review 8

VLBA Measures the Distance to the Perseus Spiral Arm

Using the VLBA, a team of researchers has measured a precise distance to the Milky Way’s Perseus spiral arm by determining the trigonomic parallax to several strong methanol masers in the W3OH star- forming region. Their direct measurement of 1.95 ± 0.04 kpc resolves a previous factor-of-two discrepancy in the kinematic distance to the Perseus spiral arm that arose because of anomalous motions in that part of the Perseus arm. The new result shows that the VLBA can measure distances out to 10 kpc with an accuracy 100 times better than that of the Hipparcos satellite and can lead the way to mapping the spiral structure and full kinematics of massive star-forming regions in the Milky Way.

Investigators: Y. Xu (Nanjing), M.J. Reid (CfA), X.W. Zheng (Nanjing), and K.M. Menten (MPIfR, Bonn).

A Gigantic Eruption from the Inner Disk of the Milky Way

Pidopryhora, Lockman, and Shields have used the GBT to discover a coherent structure that seems to be a huge superbubble extending more than 3 kpc from the Galactic plane. It has been detected in both Hα and HI, and a detailed HI map of it has been produced with the Green Bank Telescope. The total hydrogen mass within the outflow is ≈ 106 solar masses and its energy content is of order 1053 ergs. At the top of the structure there is a peculiar “plume” consisting of more than 104 solar masses of hydrogen, likely the cap of the superbubble which is now stalled in its expansion and undergoing instabilities.

Investigators: Y Pidopryhora and F. J. Lockman (NRAO), J. C. Shields (Ohio University).

Magnetic Collimation of Jets from an Evolved Star

VLBA polarization measurements of the AGB star W43A, which is rapidly undergoing evolution into a planetary nebula, have produced the first direct evidence for magnetic collimation of an astrophysical jet. The VLBA observations measured the polarization of 22 GHz emission from water masers at opposing tips of the jets. The magnetic field direction was shown to be almost perfectly perpendicular to the jet, consistent with a toroidal magnetic field. The magnetic pressure in these regions is seen to dominate the gas pressure by a factor of 2–200. This result supports recent theoretical models that use magnetically collimated jets to explain the shape of asymmetric planetary nebulae.

Investigators: W. Vlemmings and P. Diamond (Jodrell Bank), H. Imai (Kagoshima).

Program Plan FY 2007 B. FY 2006 Review 9

2. FY 2006 Technical Highlights

• Substantially reduced elevation dependence of GBT gain at 40 GHz through “out of focus” holography • Completed a 16-channel digital back-end from Caltech for the pseudo-correlation GBT continuum receiver for 26–40 GHz • Full release of the Astronomer’s Integrated Desktop (ASTRID) for the GBT • The Ka-band (26–40 GHz) and Q-band (40–50 GHz) GBT receivers were released as planned • Developed new amplifier designs covering 4–8, 4–12, and 12–18 GHz for the EVLA • Redesigned the 35–46 GHz amplifier developed originally for WMAP in order to achieve flat noise and gain over the 40–50 GHz EVLA frequency band • Developed a new GaAs MMIC power amplifier (PA), fabricated at BAE Systems, which meets the requirements for ALMA Bands 4, 8, and 9, with a longer lifetime than previous PAs • Continued a joint R&D project between the NRAO and UVa for a new 385–500 GHz beam-lead SIS mixer, supported mainly by an NSF grant to the UVa • Fabricated the first NbTiN trilayer structure (NbTiN/AlN/Nb) at the UVML • Designed and tested a superconducting 180-degree IF hybrid covering 4–12 GHz that is small enough to be mounted inside a balanced SIS mixer block • Designed and tested a scaled prototype of the holography feed for measuring ALMA antennas at 79 and 104 GHz. • Designed and tested a half-size prototype of the EVLA 2–4 GHz feed • Studied the beam pattern properties of a prime-focus array receiver for the GBT at 1.4 GHz and 2.5 GHz • Brought 20–70 MHz and 250–1000 MHz solar monitor systems into routine operation at Green Bank • A new VLA Proposal Submission Tool (common with GBT) made its debut • Four EVLA antennas are now functioning with four complete IFs and receivers for L, C, X, K, and Q-bands • The RFI-shielded room for the new EVLA correlator was completed in December 2005, and its shielding effectiveness was tested and verified • The formatter and 8-bit digitizer boards in the EVLA digital transmission system module was redesigned, fabricated and successfully tested • The three frequency converters that up- or down-convert the RF signals from the EVLA receivers to the 8–12 GHz IF of the EVLA were designed, prototyped, and placed into production • The new EVLA correlator chip design was released for production and 10 packaged chip prototypes were delivered to Penticton • All 10 VLBA antennas were equipped with Mark 5 data recorders, and the VLBA correlator has 11 Mark 5 playback units

ALMA FY 2006 technical highlights are described in the section on ALMA Construction.

Program Plan FY 2007 B. FY 2006 Review 10

C. Science Programs for FY 2007

Cosmology and the Early Universe

In this era of precision cosmology, observations have demonstrated that we live in a universe dominated by a mysterious dark energy. Dark energy (DE) accounts for 74% of the universe by mass but it is detectable only through its antigravity effects—accelerating the expansion of the universe and retarding the formation of large-scale structure. To constrain the DE equation of state, the most important complement to existing cosmic microwave background (MB) data is an accurate measurement of the Hubble constant H0. Astronomers from the NRAO, the Center for Astrophysics, and the MPIfR have begun a large program (the Megamaser Cosmology Project) to measure the current expansion rate of the universe H0 to 3% accuracy by purely geometrical means, providing a test of the Concordance Cosmology and improving our understanding of DE. The program will reach its goal by using the GBT to discover ten or more circumnuclear H2O masers in distant (D ~ 100 Mpc) Seyfert galaxies, determine their orbital velocities, and monitor their accelerations. The high-sensitivity array consisting of the VLBA, the GBT, and the Effelsberg 100 m telescope will image the circumnuclear disks, and distances to these disks will be calculated by the methods already used to measure the distance to the nearby galaxy NGC 4258.

Measurements of the temperature and polarization angular power spectrum of the CMB are increasingly limited by galactic and extragalactic foregrounds. Point sources contaminate small-scale (l > 2000) CMB anisotropies, while on larger scales there is a little-understood anomalous diffuse emission component in the microwave band. In 2007 the GBT will be used to measure 30 GHz flux densities for several thousand point sources in fields observed by other microwave background instruments, particularly the Cosmic Background Imager. The diffuse emission is correlated with dust but is not simply an extrapolation of known thermal or synchrotron spectra; it may be produced by spinning dust grains. The GBT will also be used to study the spectral and polarization properties of the anomalous dust-correlated emission.

The GBT will continue its searches of damped-Lyα systems for both neutral (HI) and molecular (OH, CO) absorption toward radio-loud quasars. Damped-Lyα systems have high column densities detected through line-of-sight absorption measurements toward distant quasars, and they are thought to contain most of the cold gas in the early universe. Thus radio observations of damped-Lyα systems with high spectral resolution probe the formation and evolution of galaxies when most of the baryons in the universe were in the gas phase. Such observations are also useful for detecting changes in the fundamental constants (the fine-structure constant and the electron-proton mass ratio) over the life of the universe.

Cosmic star formation in the redshift range z = 2–3 appears to be dominated by a population of dusty but luminous starburst galaxies, first identified on the basis of their sub-millimeter emission. The GBT is a powerful instrument for studying the molecular gas that powers these ultraluminous systems. Redshifted CO (1–0) emission, for example, remains the best method for determining the masses and dynamics of these systems. HCN emission traces cold dense gas and can be used to infer the physical properties within their star-forming regions. Initial indications are that these may be massive merging galaxies that trace the over-densities expected in hierarchical models of structure formation, and they may be the precursors of today’s giant elliptical galaxies found in the centers of galaxy clusters.

Program Plan FY 2007 C. Science Programs for FY 2007 11

Despite the enormous interest in dusty starburst galaxies, this population remains poorly studied owing to the small number of objects with accurately determined redshifts. In 2007 the GBT will be equipped with a new instrument, the Zspectrometer, that will be capable of doing “blind” redshift searches from 1.9 < z < 3.4. This facility instrument has been built in collaboration with the University of Maryland with funding from the National Science Foundation. The Zspectrometer is expected to more than double the number of starburst galaxies with accurate CO redshifts, masses, and line-widths, enabling detailed interferometric imaging with ALMA and the EVLA.

The GBT Ka-band receiver will be used to complete a blind survey for millimeter-wave absorption towards a radio-selected complete sample of 107 sources. Data for the first half of this project, a GBT Q- band survey of the same 107 sources, have already been obtained. The full survey will be sensitive to molecular absorbers in the redshift range 0.9 < z < 2.4. It will be the first entirely unbiased survey for molecular absorption and should result in a significant increase in the number of redshifted molecular absorbers. It will, for the first time, allow an estimate of the probability of finding a molecular absorber per unit redshift interval as well as the cosmological mass density of molecular gas in the above redshift range. Any detected systems will be followed up in HI λ = 21 cm and OH absorption for the dual purposes of studying physical and chemical conditions in the absorber and measuring changes in fundamental physical constants.

The GBT and the GMRT will be used to carry out deep searches for redshifted HI λ21 cm absorption in high-redshift damped-Lyα systems and in intermediate-redshift strong MgII absorbers. In parallel the WHT, VLT, and Gemini (optical) telescopes will be used to complete a survey for damped-Lyα absorption towards a radio-selected quasar sample, to yield new targets for follow-up λ = 21 cm absorption spectroscopy. This is a long-term program to elucidate the nature of damped absorbers, the precursors of present-day galaxies, and thus to probe galaxy evolution. The observations will also yield a sample of high-redshift λ = 21 cm absorbers which will be followed up with high-resolution Keck-HIRES or VLT-UVES spectroscopy to measure changes in the fine-structure constant and the electron-proton mass ratio.

The GBT will be used to obtain sensitive spectra of the redshifted CCH 1−0 lines from the z ~ 0.885 gravitational lens towards PKS 1830−210 in an attempt to use these lines to probe fundamental-constant evolution over cosmological time scales. In parallel, the molecular structure of CCH will be analyzed to obtain the precise dependences of the different transition frequencies on the fine-structure constant and on the electron-proton mass ratio.

The VLA will be used to make a deep observation of the Mitchell-Condon field at about 320 MHz with a resolution of ~ 5 arcsec. Spectral indices will be determined by comparison with 1.4 GHz images. Optical multi-band images of the entire field have been obtained with the CFHT telescope. The aim is to detect unusual objects for further study.

Work will continue on the deep SWIRE field 1046+59. The λ = 90 cm VLA survey of the field, which is the deepest ever made at that wavelength, will be completed. Together with the λ = 20 cm data and a deep GMRT survey at λ = 50 cm, these data will be used to define the low-frequency radio spectra of the microJy source population. A confusion-limited Spitzer survey will also be completed late in this period and will be used, among other things, to constrain the radio/FIR correlation at high redshift. Further imaging in the near infrared with the CFHT and in the radio with the GMRT will occur during this period. These data will be used to improve the photometric redshifts and our understanding of the evolving SEDs of distant galaxies in this field.

Program Plan FY 2007 C. Science Programs for FY 2007 12

A multi-wavelength follow-up program will continue on the COSMOS HST Legacy field using the 1/4 square degree deep survey at λ = 1.1 mm made with Bolocam and the deeper 1/8 square degree survey at λ = 1.2 mm made with MAMBO (completed in 2004 / 2005). Combined, these surveys have produced a candidate list of ~50 ultraluminous high-redshift dust-enshrouded starbursts and AGN (“submillimeter galaxies”). A recent deeper VLA λ = 21 cm image of the field as well as Cycle 2 Spitzer IRAC and Cycle 3 MIPS observations will be included in the ongoing analysis to provide improved information on the luminosities, redshift distribution, and SEDs of these galaxies. New observations, including λ = 350 µm photometry (CSO/SHARC-2) and optical spectroscopy (VLT-VIMOS and Keck-DEIMOS) will be undertaken, and CO spectroscopy using the GBT and a new diffraction-grating spectrometer at the CSO (see Instrumentation below) will be proposed.

Radio Galaxies, Quasars, and Active Galactic Nuclei

In late 2007 NASA will launch its long-awaited Gamma Ray Large Area Space Telescope (GLAST). VLBI imaging, which resolves the AGN jets associated with the gamma-ray radiation, is critical for maximizing the scientific return from GLAST. In preparation for GLAST, the VLBA Imaging and Polarimetry Survey (VIPS) got underway in 2006 and will be finished by 2007. The goal of VIPS is to make VLBA observations of a well-defined statistically complete sample of compact radio sources that are likely to be detected by GLAST following its launch in late 2007. Many intriguing new sources have already been discovered, including several candidate supermassive binary black-hole systems. Such systems are important for estimating black-hole coalescence rates for current and future generation of gravitational wave detectors.

In recent years the studies of relativistic large-scale (kiloparsec) jets in AGN are undergoing a renaissance thanks to the availability of high-resolution multi-wavelength data from the Spitzer Space Telescope, Chandra X-ray Observatory, Hubble Space Telescope, and Very Large Array. Detailed images from these observatories are being obtained and analyzed with a goal of using the AGN emission properties to determine the collimation and the acceleration of the relativistic flows in quasar and AGN jets. Of particular interest are the highest redshift (z ~ 4) relativistic jets being studied with the VLA, VLBA, and Chandra. Multi-frequency imaging of these kiloparsec-scale jets will help test emission models and constrain fundamental physical parameters (magnetic field strengths, electron energy distributions) of these actively accreting supermassive black-hole systems in the young Universe.

High-quality VLA imaging and polarimetry of the radio jets in several FRI radio galaxies will be combined with Chandra and XMM imaging to elucidate the dynamical parameters of the jet outflows as functions of distance from the AGN, to explore the jet-gas interactions that control kiloparsec-scale jet collimation and deceleration in these AGN outflows, and to identify the sites (and hence constrain the mechanisms) of relativistic-particle acceleration within them. Multi-frequency polarimetry of FRI radio galaxies and X-ray data on their hot gaseous environs will be used to examine the spatial statistics of the magnetoionic media around the galaxies and to derive the spectrum of the magnetic field fluctuations in hot gas associated with the surrounding groups.

VLA and Chandra data will be combined to extend the radio/X-ray correlation (observed in stellar-mass black holes) to low-mass active galactic nuclei in order to probe similar physics over six to eight orders- of-magnitude in mass.

The most extensive sets of measurements of molecular line emission in external galaxies are based on -3 CO and HCN. Since CO and HCN are good tracers of dense gas (n(H2 > 104 cm ) but do not provide specific information about the individual physical conditions in these regions, a molecule that allows for a simpler interpretation of its emission is required. Formaldehyde (H2CO) has proven to be a reliable

Program Plan FY 2007 C. Science Programs for FY 2007 13

density and kinetic-temperature probe in Galactic molecular clouds. Exploiting the unique density selectivity of the K-doublet transitions of H2CO, the GBT will be used to measure the dense-gas structure and spatial density in a sample of nearby and luminous galaxies.

Nearby Galaxies

The nature of the ultra-luminous X-ray sources (ULXs), first studied in detail by the Chandra satellite, remains a hotly debated topic. The two most popular explanations are relativistic beaming from stellar- mass sources, which would imply a huge number of sources, and isotropic emission from intermediate- mass black holes, which would require some previously unsuspected mechanism to make such beasts. VLA studies should help constrain the physical nature of these intriguing objects. Preliminary radio observations have found no clear point-like counterparts but sometimes show extended (hundreds of parsecs) emission near the ULXs. Although not conclusive, the latter result tends to support the isotropic model and provides evidence for an astrophysically important population intermediate between stellar- mass black holes and the supermassive black holes that power AGN.

The VLA will also be used to search for radio emission from G1, a globular cluster in the nearby Andromeda galaxy whose dynamics indicate that it may contain an intermediate-mass black hole of about 20,000 solar masses. If it does, this may be the nearest version of the intermediate-mass black holes found in a number of nearby low-luminosity active and inactive galaxies. The possible existence of intermediate-mass black holes at the centers of globular clusters is of interest because of their relation to ULX sources in star-forming galaxies and the global relation between galaxy-halo and black-hole masses. An important discriminator between a collection of stellar-mass black holes in binary systems and a single massive black hole is the relation between X-ray and radio luminosity. The VLA observations will be used to compare the limits/detections of X-ray and radio emission to those of stellar- mass and intermediate-mass black holes, and thereby test the inference that G1 contains a 20,000 solar mass black hole.

The VLA will be used to measure the kinematics of spiral galaxies beyond their optical disks using neutral hydrogen. The kinematics will be combined with Hα imaging to produce multi-scale multi- wavelength velocity fields of the highest quality for a large sample of nearby spirals. These systems will be used to study the impact of baryons on the dynamics of disk galaxies in an effort to understand the nature of long-standing discrepancies between Cold Dark Matter Paradigm predictions and observations on galaxy scales.

The VLA will also be used to study the kinematics of hydrogen-deficient galaxies in the periphery of the Virgo cluster by probing their HI emission with unprecedented resolution and sensitivity. The observations will elucidate what physical processes play a role in the HI deficiency of galaxies inhabiting the suburbs of clusters, thus providing further insight into the connection between the properties of galaxies and their environments.

Molecular Clouds, Star Formation, and Galactic Structure

In the past several years the GBT has proven itself to be the premier instrument in the search for biologically significant molecules in interstellar and circumstellar environments. However, in addition to adding to the list of new molecular species, the GBT and the VLA are beginning to answer longstanding questions about the formation of molecules in the interstellar medium (ISM). For the first time, high- resolution and high-sensitivity instruments are available to accurately measure and map the locations of molecular species in the ISM with respect to the infrared or millimeter-wave continuum sources primarily heated by thermal processes or shocked regions that are traced primarily by molecular maser emission.

Program Plan FY 2007 C. Science Programs for FY 2007 14

Observations of the abundances and locations of molecular species will determine whether each molecular species is formed via gas-phase or grain-surface chemistry and how the species was liberated into the gas phase.

Over the next year the GBT will investigate the interstellar chemistry of the low-mass-star-forming region IRAS 16293−2422 by searching for complex molecular species including formic acid (HCOOH), methyl formate (CH3OCHO), methyl cyanide (CH3CN), dimethyl ether (CH3OCH3), and ethyl cyanide (C2H5CN) at frequencies near 43 GHz (λ = 7 mm). In addition the GBT will continue the investigation of the best- known source for large molecules in the Galaxy, the high-mass-star-forming region Sgr B2(N), by searching for interstellar hydrogen peroxide (H2O2).

The VLBA will be used in 2007 to measure the absolute positions of water masers and continuum sources in the nearby low-mass-star-forming regions Rho Ophiuchus and Taurus. Repeated measurements of absolute positions disentangle the parallax, the overall cloud motion, and the peculiar motions. The parallax measurement will allow an estimate of the distance to these low-mass-star-forming regions with an accuracy of about 0.5%. Not only will a precise distance lead to the best determination of the luminosities, jet velocities, outflow momenta and many other physical quantities in this star-forming region, but it will also give a unique opportunity to look at the three-dimensional structure of the cloud and its relationship to the stars in the Upper Scorpius subgroup. The VLBA is the only instrument in the world that has the capability to make this kind of accurate astrometric measurement.

The GBT will be used to image protostellar cores at λ = 7 mm and λ = 9 mm. High-spatial-resolution measurements of their centimeter-wavelength dust continuum emission are key to their evolutionary characterizations, as long-wavelength dust continuum emission has the highest probability of being optically thin and therefore a direct measure of the mass in a protostellar core. The GBT is the most sensitive telescope at long millimeter wavelengths. When combined with dust-continuum observations at submillimeter wavelengths, millimeter-wavelength continuum observations provide a substantial lever arm to constrain dust opacities.

The Endpoints of Stellar Evolution

Catastrophic supernova explosions terminate the lives of massive stars, release tremendous amounts of energy, and herald the births of black holes and neutron stars. These compact stellar remnants present astronomers with physical laboratories that probe the extremes of matter, gravity, and magnetic fields found anywhere in the universe. A small fraction of these events are accompanied by the mysterious gamma-ray bursts, rendering them visible throughout the Universe.

The VLA will continue to make follow-up searches for long-lived afterglows of gamma-ray bursts identified by the Swift satellite. Joint observations at X-ray, optical, and radio wavelengths can be used to constrain important physical parameters of these relativistic explosions. In 2007 the research will focus on the nearest gamma-ray events (see below) and on the most distant (z > 5).

The VLA will be used to study new extragalactic supernovae in the local universe. Carefully modeled light curves also yield information on the circumstellar environment of the pre-supernova star, as well as the explosion energy and the velocity of any relativistic ejecta. Such studies will also be used to explore the link between gamma-ray bursts and core-collapse supernovae (SNe Ib/c).

Program Plan FY 2007 C. Science Programs for FY 2007 15

891 will probe the physical character of the unique source near the center of the expanding shell, which may be the first direct signature of a compact remnant associated with a recent supernova.

It is estimated that only about one percent of the total population of the active pulsars have been detected since their discovery in the late 1960s. Today, the excellent pulsar search capabilities of the GBT at 350 MHz will allow us to continue this census with the most sensitive pulsar survey ever of the northern galactic plane. The discovery of even a single new “well timed” northern millisecond pulsar could be essential to the success of pulsar timing arrays for discovering extremely low-frequency gravitational waves.

Targeted pulsar surveys benefit from the low-interference and high-bandwidth capabilities of the GBT receivers and Spigot backend. In the past several years the GBT has nearly doubled the number of millisecond pulsars found in globular clusters. This bonanza of 56 new millisecond pulsars includes the most rapidly rotating neutron star known. Work continues on timing these new systems, measuring neutron-star masses, providing constraints on the equation of state of matter at supra-nuclear density, studying globular-cluster mass distributions, and testing gravitational theories.

In 2007 targeted high-frequency searches will be made of the Galactic Center region. The expectations are that many hundreds of pulsars are in orbiting the central black hole SgrA*. The GBT may be able to find between two and 30 pulsars, assuming a 20% beaming fraction and including uncertainties in the distribution of pulsar spectral indices and in the total number of pulsars in this region. The discovery of an orbiting population would be a boon to experiments that test predictions of general relativity in the strong-field regime.

Magnetars represent another extreme in compact objects, with magnetic fields of order 1015 G. They reveal themselves through repeatable bursts of high-energy emission (the soft-gamma-ray repeaters) or slow X-ray pulsations (the anomalous X-ray pulsars). We presently do not understand the relationship between magnetars and the normal rotation-powered pulsars with magnetic fields of “only” 1012 G. The recent discovery of radio pulsations from the transient anomalous X-ray pulsar XTE J1810−197 has presented astronomers with an unexpected gift to explore this connection. In 2007 the GBT and VLA will observe XTE J1810−197 and any newly active magnetars to study the magnetospheres and rotational behaviors of these extraordinary systems.

The connection between accretion and outflow in black-hole and neutron-star X-ray binaries will remain an active research area for the VLA and VLBA in 2007. The kinetic energy carried way from the vicinities of accreting black holes likely represents the bulk of the feedback of energy and mass lost from these systems into the surrounding medium. While the X-rays primarily probe the accretion disk and halo, radio observations provide the only direct, unambiguous indication of a relativistic jet. Thus astronomers must combine data from the VLA and the VLBA with X-ray (RXTE, Swift, Chandra, XMM), optical/infrared and far-infrared (Spitzer) observations to explore this connection further. Studies of galactic stellar-mass black holes may offer us some insight into the evolution of supermassive black holes that are ubiquitous in the universe.

Solar System

Now that we are deep in the minimum of the 11-year sunspot cycle, solar research has turned to the study of the quiet Sun. In one such study, the VLA will observe the large-scale coronal loops that join active regions across the solar equator. The formation of these structures may be related to large-scale rearrangement of magnetic fields in the corona. The subsequent explosive energy release may play a role in coronal mass ejections and serve as an important coronal heating source. Radio observations trace the

Program Plan FY 2007 C. Science Programs for FY 2007 16

energetic particles released in these reconnection events, and, together with extreme UV and soft X-ray observations from the SOHO and RHESSI space observatories, they can build a complete picture of the formation and evolution of these trans-equatorial loops.

Understanding the interior properties of the planet Mercury has important implications for the thermal evolution and magnetic-field generation of the terrestrial planets. This is one of the key scientific objectives of the MESSENGER mission due to arrive at Mercury in 2011. Such measurements are possible now thanks to a novel observing technique developed in 2004 using the GBT and the Goldstone antenna. The bistatic-radar speckle-displacement method yields precise measurements of the spin rate of Mercury, leading to the detection of forced librations, a signature that can only be explained if the planet has a molten core. In 2007 the GBT will continue to measure the spin-rate deviations of Mercury in an effort to confirm a long-period free libration indicative of core-mantle interactions.

The constant bombardment of the Moon’s surface has created a mixed layer of pulverized dust and rock fragments called the regolith. Variations in the depth and rock-size distribution of the regolith in the lunar highlands and in the ancient basin floors contain detailed information about the cratering history of the moon. The GBT will be used with the Arecibo telescope to make high-resolution (20 m/pixel) radar images of the Moon at wavelengths λ = 70 cm and λ = 13 cm that probe the regolith to depths in the range tens of meters to kilometers in and around several craters.

The Cassini spacecraft, now in the Saturn system, has revealed the unusual properties of the moon Enceladus whose albedo exceeds 0.9. The south-polar region is particularly intriguing, with so-called “tiger stripes” 70 K warmer than the equatorial regions and producing significant amounts of CO2 and H2O. Observations of Enceladus as it occults the radio source 3C 228 will permit the detection of OH around that moon, constraining the large-scale distribution of the gas in the system and the production rate of water from the body. In a separate experiment the VLBA will also be used to track the Cassini spacecraft itself. From VLBA runs over the next two years we expect to determine the position of Saturn with respect to the quasar background to 0.1 milliarcsec accuracy. At present the position of Saturn is uncertain by 1.0 milliarcsec.

In 2007 the north pole of Uranus will emerge into sunlight for the first time in 42 years. Observations during the next few years will be especially timely because the planet is nearly at equinox. Radio observations of Uranus provide important information on the deep atmosphere, including temperatures and abundances (notably of ammonia, the major variable contributor to opacity at longer radio wavelengths). Observations of the deep atmosphere are critical for deducing the dynamics between the deep and shallow atmospheres. The ongoing program of VLA observations of the planet will continue, enabling comparison of the physical properties of Uranus at its northern and southern latitudes.

Program Plan FY 2007 C. Science Programs for FY 2007 17

D. ALMA Construction

Accomplishments in FY 2006

FY 2006 was dominated by the rebaselining exercise and the subsequent reviews. The ALMA Cost Review of the rebaselined project was held in Garmisch-Partenkirchen on 13–15 October 2005. This was an international review chaired by Steve Beckwith and co-chaired by Thijs de Graauw. In the final days before the Cost Review it became clear that the project would procure antennas from two different vendors and that a Delta Review would be required in the early New Year to examine the cost implications of this. In addition, the NSF requested a North American Cost/Management Review to review the NSF component of the ALMA budget and on a similar timescale to the Delta Review.

Shortly after the ALMA Cost Review, a high-level delegation from the NSF/NRAO/AUI visited Taiwan to discuss the prospect of Taiwan joining the North American ALMA partnership.

At its November Board meeting the ALMA Board approved a number of the budget change proposals (BCPs) that had been proposed in Garmisch. Subsequently these were entered into the project budget.

An exercise led by the JAO was initiated in late November to review the Value Balance on the ALMA project, a prerequisite to determining the split of the overall ALMA budget between North America and ESO.

In the early New Year both the Delta Cost Review and the North American ALMA Cost/Management Review were held. The Delta Review panel was a subset of the original Garmisch Review panel and concluded that the project had both made good progress and correctly assimilated the costs of having two antenna vendors.

The North American ALMA Cost/Management Review was chaired by Don Hartill from Cornell and was an independent review of both the North American costs and the North American Management of the Project. This review was a success and concluded that the costs were both understood and under control; it further concluded that the North American (NA) ALMA Management was capable of delivering its part of the project.

NSF called for a fourth review in April, this time of the contingency associated with ALMA, and asked us to undertake an exercise to bring the contingency up to 25% of the uncommitted budget. This review concluded that we had come close to achieving the 25% target through parametric cuts but that we should increase the contingency somewhat by adding additional cash as well. They also endorsed carrying an additional contingency to deal with the potential for Japan to contribute 20% to the site cost increase.

The NSB approved the new ALMA baseline at their May 2006 meeting.

In early 2006 agreement was reached between NSF and ESO that AUI would hire the local staff in Chile. Since then work has largely concluded to allow AUI to hire the ALMA Local Staff in Chile and the first staff member has been hired. The AUI Implementation Plan was approved by ALMA Board on March 24. The amendment to the ALMA Agreement designating AUI as the employer of Local Staff for the Bilateral Project was approved by ESO Council on June 6, signed by the ESO Director General June 14. NSF approved in early July and then the AUI/ESO Management Agreement was signed. This, inter alia, designates the NRAO Director as responsible for Local Staff matters; formally establishes the “Director’s

Program Plan FY 2007 D. ALMA Construction 18

Council” consisting of NRAO Director, ESO Director General and ALMA Director, and enables sharing of procurement information between AUI and ESO.

During FY 2006 the Site IPT made very significant progress with the construction of the Array Operations Site (AOS) Technical Building (TB) foundation, superstructure, and envelope all completed. The contract for the AOS TB completion, which includes all architectural interior furnishings, was signed. The procurement of the NRAO-furnished equipment for the AOS TB (all technical-equipment installation, such as HVAC, fire suppression, control systems, and oxygen enrichment) is well underway. In addition, the NRAO completed the Contractors’ Camp at the Operations Support Facility (OSF) level, at an altitude of approximately 9,600 ft. This work was finished in early November 2005 and involved construction and outfitting of the facilities to be used for housing the contractors who will populate the site over the next several years of construction. Finally the preparation of the Vertex lay-down area at the OSF for antenna assembly was completed, together with the necessary antenna foundations and underground utilities.

The Antenna IPT (Integrated Product Team) completed the Vertex Antenna Preliminary Pre-Production Design Review in February and the Pre-Production Design Review (scheduled for September 2006). As part of this process Vertex completed the antenna design changes needed for production, all antenna manufacturing drawings, all antenna finite-element analyses, the antenna metrology-system investigation and redesign, and procurement of all antenna long-lead items. The assembly of the pedestal and yoke- arm structure is scheduled to commence in September 2006 at Vertex’s dedicated ALMA Antenna integration facility in Kilgore, Texas. In addition to the antenna, ancillary ALMA antenna-equipment activities completed were Production Nutator technical specification and Statement of Work, competitive bidding process and evaluation of proposals, Production Optical Pointing Telescope technical specification completed, and early collaborative work with commercial optical-telescope vendors ongoing. Finally, two key positions of Quality Assurance engineer and Antenna engineer were filled.

The Front-End IPT (FE IPT) made steady progress toward delivery of the first Front End. All cold- cartridge groups have built and tested their first receivers, and the first deliveries to the North American Front End Integration Center (NA FEIC) took place. The sensitivity of these cold cartridges substantially exceeds the performance of any other mm-wave receivers ever built. The test facilities at the NA FEIC were essentially completed, and assembly and initial test of the first FE began in July 2006. Agreement was reached on the design of the amplitude-calibration device and serious design work began. Many FE subassemblies and components are now in full production mode. Agreements on FE local-oscillator (LO) requirements and configurations were reached with ALMA-J (ALMA Japan) in order not to delay Band 4 and Band 8 work.

The Back-End IPT (BE IPT) completed delivery of prototype modules to Prototype System Integration and resolved successfully most of the deficiencies noted so far in system testing. Successful cross- correlation tests were performed from front end to correlator using the BE digital data system and LO references. The BE IPT also delivered inter alia: sixteen Digital Transmission System (DTS) deformatter/receiver boards for testing on the correlator first quadrant and BE deliverables to the FE IPT for holography testing of antennas in Chile. Construction of modules and performance of environmental and other tests are currently on schedule for delivery of pre-production racks for the first antenna in early CY 2007, delivery of a limited Central LO (125 MHz and TE references only) to the OSF for single- antenna testing in October 2006, and delivery of Central LO equipment to the AOS in CY 2008.

The Correlator IPT substantially completed the first quadrant and began construction of the second quadrant. A full complement of optical receiver boards (DRX) from the Back End IPT and two new low- power Tunable Filter Bank (TFB) cards from U. Bordeaux permitted verification of all card slots,

Program Plan FY 2007 D. ALMA Construction 19

interfaces, and cables in the first quadrant. A plan was implemented for volume production of the TFB cards. All printed-circuit boards (except TFB) have been completed and almost all have been tested. Upgrades of the two-antenna prototype correlator firmware were done to support Prototype System Integration.

The Computing IPT performed the first end-to-end test of the whole ALMA computing system with a real observing mode (optical pointing, needed first for antenna acceptance) and with real hardware at the Antenna Test Facility (ATF). Good progress has been made on the off-line processing system with the creation of an execution framework for CASA to enable the use of the popular Python scripting interface rather than the in-house Glish system. Other achievements include the implementation of TFB support in the correlator software to enable hardware testing, finishing the definition of the raw data ALMA Science Data Model (ASDM), and implementation of a manual scheduling mode in the dynamic-scheduling subsystem to support initial observatory operations. In addition the IPT performed six external user tests.

The main Systems Engineering and Integration (SE&I) effort at the NRAO remains the Prototype System Integration (PSI) taking place at the Array Operations Center in Socorro, NM. In December 2005 the complete set of racks and modules for a two-antenna interferometer was available to PSI for system-level testing. The first task was to achieve full system connectivity among all hardware with reliable computer monitor and control. Numerous timing problems were discovered as well as phase stability and phase- lock problems in the LO system. While the discovery and resolution of problems can be time consuming, it demonstrates that PSI is doing what it should be—finding problems before we move to Chile. Some hardware changes were initiated. In July 2006 full connectivity was achieved with a 100 GHz signal injected into the Front-End Simulator and a cross-correlation spectrum displayed at the correlator output. The main task now is to demonstrate in the lab the software control of phase switching, phase tracking, delay tracking, and automatic level control needed for astronomical interferometry. Then PSI will be ready to move out to the prototype antennas at the ATF; this is expected by the start of FY 2007.

During FY 2006 the Science IPT led studies of ALMA's ability to address level-one science goals as it builds to its final complement of antennas. An array configuration was developed that can provide excellent imaging with an antenna complement ranging from 50 to 64 elements; fewer stations are a cost- saving feature of this array design. During the course of the year, antenna contracts were placed; the science IPT addressed whether ALMA science goals could be met with an array of differing antenna designs. As long as ALMA antennas meet their specifications, it is clear that an ALMA constituted of antennas of different designs is fully capable of delivering top-level science as planned. The ALMA Calibration Plan was refined to encompass particular examples for the various sorts of calibration. These examples were reviewed and commissioning of the various calibration sorts was examined with a focus on what might be done during PSI and what must await Assembly, Integration, and Verification (AIV). The Front End IPT installed the prototype water-vapor radiometers on elements of the Smithsonian Submillimeter Array on Mauna Kea; Science IPT members began evaluating results. At 230 GHz on 200 m baselines, preliminary results show excellent promise; a meeting is planned in October to evaluate the results. The Science IPT led a System Requirements Review in order to detail the flowdown of science requirements through system requirements to an assessment of detailed system performance. The Science Specifications and Requirements document was approved by the ALMA Board. ALMA was represented at a number of regional and international meetings through the year. In North America, one particular focus was on a meeting “From ZMachines to ALMA” held in Charlottesville in early January 2006, just after the Town Meeting at the AAS in Washington.

Program Plan FY 2007 D. ALMA Construction 20

NA ALMA Plans for FY 2007

Overview of North American Objectives

The NA ALMA project will engage in several top-level tasks in FY 2007 that have major import for the future of ALMA construction and operations. The most significant event of 2007 will be the acceptance of the first Antenna at the OSF. The Management IPT will coordinate the response to the Japanese RFQ (request for quote) and complete negotiations with Taiwan over the details of their deliverables as part of their involvement in ALMA. The Site IPT will oversee completion of the outfitting of the AOS Technical Building, and it will place contracts for the high-site roads and power distribution. The Antenna IPT will support the delivery of the first antenna in Chile and will place contracts for the nutators and the optical pointing telescopes. The Front End IPT will complete the remaining design of all front- end work and deliver the first three front-ends for ATF testing and installation in Chile. The Back End IPT will deliver the first complete sets of electronic modules for Chile and place the contracts for the main photonic LO components. The Correlator IPT will complete installation of the first quadrant of the correlator at the AOS TB and will complete integration of the second quadrant in Charlottesville. The Systems Engineering and Integration IPT and Science IPT will be engaged in the prototype antenna integration at the ATF. First fringes will be seen at the ATF during FY 2007.

Project Management (Management IPT)

Joint ALMA Office (JAO)

The JAO was created by the ALMA Board as the central management structure for the ALMA construction phase. The three key JAO positions currently filled are:

ALMA Director Massimo Tarenghi ALMA Project Manager Anthony Beasley ALMA Project Engineer Rick Murowinski

Recruitment for an ALMA Project Scientist is underway. On a rotating basis, the three Regional Project Scientists are performing the duties of the JAO Project Scientist for 4-month periods.

Project Milestones

The (hundreds of) detailed ALMA project milestones from the Integrated Project Schedule (IPS) are available on request. Key milestones have been pulled out and are distributed throughout this program plan as key objectives. Where these objectives refer to quarters, they are calendar year, not fiscal year.

Project Management Control System

The fully functional PMCS with earned-value reporting is now in place with clean-up work in the final stages to ensure that the reporting is accurate and complete.

Japan Partnership

An agreement was signed in July 2006 by the NSF, ESO, and the National Institutes of Natural Sciences/National Astronomical Observatory of Japan (NINS/NAOJ) to bring the Japanese formally into the ALMA project. This provides for the Japanese contribution to the project of four additional 12-m

Program Plan FY 2007 D. ALMA Construction 21

antennas, twelve 7-m antennas in the ALMA Compact Array (ACA), a separate ACA correlator, and receiver bands 4, 8, and, subject to successful technical development, band 10.

The details of the agreements among the two executives and the NINS/NAOJ are currently being negotiated. While the JAO is coordinating the Japanese entry into the project, each executive is responsible for its own agreement with the Japanese; the bilateral management is not involved directly with the Executives’ negotiations. No impact on or delay to the bilateral project is allowable because of the executive/Japanese agreements. The AUI/NRAO and NINS/NAOJ will finalize their agreement during FY 2007, within the broader context of the Japanese relationship coordinated by the JAO.

Taiwan Partnership

It is anticipated that the American Institute in Taiwan (AIT)-Taipai Economic and Cultural Representative Office (TECRO) agreement will be signed by the end of calendar year 2006. The Management IPT will support this process as needed. Meanwhile at the IPT level detailed discussions are underway to identify areas where Taiwanese industry can make an in-kind contribution. This work will be underpinned by IPT level MoUs and detailed Statements of Work. Through 2007 efforts will continue to identify and transfer appropriate work to Taiwan. When a piece of work is transferred to Taiwan, two PMCS change requests will be initiated. The first will remove the budget for that item from the NA WBS (work breakdown structure); the second will add a new budget item to over the costs of NA IPT work to oversee that work transferred to Taiwan.

Santiago, Chile Office

Doing business in Chile requires that the NRAO/AUI maintain an office in Chile separate from the JAO to interface between the NRAO/AUI and the Chilean government and scientific community, and to provide NRAO/AUI legal standing in Chile.

Representation issues for the Chile office in 2007 will include monitoring the land-access requirements including the Land Corporation, environmental commitments, relations with authorities including Region II, accreditation of NA Expatriates, administration of the ALMA-CONICYT science Fund, and relations with the local science communities. An important task for 2007 will be the development and implementation of a plan to collocate the ALMA Central Office and the NA Executive offices in a permanent location in Santiago.

Business activities on behalf of the NA component of ALMA in Chile in 2007 will include the Completion Package for the AOS Technical building, including development and monitoring of the associated contracts and procurement activities; contracts and biddings for the design and building of the road-construction package for the AOS; an extension of the ALMA Camp; and the contract and bidding for the design of the power and fiber network at the AOS. In addition the Chile Office will continue its administrative activities at the ALMA Camp with oversight for a number of support contracts, including support for Vertex activities. The Chile office, now that Local Labor is legally under the NRAO, will assume responsibilities for oversight of aspects of ALMA HR (human resources) activities including payroll.

Program Plan FY 2007 D. ALMA Construction 22

Table D.1. Project Management Control System Milestones Item Delivery Date Complete the clean up of the PMCS data 10/2006 Finalize the agreement between AUI and NINS/NAOJ Q4/2006 Support the procurement activities of the Site IPT in an efficient and 10/2006 timely manner Develop and implement for a plan to co-locate the ALMA Central Office and the NA Executive offices in a permanent location in 06/2007 Santiago

Site IPT

The Array Operations Site (AOS) is at an elevation of 16,500 ft above sea level. The NRAO is responsible for the design and construction of the AOS including the TB (Technical Building) and the infrastructure of the AOS (roads, power distribution and communications). The antenna foundations at the AOS were transferred to ESO as part of the rebaselining process.

Completion of the AOS TB is scheduled for April 2007. The procurement of the NRAO-furnished equipment for the AOS TB (all technical-equipment installation, such as HVAC, fire suppression, control systems, and oxygen enrichment) is well underway and will be completed in FY 2007.

Figure D.1. A View of the AOS Technical Building site at Chajnantor.

Program Plan FY 2007 D. ALMA Construction 23

Two calls for proposals will be issued for the Power & Fiber Optic distribution. The first is for the design work and the second is for the subsequent construction, which will continue in FY 2008 and beyond.

Expansion of the ALMA Camp will continue with the second stage of enlargement, to house up to 60 members of the ALMA IPT teams, being completed. A similar expansion of the Contractor’s Camp, to house up to 300 people, will also be undertaken.

A call for proposals for an AOS transporter-shed design and construction will be initiated with a view to construction starting in FY 2008.

Figure D.2. A view of the first ALMA antenna foundation (Vertex area).

Table D.2. Site IPT Milestones Item Delivery Date

Complete construction of the AOS Technical Building 04/2007

Complete enlarging the ALMA Camp 03/2007

Complete enlarging the Contractor’s Camp 03/2007

Call for bid for the power and fiber optic distribution design 11/2006 Call for bid during mid 2007 for the construction of power and FY 2008 fiber-optics distribution

Program Plan FY 2007 D. ALMA Construction 24

Antenna IPT

The primary Antenna IPT goal for the coming year is acceptance of the first Vertex production antenna at the OSF in April 2007; indeed this will represent one of the most significant milestones in ALMA’s history. In support of this, Vertex must complete their Site Erection Facility at the OSF.

Figure D.3. FE Model for the Vertex-designed ALMA production antenna.

Figure D.4. Construction of the Vertex Antenna Integration Facility in Kilgore, TX.

Program Plan FY 2007 D. ALMA Construction 25

Beyond the main production-antenna contract, the Antenna IPT is also responsible for the provision of nutators to allow the ACA to measure total power and optical pointing telescopes for the Bilateral Array. Both of these will go under contract in FY 2007.

Activities beyond FY 2007 revolve around continued delivery to ALMA of antennas at an approximate rate of one antenna every two months. This will require attention to all aspects of the supply and manufacturing chain as well as developing mitigation strategies to deal with unexpected but inevitable disruptions.

Completing acceptance and delivery of the remaining ancillary devices, nutators, and OPTs will also occur soon after FY 2007.

Figure D.5. First CFRP BUS segment.

Figure D.6. Fabrication of Invar cone at VertexRSI in Mexia, Texas.

Program Plan FY 2007 D. ALMA Construction 26

One crucial component of this entire process is the reliable operation of the antenna transporter vehicle that ESO will provide. At any point in time there will be five antennas in various stages of production and testing at the OSF, so the ability to move antennas from and within the Vertex assembly area will be critical to maintaining the flow of the production line.

Table D.3. Antenna IPT Milestones Item Delivery Date

Accept the first Vertex Antenna at the OSF 04/2007

Place the contract for the ALMA nutators 11/2006

Place the contract for the ALMA Optical Pointing Telescopes 01/2007

Front End IPT

The front end for each ALMA antenna will be contained in a single cryogenic dewar designed to accommodate ten receiver cartridges, one per wavelength band. Initially only four cartridges will be built, for the bands 3, 6, 7, and 9 at λ = 3 mm, 1 mm, 0.85 mm, and 0.45 mm; cartridges for bands 4 and 8 will be supplied by ALMA-J beginning with FE #3 or #4. The λ = 3 mm cartridge is built in Canada and the λ = 1 mm cartridge is built at the NRAO Technology Center (NTC) in Charlottesville. The λ = 0.85 mm and 0.45 mm cartridges, cryostats, calibration devices, and water-vapor radiometers are the responsibility of the Europeans. The NRAO supplies all local-oscillator assemblies, chassis, and supporting electronics.

In FY 2007 the NA ALMA Front End IPT (FE IPT) will complete the Front End Test and Measurement System (FETMS) at the NRAO Technology Center (NTC). The FE IPT will complete and test the first three front ends at the NTC and deliver them to the ATF and/or to the OSF, as required by the antenna and PSI schedules. The designs and procedures needed for handling front ends in Chile will be completed, including the service-vehicle design and interfaces to the Antenna and Site IPTs. The holography transmitter and receiver will be delivered to the ATF for operational testing and then sent to the OSF.

Table D.4. Front End IPT Milestones Item Delivery Date

Make the NA Front End Integration Center operational 10/2006

Complete and deliver the first three front ends Y 2007

Complete design of the service vehicle and handling equipment 03/2007

Deliver the holography transmitter and receiver 11/ 2006

Program Plan FY 2007 D. ALMA Construction 27

FigureD.7. FE Cryostat #1 and prototype chassis mounted on tilt table at the NA FEIC.

Back End IPT

The NA Back End IPT (BE IPT) plans to deliver antenna racks for the first antenna this year on schedule after having established a precedent by delivering Digital Transmission System (DTS) deformatter/optical receiver boards to the Correlator IPT and modules to the FE IPT for the holography system, all to meet schedule. In addition to completing documentation, procurement, construction, and testing tasks for the pre-production racks, the BE IPT will continue to support the Prototype System Integration (PSI) Group in testing a full complement of BE prototype modules delivered for testing at the ATF.

In the DTS area, the IPT is scheduled to complete testing and documentation of firmware revamped to support the 1/2 transponders and to correct various clock-synchronization problems uncovered by PSI testing. Because of the sophistication of the entire digital design, further design changes and firmware updates are anticipated as PSI testing progresses.

Figure D.8. The new optical “½ transponders” occupy 1/3 of the DTS deformatter board but save construction of three separate circuit boards.

Program Plan FY 2007 D. ALMA Construction 28

The pre-production IF Processor (IFP) modules (two per antenna) are scheduled to be assembled and tested from units that were partly manufactured by a vendor and partly built in-house. It may be necessary to add a gain equalizer to the IFP depending on the final system technical requirements, and the information is on hand to respond to that potential requirement.

T001-G009: IFDC Bandpass [S1→A, LO2 @ 14 GHz] 30 29 28 Lower-Edge -3dB Point: Upper-Edge -3dB Point: 27 2.0826 GHz 3.9450 GHz 26 25 24 23 22 21

] 20 19 HighBand 18 LowBand Gain-Slope (High) 17 Gain-Slope(Low) 16

IFP Gain [dB 15 14 13 12 11 Lower-Edge -20dB Point: Upper-Edge -20dB Point: 10 1.9321 GHz 4.0581 GHz 09 08 07 06 05 1.80 2.00 2.20 2.40 2.60 2.80 3.00 3.20 3.40 3.60 3.80 4.00 4.20

Baseband Frequency [GHz]

Figure D.9. The output bandpass performance of the IF downconverter meets current system technical requirements.

In the 2 GHz LO Reference and Timing area, the IPT is scheduled to complete testing of modules revised to correct a phase-drift problem and phase-ambiguity problems, both uncovered during PSI testing. A temporary Central LO rack to support 125 MHz and TE references during single-antenna tests at OSF is scheduled for shipment in October 2006.

The Photonics LO Product Group is scheduled to enter production procurement of the Master Laser and Laser Synthesizer assemblies, test the prototype Central Variable Reference (CVR) and decide on development of CVR production units, design the photonics distribution for the Central LO, complete plans and specifications for on-antenna and Central LO fiber-optic cable wiring, update the design and test the on-axis antenna wrap for the LO fiber-optic cable, and complete layouts for the Central LO equipment racks. Studies of phase-noise and stability requirements are scheduled to continue for a best effort in meeting the most demanding of project technical requirements. The target is to deliver a Central LO in FY 2008 sufficient to support the first eight antennas.

All pre-production bin and module hardware is scheduled to be procured and assembled, including rack- side connectors and inter-module cabling for antenna racks. The antenna racks and hardware are scheduled to be configured for shipment to Chile for the first antenna in FY 2007. The power-supply hardware and modules, completed for the first antenna, are schedule to be constructed for the Central LO. An air-flow and thermal analysis completed in the lab is scheduled to be verified as practicable for racks at ½ atmospheres pressure. Additional thermal performance tests of BE antenna racks are planned during antenna acceptance tests. Finally, completed designs for seismic-rated rack anchoring in the AOS TB are scheduled to be forwarded to the Site IPT for implementation.

Program Plan FY 2007 D. ALMA Construction 29

Table D.5. Back End IPT Milestones Item Delivery Date Ship pre-production antenna racks with supporting documentation and acceptance tests to OSF for the first Early CY 2007 antenna Complete testing and documentation of DTS firmware to support the 1/2 transponders and to correct various clock- 10/2006 synchronization problems uncovered during PSI testing Complete testing of pre-production IF Processor modules 01/2007 Complete testing of the LORR for the 2 GHz LO Reference 10/2006 Place order for the Master Laser and Laser Synthesizers 11/2006

Correlator IPT

The ALMA correlator performs digital filtering, delay adjustment, and cross-correlation calculations on the digital signals received at the AOS building, at a rate of 96 Gbit/sec for each of the antennas. The net computation rate for the cross-correlation section is 1.7 x 1016 multiply-and-add operations per second.

In FY 2007 the ALMA Correlator IPT will disassemble the first (or possibly second) quadrant, package it, ship it to Chile, install it in the AOS TB, test it, and hand it over to the AIV team. In addition, the assembly and test of the second quadrant will be completed. The partially assembled third quadrant will be moved into the correlator test room at the NTC and integrated testing will begin. The operational software and firmware needed for initial operation in Chile will be further enhanced and refined. Finally, the use of the two-antenna prototype correlator for Prototype System Integration (including interferometry) at the ATF will be supported by the Correlator IPT.

Table D.6. Correlator IPT Milestones Item Delivery Date

Install a quadrant of the correlator at the AOS TB and make it operational 08/2007

Ship test fixtures to Chile and set up support laboratory 08/2007

Complete assembly and test of the second correlator quadrant 02/2007

Begin integrated testing of the third correlator quadrant 11/2006

Computing IPT

Within the ALMA Computing IPT (CIPT) the NRAO has primary responsibility for overall IPT management, control and correlator software, offline data reduction (CASA), pipeline processing, dynamic scheduling, and software testing. In addition, the NRAO personnel participate in the technical development of the ALMA Common Software, high-level analysis and design, integration test and support, science software requirements, and software engineering. Some additional information on Offline (CASA) computing is presented elsewhere in this document.

Program Plan FY 2007 D. ALMA Construction 30

Figure D.10. Pipeline Quicklook display— screenshots of recent developments of some quicklook (operator) pipeline screens. These are with simulated data.

In FY 2007 the first priority for the CIPT will be to support the AIV process in Chile, since it defines the global critical path for the ALMA project. Besides general support software (e.g., monitor-point archiving), the major required functionalities for this are optical pointing, beacon holography, and continuum single dish (possibly with a nutator). The next priority will be to support first fringes at the ATF using lower-level control software, to be followed by single-field interferometry, which differs from first fringes in that it is a complete end-to-end observing mode (observing tool to archive to data processing with CASA).

In addition the work to prepare for later commissioning stages, early science, and final operations will continue apace. For example, in FY 2007 we will have the first end-to-end (flagging to imaging) test of the science pipeline.

Program Plan FY 2007 D. ALMA Construction 31

Figure D.11. Offline (CASA) user test 2,3 results—Deconvolved VLA interferometric mosaic, BIMA mosaic and 12m single-dish data combination and deconvolution (spectral line), and VLA mosaic with GBT single-dish data combination (continuum).

Table D.7. Computing IPT Milestones Item Delivery Date Make a major software release, including antenna acceptance software (beacon holography, optical pointing) and ATF first- 12/2006 fringes support. Procure OSF temporary building hardware and perform hardware 01/2007 and software installation. Make a minor software release, including AIV single-dish software and single-baseline single-field interferometry (unlike 06/2007 first fringes, this is an e2e software system—observing tool to archive).

Program Plan FY 2007 D. ALMA Construction 32

Figure D.12. Correlator setup tool, including location of ALMA bands, spectral lines, and atmospheric transmission. This is part of the ALMA Phase 2 program preparation tool.

Systems Engineering & Integration IPT

The work of the ALMA Systems Engineering and Integration (SE&I) IPT is divided into four parts with the main activity as follows:

System Engineering ESO task Product Assurance NRAO task Prototype System Integration (PSI) NRAO task Assembly, Integration & Verification JAO task

In the System Engineering area, NRAO staff will support the ESO-led effort by helping clarify requirements documents and the system description and by serving on design review panels.

The position of Product Assurance lead engineer, which was held by Jeff Zivick until he left SE&I to head the NA Antenna IPT, was filled in July 2006 by Mike Rodriguez. One of his first jobs will be to review the Statements of Work for the project, looking for disconnects and missing tasks.

In the area of Prototype System Integration, by the start of FY 2007, the prototype hardware should be installed on the antennas at the ALMA Test Facility (ATF). The next task of the PSI group will be to re- establish system connectivity at the ATF. This will be demonstrated by achieving auto-correlation spectra of a signal from an astronomical source and interferometry on a radio beacon. The next step will be to demonstrate two-antenna interferometry on an astronomical source with phase tracking of that source across the sky. Then the PSI group and the Science Commissioning group will jointly determine if the system functional requirements are met. The PSI group will then support science commissioning and calibration.

Program Plan FY 2007 D. ALMA Construction 33

The PSI group will support and facilitate the use of the ATF by other IPTs wishing to use it as a test bed for first-issue hardware and software. We anticipate testing the optical pointing telescope, golography and some software components are during FY 2007.

The PSI group will plan and implement a program for training AIV, CSV, and OPS staff at the ATF.

Assembly, Integration & Verification (AIV) of the ALMA array is the task in Chile led by the JAO Project Engineer. In FY 2007 the first integration team will be formed, and the first ALMA antenna will be accepted and outfitted in Chile at the OSF.

Table D.8. Systems Engineering & Integration IPT Milestones Item Delivery Date

Re-establish system connectivity at the ATF. Q4 2006 Demonstrate two-antenna interferometry on an astronomical source Q2 2007 at the ATF. In conjunction with antenna, front-end, and computing IPTs, coordinate and execute the installation and verification of the Q4 2006 optical pointing telescope and holography systems at the ATF so that these systems may be sent to AIV in Chile by the end of 2006. Train AIV, CSV and OPS staff at the ATF. Q4 2006

Figure D.13. Gene DuVall, seated between a Vertex analogue rack and a phase-noise test-set rack. (24 Mar 2006).

Program Plan FY 2007 D. ALMA Construction 34

Figure D.14. PSI in AOC lab, from L to R a) Alcatel analogue rack, b) RF (FE) simulator rack, with on-axis cable wrap in front, c) Central LO rack, d) Vertex analogue rack, e) Gene DuVall, and f) phase-noise test-set rack. (24 Mar 2006).

Figure D.15. Front of Vertex digital rack with three of four DTS Transmitters and the Digitizer Clock module. Not yet ready to move to the ATF. (24 Mar 2006).

Program Plan FY 2007 D. ALMA Construction 35

Figure D.16. Front of Vertex digital and analogue racks. (24 Mar 2006).

Science IPT

As the design of the road and fiber network at the Array Operations Site is completed, synergistic design of the longest-baseline pad locations in ALMA can be finished. This task is dependent on the network design, expected to be completed as FY 2006 draws to a close. A call for elements of the Design Reference Science Plan (DSRP) including the use of ALMA components furnished by Japan has been issued. The response to this call will be developed into DRSP v2.0 during the first quarter of FY 2007.

Figure D.17. This figure (by Françoise Combes) shows the detectability of various aspects of a Milky Way-type galaxy at high redshift as viewed by different instruments. ALMA's capability to measure the CO lines is evident; continuum and [C II] are detected at submm wavelengths.

Program Plan FY 2007 D. ALMA Construction 36

In FY 2007 the ALMA Science IPT expects to be moving toward execution of commissioning activities as a part of Prototype System Integration. A primary goal will be to evaluate elements of the calibration system deployed at the ATF. This will include amplitude calibration with the ALMA front ends and the calibration devices mounted on the front of the dewar, including hot loads for amplitude calibration. Most design reviews will be completed and the focus will move toward commissioning of the instrument, particularly as the JAO Project Scientist begins work in Chile. Two Commissioning Scientists will join the Project Scientist, and many elements of pre-commissioning Work Breakdown Element 3040 will be closed, and the Work Breakdown Element 3070, implementation of commissioning, will begin.

Results of testing the ALMA water-vapor radiometers at the Submillimeter Array (SMA) on Mauna Kea, including phase correction, will be presented at a meeting in Wettzell, Germany in October 2006.

Figure D.18. This trace shows the raw phase and the raw phase minus the estimate from the water- vapor radiometers with arbitrary vertical offset but no multiplicative adjustments. The data were taken at 230 GHz.

Community involvement with ALMA will continue through an AAS town meeting in Seattle, ALMA workshops at the NAASC (on protostellar and protoplanetary disks, now in planning stages), and at other venues.

Table D.10. Science IPT Milestones Item Delivery Date Demonstrate early calibration of the complete ALMA system during Prototype Systems Integration at the ALMA Test Q4 2007 Facility. Deliver version 2.0 of the Design Reference Science Plan, including ALMA components furnished by Japan. 12/2006

Program Plan FY 2007 D. ALMA Construction 37

E. EVLA Construction

Accomplishments and Highlights in FY 2006

The subsections below correspond to the major elements of the EVLA project’s work breakdown structure (WBS).

Project Management

The EVLA Advisory Committee met on May 8–9, 2006 to review progress on the project. The major recommendations of the committee included developing more quantitative performance metrics for the project, conducting a detailed risk and contingency analysis, closely monitoring the delivery of the WIDAR correlator, accurately determining data-throughput requirements between the correlator and the monitor and control system, and exploring collaborations with ALMA to make significant reuse of ALMA software. An NSF Mid-Project Review was held on May 11–12, 2006. The review committee suggested that another review be held in late 2007, possibly in conjunction with the Advisory Committee meeting, to review progress on important milestones (e.g. installation of the prototype correlator and retrofitting a total of 12 antennas to the EVLA design).

In early 2005 the Mexican CONACyT issued a contract to the NRAO for constructing equipment including complete sets of electronics for two antennas plus K- and Q-band receivers. The equipment was built and presented to Mexican UNAM representatives, who visited the VLA site in November 2005. The total Mexican funding of $1.746M was received and deposited into the NRAO EVLA account.

Peter Napier stepped down as EVLA Project Manager in January 2006 to take on a new role as an ALMA Systems Integration Engineer. He was replaced by Mark McKinnon.

Systems Integration

A total of six VLA antennas are in various stages of retrofit to the EVLA design. Four EVLA antennas are now functioning with four complete IFs. These antennas are equipped with receivers for L, C, X, K, and Q bands; and they are being used by the scientific and technical staff to evaluate the performance of the EVLA hardware and software. By August 2006 all four antennas will be returned to operations so that they can be used in scientific observations by both the NRAO and external users. The fifth antenna has been outfitted with EVLA electronics and is operating with two IFs at X band. The remaining IF pair will be installed in the antenna in July. The mechanical outfitting of the sixth antenna is complete, and it will be outfitted with electronics throughout the months of July and August.

In mid–2005 antenna retrofitting was temporarily suspended in order to allow project staff to focus on outstanding design issues, electronics reliability issues, and testing and debugging activities. By December 2005 sufficient progress was made in these areas so that antenna retrofitting could resume.

Civil Construction

The installation of the RFI-shielded room for the new correlator was completed in December 2005. The shielding effectiveness of the room was tested and verified, and the tightness of the room was checked as part of a fire-suppression contract. The installation of the room’s fire-suppression system, HVAC system, electrical power distribution, and lighting are complete. The installation of the room’s computer flooring will be complete in August 2006.

Program Plan FY 2007 E. EVLA Construction 38

Antennas

The mechanical overhaul of two EVLA antennas was completed in FY 2006. The fabrication of mechanical components, such as platforms and feed towers, for the next three EVLA antennas has begun.

The fiberglass lamination of 12 L-band feed horns has been completed, and the lamination of horn 13 is in progress. These feed horns are assembled at a fiberglass shop in Albuquerque at the rate of about eight per year. Storage fixtures for the L-band feed horns were designed, and the first of four fixtures has been built and utilized. All but three of the C-band feed horns have been assembled and stored in the warehouse.

Front End

The critical design review (CDR) for Front-End Systems was held on April 24–25, 2006. Overall, the CDR panel felt that the definition of the front-end requirements was comprehensive and realistic, and that for the most part the designs selected appear to meet the Project Book requirements, thus allowing hardware production to proceed in most areas. The panel was impressed with the efficiency of the cryogenic developments and indicated that the front-end test facilities were well thought out and effective. Several suggestions were provided for reducing the excess noise measured in the L-band prototype orthomode transducer (OMT). Finalizing the OMT design is extremely important to the project schedule because the L-band OMT design will be scaled for use in the S- and C-band receivers. The panel also made a number of general recommendations, including the need to apply more technical resources to the L-band OMT, carrying out further investigations of waveguide window material, and reviewing the protection circuits used for the indium phosphide (InP) low-noise amplifiers.

The L-band receivers currently in use on the EVLA antennas are the old narrowband VLA receivers modified for use with the new EVLA feed horns. The new prototype L-band receiver has been assembled and is undergoing vacuum, thermal, and RF performance tests.

Prototype feed horns for the other receiver bands are being developed. A half-sized S-band prototype feed was tested on an outdoor antenna-test range located on the New Mexico Tech campus. The measured beam patterns and VSWRs agreed well with theoretical projections. The X-band receivers currently installed on the EVLA antennas are the old receivers taken from the VLA antennas. The installation of production EVLA X-band receivers will occur late in the project. Two prototype horns for the production X-band receiver were built and tested in Green Bank.

Local Oscillator (LO) Systems

All LO modules are in or moving into full production. Round-trip-phase measurement modules (L352) are being tested on the EVLA antennas to determine if the modules are achieving the required phase- measurement accuracy. Initial test results indicate that the L352 meets its specifications. Delivery of the L301 and L302 frequency synthesizers was completed in November 2005. Antenna performance measurements showed that dropouts in visibility amplitude and the inability to retain phase on a change in frequency were attributable to the L302. The source of these problems was multi-faceted, but the problems were finally resolved by configuring the synthesizer to ensure the proper phasing of the antenna’s Walsh function whenever the frequency was updated. The installation of all master LO modules in the control building will be finished in late 2006 when the central reference generator (L350) and master offset generator (L351) are completed.

Program Plan FY 2007 E. EVLA Construction 39

Fiber Optics Systems

Because of the early retirement of a fiber-optics technician, only 35 of the 72 stations on the array were completely cabled with optical fibers for LO, IF, and Ethernet connections. Fiber-optic pad boxes were set at the 35 antenna pads, and fiber splices were made to the boxes. The fiber to each pad has been tested, and its losses have been documented. The 37 remaining stations will be cabled with optical fiber in 2007.

In mid–2005 the formatter and 8-bit digitizer boards in the Digital Transmission System (DTS) module had to be redesigned. The new design was fabricated and successfully tested, allowing the full production of the DTS modules to proceed. Construction of the DTS modules, the formatter, and the de-formatter continue to meet the antenna outfitting schedule. Procurement of the half transponders for all DTS modules was completed.

The prototype design of the 3-bit, 4 GHz sampler is complete, and a circuit card for the sampler has been designed, built, and received. The board will be populated and tested in August 2006 when the Rockwell digitizer chip arrives. This prototype design will be used to help the project determine whether it will use the Rockwell-based design or an existing ALMA design.

Intermediate Frequency (IF) Systems

The three frequency converters [for the 4P (T301), LSC (T302), and UX (T303) bands] that up- or down- convert RF signals from the antenna receivers to the 8–12 GHz IF of the EVLA were designed, prototyped, and placed into production. Image-rejection problems found in the T301 and the baseband downconverter (T304) were solved by the installation of new filters. Excess instrumental noise recently identified with antenna performance measurements is being attributed to the T302 or T304. The antenna performance measurements have also revealed spurious emissions (tones) in EVLA passbands that are currently thought to arise in the T304. Additional tests are underway to determine the sources of the noise and the tones so that the module designs can be modified to eliminate them.

Correlator

The design of the new correlator chip was released for production in December 2005. Ten packaged correlator-chip prototypes were delivered to Penticton in June 2006. These prototypes will be tested to ensure there are no packaging problems before the 200 remaining prototypes are packaged.

A manufacturer was selected for the fabrication of all printed-circuit boards for the correlator. The initial attempt to fabricate the baseline board for the correlator chips was not successful because of an error in stacking the board layers at the fabrication plant. The internal layers of the board were redesigned to fix this problem. The error has caused a three-month delay in the fabrication and assembly of the baseline board. The order for the first station-board prototype was placed, with an expected delivery of September 2006.

Monitor and Control (M&C)

An interim Observation Executor is now used more widely and supports even more capabilities than can be specified in a VLA Observe file. VLA operators, some astronomers, and some engineers now use a web-based interface to the Observation Executor to submit jobs for EVLA antennas. EVLA antennas have been included in some of the standard observing sessions, such as the pointing runs used to determine the coefficients in the antenna-pointing models. Requirements for the final version of the Observation Executor were developed in May 2006.

Program Plan FY 2007 E. EVLA Construction 40

Another area of significant progress has been the development of software to enable the EVLA antennas to participate in transition-mode observing with the VLA antennas and correlator. Software is now available to allow the observer and array operator to include EVLA antennas in most standard-observing- mode experiments. A few specialty observing modes, such as planet tracking, are not yet implemented.

A number of other important milestones were achieved by the M&C group in FY 2006. A production version of an interim Antsol/Telcal program that makes complex antenna gains and on-the- fly pointing offsets available to the EVLA M&C system was completed in March 2006. Test and verification plans were produced to specify the software needed to support the testing of the prototype station and baseline boards for the new WIDAR correlator. Development work has begun on Interim Data Capture and Format (IDCAF), the software that will format and write VLA-format archive records from the M&C system. The final version of the Module Interface Board (MIB) that allows communications between electronics modules and the M&C system was designed, tested, and released for production.

Data Management

The hiring of two software engineers allowed work to proceed on the High Level Architecture (HLA) for EVLA Science Support Systems (SSS) software. The HLA effort continues to concentrate on the development of models for its various components. The first application to use these models was the Observation Preparation Tool (OPT). The first release of the OPT was made. A second release of the VLA Proposal Tool took place in May 2006, when 120 proposals were received. The scientific requirements for all SSS subsystems for the EVLA were examined in detail and re-prioritized. These requirements and their timescales will form the basis of EVLA software planning for the next five years.

The Interferometry Software Division (ISD) continued work toward the development of common EVLA and ALMA models in order to facilitate the EVLA's reuse of ALMA software. Work on the Science Data Model is satisfactory, but progress on the Project Model was delayed by more pressing commitments for both projects. Work is under way to use the ESO/ALMA storage technology for the VLA/VLBA archive.

EVLA Milestones

Table E.1 is the list of FY 2006 milestones for the EVLA given in the 2006 NRAO Program Plan, updated with the performance on those milestones.

Table E.1. Performance on EVLA Milestones from the 2006 Program Plan Item Planned Current Plan

Use EVLA antennas for routine VLA operation 6/2006 8/2006

New correlator shielded room complete 9/2006 8/2006

Complete top-level design of e2e software 5/2006 10/2006

Retrofit a total of 7 antennas to the EVLA design 9/2006 11/2006

Complete installation of array fiber infrastructure 9/2006 7/2007

Continue design/construction of EVLA corrrelator ongoing

Program Plan FY 2007 E. EVLA Construction 41

Plans for FY 2007

Project Management

Per the recommendations of the EVLA Advisory Committee, the project office will develop performance metrics for the project and conduct detailed risk and contingency analyses. An EVLA Science Advisory Committee will be formed to advise on the NRAO plans for first science observations, advertise EVLA capabilities to the astronomical community, and make recommendations on possible descope options if necessary.

Systems Integration

FY 2007 offers a significant challenge to the EVLA project in that 6 additional antennas must be retrofitted to the EVLA design to meet the project schedule. The rate of antenna retrofitting will proceed at 5–6 antennas per year through the third quarter of CY 2010.

Civil Construction

Civil construction on the EVLA project will be complete in the first quarter of CY 2007 with the installation of the correlator power plant in the shielded room.

Antennas

The major activity facing the antenna group in FY 2007 is the retrofitting of 6 antennas. The mechanical retrofitting includes removing all equipment in the existing vertex room of each VLA antenna, installing a new feed-cone housing on the vertex room, installing a new HVAC system for the vertex room, and fabricating and installing platforms for the HVAC condenser and a cryogenic compressor. The group will also need to ensure that eight additional L-band feed horns are delivered by the horn assembly contractor. Additionally, the Ka-band feed horns will be procured and a full size S-band feed horn will be built.

Front End

The highest-priority task for the Front End group is to improve the noise performance of the L-band OMT so that production of the L-band OMT and receiver can proceed. The group also needs to select a cost- effective means of fabricating the OMT. The production of C-band receivers will be well underway, and the first C-band OMT will be fabricated and tested. A prototype of the Ka-band receiver will be developed.

Local Oscillator Systems

Tests of the round-trip-phase measurement (L352) module will be completed, and production orders of L352 module components will be placed.

Fiber Optic Systems

All 72 array stations will be completely cabled with optical fiber for LO, IF, and Ethernet connections allowing EVLA antennas to be located anywhere in the array.

Program Plan FY 2007 E. EVLA Construction 42

A prototype sampler that uses the 3-bit, 4GHz Rockwell digitizer chip will be fabricated. The prototype sampler will be compared with the ALMA design, and the best design will be selected so that production orders of the sampler can be placed in the summer of 2007.

Intermediate Frequency Systems

Additional tests of the LSC upconverter and the baseband downconverter will be made to determine the sources of excess instrumental noise and spurious emissions so that any modifications to these modules can be designed and implemented.

Correlator

The EVLA’s Canadian partner, the Herzberg Institute of Astrophysics (HIA), will continue assembling and testing the baseline board and the station board with the goal of delivering a prototype correlator to the VLA site in September 2007. The critical design review for the full correlator is scheduled for June 2007.

Monitor and Control (M&C)

The top-level design document for EVLA M&C will be completed and the M&C critical design review conducted in November 2006. The data throughput and handling requirements of the full correlator and the M&C system will be determined.

Data Management

During the years 2007–2011 the major elements of the programs for Science Support Systems (SSS) are scheduled to progress through alpha and beta releases to a full release. The major SSS elements include the proposal tool, observation preparation tool, scheduling tool, science archive, pipeline, and observation status tool. Some of these elements will be completed in collaboration with the Observatory’s newly formed e2e Operations Division. In FY 2007 the development of the High Level Architecture will be mature enough that the SSS preliminary design review (PDR) can be conducted. The PDR is currently scheduled for November 2006. A software-integration test plan for tests of the prototype correlator will be developed in conjunction with the M&C group.

EVLA Milestones

Table E.2 summarizes the key EVLA deliverables for FY 2007.

Table E.2. EVLA Milestones for FY 2007 Item Delivery Date

Develop project performance metrics 10/2006

Initiate procurement of the Ka-band feed horns 10/2006

Complete design of High Level Architecture 10/2006

Complete design of the L-band OMT 10/2006

Complete M&C critical design review 11/2006

Program Plan FY 2007 E. EVLA Construction 43

Item Delivery Date

Complete Science Support Systems PDR 11/2006

Conduct risk and contingency analyses 12/2006

Assemble the prototype S-band feed horn 12/2006

Start production of L-band receivers 2/2007

EVLA Science Advisory Committee meeting 4/2007

Complete prototype of the Ka-band receiver 6/2007

Start production assembly of 3-bit samplers 6/2007

Conduct correlator critical design review 6/2007

Complete installation of array fiber infrastructure 7/2007

Retrofit a total of 12 antennas to the EVLA design 9/2007

Conduct an on-sky test of the prototype correlator 9/2007

Assemble a total of 20 L-band feed horns 9/2007

Program Plan FY 2007 E. EVLA Construction 44

F. Telescope Science Operations

1. North American ALMA Science Center

Accomplishments in FY 2006

FY 2006 marked a number of significant milestones for the fledgling NAASC. Paul Vanden Bout stepped down as NAASC Head in December, being replaced by Chris Carilli in May 2006. Crystal Brogan joined the NAASC in March 2006. The first NAASC Science Workshop was held in Charlottesville in January 2006 to a capacity crowd. The initial NAASC Staffing plan was developed and reviewed internally and presented to NSF in April 2006. Presentations and Town Meetings were given at each AAS meeting (January 2006 in Washington D.C.; June 2006 in Calgary) and to NRAO Committees and NSF. The NAASC staff together with interested parties from NRAO Operations and ALMA Construction participated in software tests of all the major user software systems (offline, pipeline and observing tool); work started on developing a spectral-line catalogue, and this prototype system was successfully interfaced to the ALMA Archive. More formal discussions with our Canadian partners were held to fully integrate them into the NA ALMA operations planning. The ANASAC was reconstituted to provide more focus and constructive input into the NAASC operations planning. Finally, the NAASC staff were instrumental in revising and updating the overall ALMA Operations plan and budget.

NAASC Activities in FY 2007

The NAASC tasks to be accomplished in FY 2007 continue the organization and planning of FY 2006 with growing emphasis on tasks such as software testing, community relations, and preparation of observing tools. There will be eight FTE positions supported by ALMA operations funds, including the NAASC head, the ARC director, a support scientist, a part-time secretary, and four CASA programmers. The following list is a summary of the principal tasks for FY 2007.

Submission of a revised ALMA operations plan for review by the ALMA board in November 2006

The revised plan will represent the trilateral rebaselined project. John Hibbard, the ARC manager, NRAO, will work closely with the JAO and the other executives in this process.

Submission of a funding proposal for North American ALMA operations and the NAASC to the NSF in November 2006

The ALMA operations funding proposal will be based on the global operations plan and include North- American-specific requirements for science support. Internal reviews by the NRAO and AUI will be held prior to submission to the NSF in November 2006. An NSF review expected in CY 2007 will include a general review of global ALMA operations. We have and will continue to study the operations of the Hubble, Spitzer, and Chandra science centers and are in close contact with the team planning the Herschel science center.

Engage the ANASAC as the conduit to the U.S. community

The ANASAC has been formalized as the primary input from the North American scientific community to the ALMA project via the NRAO for key issues such as future ALMA development projects, a potential program of grants with observing time, and a review of the NAASC proposal to the NSF.

Program Plan FY 2007 F. Telescope Science Operations 45

Regular telecons are held in addition to an annual face-to-face meeting. In the next year we also hope to establish, through the ANASAC, an exchange program of NAASC and university scientists in cases that benefit ALMA development and educate the user community.

Software Testing

The emphasis in FY 2007 will be testing the proposal submission tool, the pipeline data-reduction system, and the user interface to post-processing software. These software tests are part of the regular schedule of tests organized by the ALMA Computing IPT and the e2e Operations Division. NAASC staff participate to provide external reviews of the software and to gain experience in its use.

Community Relations

The principal activity in this area is to keep the community informed on the status of the ALMA project, building interest while managing expectations. A town meeting will be held at the Seattle meeting of the AAS in January 2007. [A special session was organized at the 2006 summer meeting of the AAS in Calgary.] We are planning a scientific meeting in Charlottesville on “Protoplanetary Disks” in the spring of 2007. We also hope to support a spectral line lab astrochemistry workshop at Caltech in October 2006. We anticipate that the current series of summer schools on aperture-synthesis radio astronomy now held every two years at the NRAO in Socorro will evolve into a program with a larger emphasis on millimeter wavelengths and ALMA-specific tutorials.

Database Construction

Databases of spectral-line frequencies and phase-calibration sources are required. Work has begun on a spectral-line frequency table for a large number of known and possible interstellar molecules to aid observers in planning and interpreting their observations. The goal is to build the frequency table into the observing/proposal tool and to have it available on-line for widespread and easy access by users. Work on this table and its web interface will continue in FY 2007.

ALMA Data-Analysis Software

ALMA construction has funded the development of the ALMA data structures, data-flow process, and some basic data-analysis routines using CASA software. In FY 2007 the NAASC will support four FTE programmers working on CASA software to complete the suite of analysis tools needed for ALMA scientific use cases. The lead times for astronomical software are long, and we consider this activity to be essential to the success of ALMA as a scientifically productive and user-friendly facility.

Education and Public Outreach (EPO)

The ALMA component of the NRAO EPO program will concentrate on improving the website. In addition, work will continue on supporting an ALMA presence at scientific meetings, development of brochures and displays, and issuing press releases as appropriate.

Canadian involvement in ALMA operations

We will formalize a series of telecons and an annual face-to-face meeting to determine the Canadian contribution to ALMA operations.

Program Plan FY 2007 F. Telescope Science Operations 46

University of Virginia (UVa) Foundry Work

The NAASC is supporting the silicon foundary work at the UVa. For ALMA and the U.S. community it is vital to maintain a state-of-the-art capability in submm receivers. The UVa microfrabrication lab is a major resource for U.S. astronomy and for ALMA. It is one of only two sources for superconducting millimeter-wave devices. In the short term, repair and maintenance of existing receivers at the integration center may not be feasible in many cases as only the maker of the SIS receiver is qualified to repair it and return it to its original specifications. In the long term, ALMA hopes to continue to improve the capability of its receivers by reducing 1/f noise for total-power measurements and, at the highest frequencies, developing new receiver technology to approach the quantum noise limit.

Work with the NRAO e2e on Archive and VO tasks

We have begun extensive discussions with the e2e Operations Division of the NRAO to consider the design of the NRAO archive and VO interface. The discussions have the eventual goal of producing an NRAO-wide science data archive.

Goals for the NRAO-Chile office for 2007

The NRAO Chile office supports ALMA operations as well as construction activities. In addition to the 2007 activities summarized under ALMA construction section, a comprehensive plan for academic exchanges and collaboration with local universities, as well as local EPO on behalf of the NRAO and ALMA, will be implemented.

Program Plan FY 2007 F. Telescope Science Operations 47

2. Green Bank Telescope (GBT)

Introduction

The Robert C. Byrd Green Bank Telescope (GBT) is the world’s premiere single-dish radio telescope operating at centimeter–millimeter wavelengths. The GBT is in robust, routine, and effective operation at frequencies up to 50 GHz. Approximately 6300 hours of telescope time were scheduled for astronomy programs during the year. This represents 72 percent of the total time and an increase of 9 percent from FY 2005. Highlights of FY 2006 include the full release of the ASTRID and GBTIDL software packages for observing and data-reduction respectively, completion and commissioning of the Caltech Continuum Backend, and significant telescope surface improvements via “out-of-focus” holography.

Figure F.2.1. The Robert C. Byrd Green Bank Telescope.

GBT receivers provide nearly continuous frequency coverage from λ = 1 m to 6 mm (0.29 to 50 GHz) with on-sky system temperatures as low as 15 K. The GBT spectrometer is a multilevel digital correlator providing 2,048 channels in each of eight 800 MHz spectral bands or up to 262,144 channels at 12.5 MHz bandwidth. The Zpectrometer, a redshift machine with 14 GHz instantaneous bandwidth at 26–40 GHz, is under construction. Three fast-sampling backends provided by university collaborations are available for pulsar observers. The Penn Array 64-element bolometer camera for λ = 3 mm (92 GHz) is due to be commissioned in fall 2006.

The primary mission of Green Bank Operations is to operate the Green Bank Telescope for the benefit of the scientific community, to facilitate the scientific results of GBT users, to enhance the GBT’s scientific capabilities through a continuing development program, to support and develop the single-dish radio astronomy community through student initiatives, cooperative instrumentation development, and university outreach programs, to support and promote the research of the NRAO scientific staff, and to administer and preserve the National Radio Quiet Zone.

Program Plan FY 2007 F. Telescope Science Operations 48

The secondary mission of Green Bank Operations is to provide Observatory-wide support facilities such as the Central Instrument Shop and Antenna Test Ranges, to support Observatory-wide operating units located in Green Bank (e.g., Fiscal, MIS, and Safety Divisions), to contribute effort and expertise to other Observatory projects and the overall Observatory mission whenever possible, to effectively manage, preserve, and develop the Green Bank site and physical plant, to utilize and develop other Green Bank Observatory assets (e.g., other telescopes) as appropriate, to support an active education and public outreach program for the region in concert with the EPO Division, and specifically to support local education and community development as feasible and appropriate.

Progress toward FY 2006 Program Plan Objectives

Staffing and Budget

Phil Jewell departed Green Bank in June 2005. Richard Prestage served as Interim Assistant Director and was confirmed as Green Bank Assistant Director on February 1, 2006. Given the budget pressures on staffing, the Deputy Assistant Director position has not been refilled. Rather, in order to provide improved focus on excellence in operations, and effective management of the GBT development program, we have defined three key positions which have been filled via internal staffing reassignments. The GBT Principal Scientist (Jay Lockman) will provide advice and assistance to the Green Bank Assistant Director and the NRAO Director on issues related to the scientific priorities for the GBT and its wider role in the Observatory and in the U.S. astronomical community. The Head of Science Operations (Ron Maddalena) will be responsible for the day-to-day scientific operation of the GBT and for providing guidance to technical staff on responding to faults and other operational issues. The Head of GBT Program Development (Karen O’Neil) will coordinate the definition and execution of the Green Bank strategic- development program.

Professional staffing numbers continue to decline. In addition to the Deputy Assistant Director position, during FY 2006 we have absorbed the loss of one software-engineer position, an RF engineer from the Interference Protection Group, and three digital engineers. In part this is the result of the overall pressure on the NRAO budget; in part it is to support a redirection of funds in FY 2007 to the Observatory-wide strategic development initiative (although some fraction of this will support continued GBT development work). The overall impact of these changes is that GBT development work will proceed more slowly than we would like.

Observing Software

ASTRID (the ASTRonomer's Integrated Desktop) is a unified workspace that incorporates the GBT’s new scheduling-block-based observing system with the real-time quick-look display. ASTRID allows observers to build observing scripts as part of their scheduling blocks well in advance of their observations. The full release of ASTRID, including source catalogs, support for non-sidereal sources, and control of the pulsar spigot, was completed as planned in early FY 2006. All observations are now performed using Scheduling Blocks and ASTRID, and this new interface has proved extremely successful and very popular with astronomers. Multiple Scheduling Blocks are managed by individual observers through ASTRID’s current scheduling-block database interface. Although fairly minimalist, this solution appears adequate until full dynamic scheduling is implemented. All of this work was essentially completed as planned.

Program Plan FY 2007 F. Telescope Science Operations 49

Data Analysis Software

GBTIDL is the interactive package for reduction and analysis of spectral-line data taken with the GBT. GBTIDL development continued during FY 2006, and GBTIDL is now at release 2.0.1 and considered mature. As planned, the IDL algorithms have been made available to the quick-look data display, so that GBT data for all continuum and spectral-line observing modes are now displayed in real time by a single software application. A generic flagging solution has been developed and was released with GBTIDL Version 2.0.

Unfortunately, because of a reduction in the size of the GBT Software Development Division and pressures on the scientific-support staff, the planned work to migrate support for imaging applications to the software group and to refine calibration approaches and software for all standard GBT observing modes was not completed during FY 2006. No significant progress was made on the Science Data Model.

Heterodyne Instrument Program

High-Frequency Receivers: The Ka-band (26–40 GHz) and Q-band (40–50 GHz) receivers were released as planned for Winter 2005/2006. Early science and commissioning observations at the start of FY 2006 revealed intermittently poor spectral-baseline performance with both receivers. Given these problems, in November 2005 observations were restricted to Q-band narrow-line and Ka-band continuum, which could be successfully performed with the available receiver performance. The baseline problems are being investigated. They may result from intrinsic properties of the low-noise amplifiers. If this is the case, faster switching with the existing receiver can ameliorate the effects at Ka band, but the Q-band receiver may require a major hardware redesign. Despite these problems, the straightforward retrofits to the Q- band receiver to restore the full 40–50 GHz bandwidth and to the Ka-band receiver to accommodate the Zpectrometer are being performed as scheduled during summer 2006.

Caltech Continuum Backend (CCB): The CCB is a collaborative project between Caltech and the NRAO to develop a fast-switching high-sensitivity continuum backend for use with the Ka-band and future W- band (λ = 3 mm) receivers. This backend is capable of analyzing essentially the full bandwidth of each receiver, with the bands broken into three or four sub-bands to allow some spectral analysis. CCB development was funded as part of the Observatory’s University-built Instrumentation Program. The first CCB unit, for use with the Ka-band receiver, was completed and commissioned as planned in the last quarter of 2005. Extremely successful science observations were performed in spring 2006. The second and third units (for the W-band receiver and a spare) will be completed in FY 2006. This will finish the project.

Zpectrometer (Wideband Spectrometer): The Zpectrometer is the wide-band analog spectrometer under construction by Prof. Andy Harris at the University of Maryland. Green Bank staff will provide software development, interfacing, and other support. The Zpectrometer covers the full 14 GHz-wide Ka band with a set of analog lag correlation spectrometers in a multichannel correlation-radiometer architecture. The Zpectrometer's bandwidth and stability, combined with the GBT's collecting area, enable sensitive and efficient spectral searches for molecules in high-redshift galaxies. The instrument is optimized for observations of low-excitation spectral lines from the carbon monoxide (CO) molecule at redshifts of 1.88 < z < 3.43 and 4.76 < z < 7.87. These ranges of redshifts are of intense current interest because they may correspond to the eras when most of the stars in the universe formed and when galaxies were assembled, respectively. Development work for the Zpectrometer began as planned in FY 2006, and the preliminary instrument commissioning should commence in early FY 2007.

Program Plan FY 2007 F. Telescope Science Operations 50

Penn Array Camera

The Penn Array is a 64-pixel bolometer camera for the λ = 3 mm band that is being developed by a consortium of the University of Pennsylvania, NASA-Goddard, NIST, Cardiff University, and the NRAO, and funded largely through the NRAO University-built Instrumentation Program. The camera has an 8 × 8-pixel array with full spatial sampling; the field of view is approximately 30” × 30” and the angular resolution is about 8” per pixel. The detector array is made up of state-of-the-art Transition Edge Sensors (TESs) with SQUID multiplexers, all cooled to a cryogenic temperature of 0.25 K. The sensitivity of the array should be better than 500 µJy//sec per pixel.

The initial engineering commissioning was to occur in the spring of 2006, but problems with the detector array caused a delay. These problems are now understood, and the project underwent an extremely successful In-Progress Review in August 2006. Engineering commissioning is now scheduled for early fall 2006.

Precision Telescope Control System

As expected, little progress was made on the Precision Telescope Control System (PTCS) project in FY 2006. One significant milestone was the completion of the “out-of-focus” holography campaign designed to correct the elevation-dependent surface deformations. This work was extremely successful and resulted in a new model for the surface, now in routine use, which flattens the gain-elevation curve at all observing frequencies. Work on the PTCS will resume in earnest in FY 2007.

Azimuth Track Refurbishment

As planned, all contracts for the azimuth track were placed in FY 2006. This work remains on schedule for completion in summer 2007.

RFI Mitigation

The National Radio Quiet Zone (NRQZ) remains a unique National resource, and we have renewed our commitment to preserve our relatively RFI-free environment to the greatest extent possible. Recent outstanding pulsar discoveries resulted directly from the low RFI in Green Bank and provide a compelling argument as to why this work remains vital. Recent progress includes development of five zones around the GBT within which clear RFI policies have been defined and documented, installation of an abbreviated version of the GBT RFI monitoring station, hiring of a new NRQZ administrator, and the start of a public-relations campaign to raise awareness of RFI issues in the local community via newspaper, radio, and direct mailing. In addition, material is being developed and distributed to communicate on-site RFI policy (signs, leaflets, web-based material, presentations), and mitigation efforts are underway for all on-site telescopes and projects. The RFI group is also facilitating a collaborative propagation-model study with Virginia Tech and the Naval Surface Warfare Center.

Externally Funded Projects

In FY 2005, the NRAO and Lincoln Laboratories entered into a collaborative agreement to measure the properties of the Earth's ionosphere using bi-static radar techniques. The project consists of two phases: (I) System Development and Implementation, and (II) Operations. Phase I was completed to budget and schedule in March 2006. Phase II is proceeding and we currently expect this to continue at least through FY 2007.

Program Plan FY 2007 F. Telescope Science Operations 51

We continue to support a number of other externally funded projects on the Green Bank site, providing infrastructure support and, in some cases, a modest level of staffing funded by the relevant project. These include the Solar Radio Burst Spectrometer (SRBS) and the Precision Array to Probe the Epoch of Reionization (PAPER).

A summary of performance against milestones in FY 2006 for all GBT Projects is provided in Table F.2.1

Table F.2.1. Performance on GBT Milestones from 2006 Program Plan Item Planned Accomplished Initiate 43m MIT/LL test observations 10/2005 10/2005 Q-band production science begins 10/2005 10/2005 (see note) Initiate Zpectrometer instrument construction 11/2005 11/2005 Ka-band spectral line commissioning complete 11/2005 11/2005 (see note) Begin CCB commissioning 12/2005 11/2005 Integrate pulsar spigot control into std observing 12/2005 10/2005 AZ track refurbishment contracts let 12/2005 4/2006 Initiate Penn Array /3mm engineering tests 02/2006 09/2006 (planned) Agree dynamic scheduling policies and processes 05/2006 06/2006 Finalize GBT Science Data Model 09/2006 Moved to FY 2007 Publish dual feed PF feed test results 09/2006 Moved to FY 2007 Full Q-band bandwidth restored 09/2006 09/2006 (planned) Complete W-band receiver construction 09/2006 Project on hold Begin CCB production science use 10/2006 12/2005 (see note)

Note: The Ka-band (26–40 GHz) and Q-band (40–48 GHz) receivers were installed on schedule. Early commissioning tests in fall 2005 demonstrated that the spectral baseline performance of the receivers was not acceptable for wide-line work. Accordingly, the Q-band receiver was released for narrow-line work only, and the Ka-band receiver for continuum work with the CCB (hence the early start date for CCB production science). The receiver baseline performance is currently under investigation, and the receivers will be re-installed in fall 2006.

Objectives and Schedule for FY 2007

During FY 2007, we will maintain or focus on delivering excellent observing capabilities at frequencies up to 50 GHz. Our key goals for this period are as follows:

• Successful completion of the azimuth track refurbishment project.

• Completion of the 25–50 GHz instrumentation upgrades, delivering as close as practical to theoretical performance from the Ka and Q-band receivers, coupled with the CCB and Zpectrometer backends.

Program Plan FY 2007 F. Telescope Science Operations 52

• Engineering commissioning and early science operations with the Penn Array.

• Significantly improved dynamic scheduling.

• Sufficient PTCS development work to support the above goals.

A more detailed breakdown, with intermediate milestones is given in Table F.2.2.

Table F.2.2. Milestones for FY 2007 Item Delivery Date Azimuth Track Refurbishment Work plan and schedule complete 10/2006 First 24 wear and base plates manufactured 01/2007 Next 24 wear and base plates manufactured 04/2007 Refurbishment starts 04/2007 Refurbishment complete 08/2007 Telescope performance restored 08/2007 Zpectrometer Lab tests complete 10/2006 Functional tests complete 11/2006 Science validation complete 05/2007 Penn Array Engineering tests complete 12/2006 Science validation complete 05/2007 Dynamic Scheduling Test phase plan in place 12/2006 Test phase complete 05/2007 Full proposal complete 09/2007 Precision Telescope Control System Trajectory Generation and Servo Improvements complete 12/2006 PLC interlock system installed 08/2007 Small-scale surface errors characterized 08/2007 Laser rangefinder V2 development complete 09/2007

Program Plan FY 2007 F. Telescope Science Operations 53

3. Very Large Array (VLA)

Accomplishments in FY 2006

Observing and User Programs

For a number of years the amount of scientific observing time used on the VLA remained very stable at 76–77% of the total number of hours, and the amount of lost time was fairly constant at 4% of scheduled antenna-hours. During FY 2006 the amount of scientific observing was reduced to about 70% in order to accommodate additional EVLA testing. As many as five antennas were out of the 27-antenna observing array for EVLA retrofits, but four EVLA antennas were returned to the default observing array in August 2006.

Two VLA Large Programs were completed in FY 2006: the VLA Low-frequency Sky Survey and a study of radio afterglows from gamma-ray bursts discovered by the Swift satellite. A new large VLA proposal to study high-mass star formation was approved in conjunction with a Spitzer Legacy program and started observations using the B configuration in mid–2006. A special proposal call was made for extragalactic “blank field” observations associated with deep surveys by other telescopes; four such programs, ranging from 60 to 90 hours of total observing time, were allocated time and observed during the past year.

The 10th Synthesis Imaging Summer School was held in June 2006 at the University of New Mexico and at the NRAO. It was the largest yet, with approximately 170 attendees at the 8-day school.

A new VLA Proposal Submission Tool debuted for the February 2006 proposal deadline and was required at the June 2006 proposal deadline. This tool is in common with the GBT and is ultimately expected to include VLBA capability as well.

EVLA Transition

During FY 2006 transition observing using EVLA antennas together with VLA antennas and the old correlator was debugged. In August 2006, four EVLA antennas will be returned to the operational VLA for all users, and one more antenna will be returned in September. Several of these antennas were used by the NRAO staff and experienced users before August, but their return on a routine basis was delayed so we could understand and reduce the interoperability problems of EVLA antennas with the VLA. The NRAO has compiled a detailed set of information that observers need to use the EVLA antennas together with the VLA; this list is supplied on the World Wide Web and updated approximately weekly. In addition, the NRAO began preparing a forecast of short-, medium-, and long-term predictions of VLA capabilities during the transition to EVLA. This forecast is e-mailed to a large list of individuals who have written VLA proposals in the past, approximately two weeks prior to each proposal deadline.

A first draft of a comprehensive EVLA Operations Plan for 2012 was completed and distributed for review. This plan provides the scientific and budget requirements for baseline EVLA Operations and for a new Array Science Center for the EVLA and VLBA. The draft plan also is the basis for generating a staffing plan for EVLA/VLBA Operations between 2007 and 2012.

Program Plan FY 2007 F. Telescope Science Operations 54

VLA + Pie Town Link

The fiber-optic link between the Pie Town VLBA antenna and the VLA was offered to observers once again in FY 2006. This link doubles the longest baseline of the VLA, improving the angular resolution by a factor of two for complete syntheses of northern sources and somewhat less for shorter observations or sources at low declinations. During the A-configuration period from February 2006 through May 2006, a total of 23 observing programs used the Pie Town link in 31 sessions for a total of 240 hours of observing, nearly 15 percent of the total A-configuration scientific observing time.

Dynamic Scheduling

During the antenna reconfigurations in fall 2005 and winter 2006, the VLA was primarily scheduled dynamically, with progressively more refined combinations of VLA and EVLA software. Beginning in May 2006, all “filler” VLA time was scheduled dynamically. The primary purpose of this dynamic scheduling at present is heuristic; unsurprisingly, we have learned that it is much easier to schedule short scheduling blocks (a few hours) than long blocks (10 hours or more). We will continue to adjust parameters of the dynamic scheduling as we learn to do this in a more automated fashion.

190 MHz System Installation

Scientists from the Smithsonian Astrophysical Observatory (SAO) and the NRAO proposed at the end of FY 2004 to install 190 MHz observing systems on the VLA in order to search for redshifted neutral- hydrogen emission from the epoch of reionization at redshift z ~ 6. Because of engineering problems and interference from television stations, the systems were not ready for use during the D configuration in October–December 2005. Following additional discussions and subsequent to NSF funding of the demonstration segment of the Mileura Widefield Array in Australia, this program was ended by the SAO.

Infrastructure

The degenerated azimuth bearing on antenna 26 was replaced by a new bearing in FY 2006, the 11th such bearing replacement done on the VLA. Railroad tie replacement has slowed in recent years to fewer than 3,500 ties per year, limited by the amount of materials and personnel available, as well as by an increased concentration on the repair of track intersections. In late FY 2006 significant track repairs also are being done to repair damage suffered during the summer monsoon season (see Figure F.3.1).

The standard Astronomical Image Processing System (AIPS) used for both the VLA and VLBA continues to be supported by the NRAO for export to its entire user community; a frozen 31DEC05 version of AIPS and a daily-updated 31DEC06 version were produced.

The VLA was the last remaining NRAO VLBI telescope recording data with the old longitudinal tape transports; a new Mark 5 disk-based recorder was installed at the end of FY 2006 to replace the tape recorder.

Program Plan FY 2007 F. Telescope Science Operations 55

Figure F.3.1. Two views of a partial washout of the VLA railroad tracks on the west arm, during summer thunderstorms on July 8 and 9, 2006. The left panel shows a view from below the tracks; all the “gravel” in the foreground is actually many tons of railroad ballast material washed out from beneath the ties. The right panel is a longitudinal view of the railroad tracks in the same location, with daylight showing beneath the ties and all the ballast carried downstream by runoff.

VLA Data Archive

A pilot project to produce images of all 5 GHz and 8.4 GHz archive data from a single VLA B configuration continued and is scheduled for completion in late FY 2006. At that time, responsibility for the project will be transferred to the NRAO e2e Operations Division.

VLA Milestones from the FY 2006 Program Plan

Table F.3.1 reproduces the list of major FY 2006 milestones for the VLA, as given in the 2006 NRAO Program Plan, together with the performance on those milestones.

Table F.3.1. Performance on VLA Milestones from 2006 Program Plan Item Planned Accomplished

Freeze AIPS version 31DEC05, begin 31DEC06 12/2005 12/2005 Release the new VLA proposal tool 12/2005 1/2006 Initiate the next Pie Town link observations 2/2006 2/2006 3/2006 (on request) Return the first EVLA antennas to the VLA 1/2006 8/2006 (default) Replace one azimuth bearing 9/2006 5/2006 Initiate operational dynamic scheduling 12/2007 5/2006 (filler time) Complete the archive imaging pilot project 1/2006 Early FY 2007 Replace 3,500 railroad ties 9/2006 Only ~3,000 done Decommission the Modcomp computers 7/2006 Moved to FY 2007

Program Plan FY 2007 F. Telescope Science Operations 56

Plans for FY 2007

Observing and User Programs

Significant changes are afoot for the VLA in FY 2007. Test time for the EVLA will continue to increase and will include tests of a small 4-station prototype of the EVLA correlator beginning in early FY 2008. A VLA/VLBA Large Proposal deadline is scheduled for October 2006, and the NRAO expects to award more than its previous average of 10% to 15% of all observing time to large proposals. In addition, we will begin adjusting the VLA configuration schedule in order to be prepared for the first tests with the EVLA production correlator in 2009; it is highly desirable for the VLA to be in its most compact configuration (the D configuration) for these first tests. From October 2006 through September 2007 we expect to stick with the traditional reconfiguration schedule, using the C, D, and A configurations along with their associated hybrid configurations. However, depending on large proposal pressure, the A configuration may be extended well beyond its normal 4-month length and could continue until the end of Calendar Year 2007.

The new VLA Proposal Submission Tool has been modified further for the October 2006 proposal deadline; changes then are expected to taper off as this Tool moves toward a maintenance and operations mode.

EVLA Transition

FY 2007 will be a critical year for the EVLA Project as it moves the last set of EVLA electronic components into full production mode. This means that the number of completed EVLA antennas will increase significantly, from 5 at the end of FY 2006 to 11 or 12 at the end of FY 2007. Although many EVLA capabilities will be available only after the production correlator arrives, there still will be a significant increase in the tuning capability in several EVLA bands, particularly C band (covering 4 to 8 GHz instead of 4.5 to 5 GHz) and K band (covering 18 to 26.5 GHz instead of 24 to 25 GHz). This enhanced frequency coverage will constitute the first new scientific capability made available by the EVLA, permitting observations (for example) of the 6.7 GHz methanol line and extragalactic water masers at z ~ 0.1.

More detailed EVLA transition planning will take place in FY 2007 in conjunction with a new EVLA Science Advisory Committee that will be formed. This planning includes a definition of the first EVLA observing modes that will be enabled, together with the requirements (software, hardware, and operational) to make those modes available to the outside user community.

The venerable Modcomp control computers for the VLA were not decommissioned as planned during FY 2006 because of the competition for limited software-personnel resources for the EVLA. Instead, this decommissioning will occur in FY 2007, before the arrival of the EVLA prototype correlator. Replacement of the old hardware and software will result in control of the VLA by an interim version of the EVLA control software, with provisions made to operate both the old VLA antennas and the new EVLA antennas with the old VLA correlator.

VLA + Pie Town Link

The VLA + Pie Town link will not be offered as a user capability during the A configuration in FY 2007 because of EVLA priority for electronics personnel, software personnel for EVLA control-system development, and for scientific staff for EVLA testing and commissioning.

Program Plan FY 2007 F. Telescope Science Operations 57

Dynamic Scheduling

In FY 2007 an increasing fraction of VLA time will be allocated via dynamic scheduling. It is a goal to implement this increased dynamic scheduling during the bad-weather summer months of 2007. As with some other operational capabilities, this may give way because of the higher priority for development and testing of critical EVLA software.

Infrastructure

Funding was allocated in FY 2006 for the refurbishment of three previously removed antenna azimuth bearings. Because of the personnel resources required for mechanical retrofits of EVLA antennas, no more than one bearing will be replaced in FY 2007.

The VLA antennas require improvements to their Antenna Control Units (ACUs) in order to meet the demanding EVLA specification of 6 arcsecond blind-pointing accuracy. A first step will be replacing the old analog tachometers with new digital tachometers; a similar upgrade has taken place on the VLBA over the last several years. During FY 2007 we expect to purchase digital tachometers for 10 of the 28 VLA antennas and complete the design of a new prototype ACU. We will replace the old analog tachometers as they show signs of failure or as the replacement fits in with the EVLA antenna retrofits, and we expect to install about five of the new tachometers on antennas in FY 2007.

In FY 2006, we purchased $200K in railroad materials. Together with these purchases, the track maintenance crew is returning to its full staffing of six individuals after being cut back by one person in an attempt to reduce operational spending. Therefore we expect the replacement rate of railroad ties to increase to above 4,000 per year for Calendar Year 2007.

A frozen 31DEC06 release of the AIPS software will be made, and the daily-updated 31DEC07 version will be initiated.

Since the EVLA will be a forefront scientific instrument through 2025 or 2030, attention must continue to be paid to long-term infrastructure maintenance. There are a number of important infrastructure projects: the acquisition and operation of a wider-bandwidth communication line from the VLA to the Array Operations Center (AOC), an upgrade of the VLA Atmospheric Phase Interferometer, achievement of the recommended long-term replacement rate of 5000 railroad ties per year, and initiation of a long-term program for replacing the vehicles at the VLA site. Costs of these items range from $50K to $130K each in FY 2007.

VLA Deliverables in FY 2007

Table F.3.2 summarizes key VLA deliverables for FY 2007. Since funding in the baseline budget permits very little new development beyond the EVLA project, almost all these deliverables are in the areas of continued operations and infrastructure maintenance. Specific EVLA deliverables may be found in the EVLA section of this Program Plan.

Program Plan FY 2007 F. Telescope Science Operations 58

Table F.3.2. VLA Milestones with Baseline Budget Item Delivery Date

Return the 6th EVLA antenna to VLA 10/2006

Freeze AIPS version 31DEC06, begin 31DEC07 12/2006

Complete the new VLA ACU prototype 3/2007

Offer the new frequency coverage of EVLA antennas 6/2007

Obtain 3 refurbished azimuth bearings for stock 6/2007

Decommission the Modcomp computers 6/2007

Return the 11th EVLA antenna to VLA 8/2007 Replace 4,000 railroad ties 9/2007

Install ~5 digital tachometers on VLA antennas 9/2007

Table F.3.3 provides a prioritized list of additional capabilities for the VLA and their estimated costs in FY 2007 dollars.

Table F.3.3. Prioritized additional VLA capabilities in FY 2007 and beyond Item Cost

Acquire a 150 Mbps link from the VLA to the AOC $100K +$60K/yr

Initiate the VLA student-grants program $100K

Carry out Phase II of the WVR project $120K

Increase the tie replacement rate to 5,000/yr $100K/yr

Initiate long-term VLA vehicle plan $100K/yr

Upgrade the VLA Atmospheric Phase Interferometer $50K

Digitize the fiber link from Pie Town to the VLA $130K

Program Plan FY 2007 F. Telescope Science Operations 59

4. Very Long Baseline Array

Accomplishments in FY 2006

Observing and User Programs

The VLBA continued to perform scientific observing for about 50% of the wall-clock hours in FY 2006, or 65% if scaled to the sustainable data rate of 128 Mbps. This observing rate is likely to remain fairly steady in the future. Although the Mark 5 recording systems would theoretically permit us to observe a larger fraction of the time, we are likely to “spend” any extra recording capability by doing more observing at 256 Mbps and 512 Mbps. The higher instantaneous sensitivity associated with these higher data rates enables better phase referencing through the use of more nearby, weaker calibrators, when compared to observing for a longer time at 128 Mbps.

The observations for three large VLBA programs began in late FY 2005 and early FY 2006 and continued throughout the fiscal year: long-term monitoring of the structures of active galaxies at 15 GHz, 5 GHz VLBA Imaging Polarimetry Survey (VIPS) of 1000 blazars that are likely to be gamma-ray sources detected by GLAST after its launch in late 2007, and an astrometric investigation of the spiral structure and kinematics of the Milky Way galaxy. Observations for the VIPS program were completed late in FY 2006.

Mark 5 Recording System

VLBI observatories around the world have moved rapidly away from tape-based and towards disk-based recording systems (Mark 5). Since the VLBA is the world’s only full-time VLBI imaging array, the cost of the VLBA conversion is more heavily weighted toward the cost of disk media, and less heavily toward the cost of recording/playback systems, than other observatories. For this reason, the NRAO delayed the full conversion until disk prices reached an affordable level for a large-scale operation. By early in FY 2006, all 10 VLBA stations and the GBT were equipped with Mark 5 recording systems, and the VLBA correlator had 11 playback units, but some tape-recorded observations were still made because of an insufficient supply of disks to use the Mark 5 units full time. However, by spring 2006, the VLBA had completely converted to Mark 5 except for global observations that required more than 11 inputs to the correlator. At the end of FY 2006, the VLA was converted to Mark 5 recording, and the number of correlator inputs was raised to 14 Mark 5 units in order to input the High Sensitivity Array (HAS = VLBA, VLA, GBT, Arecibo, and Effelsberg) on disk.

International VLBI

The VLBA continues to participate in a number of fixed VLBI sessions together with the European VLBI Network and/or other non-NRAO telescopes. In FY 2006 the VLBA took part in three global runs of the worldwide centimeter-wavelength VLBI network and two global λ = 3 mm VLBI sessions. These fixed sessions defeat the advantages of dynamic scheduling on the VLBA alone but provide additional scientific capabilities by providing significantly more collecting area and improved imaging capabilities. Since many of the users of the VLBA (and the VLA) are from non-U.S. institutions, we have begun discussions with our international partners about how we might increase the international participation in funding and governance of the VLBA in order to maintain and enhance its scientific capabilities.

Program Plan FY 2007 F. Telescope Science Operations 60

Astrometry

In FY 2006 the VLBA continued its bimonthly participation in geodetic/astrometric observations to improve the accuracy of the fundamental astronomical reference frame and to determine the Earth- orientation parameters. The VLBA often is used with other non-NRAO telescopes to place all VLBI antennas on a common geodetic frame, and it provides the strongest data in the long-running studies of such fundamental issues such as continental drift and nutation of the Earth.

The relative position accuracy of radio sources has reached the 10 microarcsecond level in a number of VLBA experiments. This precision is obtained thanks to the high stability of the VLBA system, the improved signal-to-noise resulting from increased bandwidth, and the availability of thousands of position calibration sources well distributed over the sky. Comparable astrometric precision will not be reached in the optical domain until the space-based astrometric observatory GAIA is launched in about 2012. The further increased sensitivity of the VLBA, discussed in the long range plan, will more than triple the number of detected radio stars and enable more studies of galactic dynamics with the VLBA.

Phase referencing, which is needed for astrometric observations and for detecting weak radio sources, is now used for more than half of all VLBA experiments. In FY 2006 phase-referencing observing strategies were developed to decrease the systematic phase errors that are often the main limitation to astrometric accuracy and image quality. In order to provide the VLBA astrometric capabilities to the larger astronomical community, the AIPS software system now includes updated astrometric corrections, pipeline and semiautomatic data-reduction processes, and a variety of astrometric programs for correcting ionospheric and tropospheric refraction.

Infrastructure

A program was started in the first quarter of FY 2004 to replace the expensive high-maintenance analog tachometers with low-noise digital tachometers. This was completed in July 2006 with installation of digital tachometers on the Mauna Kea VLBA station.

During early 2005 it became apparent that the St. Croix, VI VLBA antenna was suffering from severe rust damage due to the humid salt air at this seaside site, and a 3-week maintenance visit to St. Croix repaired the worst rust damage. In FY 2006 an NRAO mechanical engineer visited St. Croix and found the antenna to be structurally sound, but substantial additional rustproofing measures (including repainting the entire antenna structure) will be needed to maintain the long-term viability of the St. Croix antenna. The mechanical engineer reported (VLBA Antenna Memo No. 62) that, without a substantial program of corrosion control, “the St. Croix antenna structure would suffer a critical failure due to corrosion in less than 5 years.”

Standard VLBA tiger-team visits were made to the Kitt Peak, Mauna Kea, and Hancock VLBA antennas during FY 2006. These visits typically involve teams of 6–8 individuals who spend 1–2 weeks on intensive maintenance overhauls of the antenna systems. The three stations generally were found to be in good shape, although the antenna in Hancock, NH also shows signs of long-term deterioration due to the weather and needs repainting.

Late in FY 2005 we discovered that the VLBA correlator had not been using the most accurate values for Earth Orientation parameters (EOPs) determined after the observations took place, leading to a clearer understanding that the move toward more rapid correlation enabled by Mark 5 systems, and ultimately by eVLBI, potentially leads to inaccurate geometric models even if the best EOP values known are used at the time of correlation. Therefore, an AIPS task was modified, and an associated procedure written, to

Program Plan FY 2007 F. Telescope Science Operations 61

automatically access and apply more accurate EOP values at the time the data are analyzed. This enables improved phase referencing and astrometry for many VLBA observations.

Since its inception, cooling of the VLBA correlator has relied on air-conditioning units that were original equipment at the VLA site in the late 1970s. These units have reached the end of their operational lives and can no longer be maintained. New air conditioning units were installed in FY 2006 in order to keep the correlator operational.

VLBA Data Archive

By the end of FY 2006, all VLBA archive data from late 1998 through the most recent data correlations will be loaded into the on-line VLBA archive.

Performance on VLBA Milestones from the FY 2006 Program Plan

Table F.4.1 lists the VLBA milestones from the FY 2006 Program Plan and the performance on those milestones.

Table F.4.1. VLBA Milestones from the FY 2006 Program Plan Item Predicted Accomplished Eight full-time Mark 5 stations 10/2005 12/2005 Ten full-time Mark 5 stations 6/2006 6/2006 Completion of the digital-tachometer conversion 6/2006 7/2006 Paint the St. Croix antenna 6/2006 Deferred to 2007 Observing increase to 58% of hours in year 9/2006 Data rate increased instead Maintenance visits to HN, MK, and SC 9/2006 Visited KP, MK, and HN; evaluation visit to SC

Plans for FY 2007

Observing and User Programs

We expect to eliminate all tape-recording systems from the VLBA in FY 2007. This will increase the amount of observing time available at data rates of 256 Mbps and 512 Mbps.

The new NRAO Proposal Submission Tool may be extended in FY 2007 in order to include the VLBA, depending on competition for software resources with higher priority EVLA deliverables.

The three large VLBA programs under way during FY 2006 are all scheduled to conclude in FY 2007. A new large-proposal deadline will occur in October 2006, and the NRAO has announced that a larger fraction of observing time than the previously typical ~15% will be allocated to large proposals if scientifically warranted.

We are actively engaged in making it easier for non-experts to use the VLBA. In FY 2007 we expect to increase significantly the capabilities for automated scheduling of the VLBA; an early version of this automated scheduling was used successfully in the VIPS Large Program in FY 2006. In addition to the automated scheduling, improved data pipelines and/or the NRAO staff assistance should lead to the production of reference images for a significant subset of VLBA imaging programs. Finally, we expect to initiate a VLBA student grants program, possibly associated with the VLBA large proposals.

Program Plan FY 2007 F. Telescope Science Operations 62

Mark 5 Recording System

In FY 2007 we expect to acquire several more Mark 5 playback units so that we have 17 on the VLBA correlator. The VLBA correlator can accept input data streams from a maximum of 20 stations. However, since only a few geodetic and global VLBI observations use more than 17 observing stations, our plan is to stop at 17 or 18 Mark 5 playback units. Any additional Mark 5 funds will be spent on increasing the pool of disk modules or on enhancements of the Mark 5A system to the Mark 5B system. The Mark 5B system, which records and reproduces “format-free” data, will be necessary to enable 1024 Mbps recording on the VLBA.

International VLBI

The VLBA will continue to participate in Global centimeter- and millimeter-wavelength VLBI sessions during FY 2007 as well as being the anchoring set of antennas for the High Sensitivity Array. We expect to continue exploring the possibility of establishing a more formal International VLBI Network, with a goal of having a more detailed description of this network and formal letters of agreement among its partners.

Infrastructure

Tiger-team maintenance visits will be made to Fort Davis, Owens Valley, and Brewster in FY 2007. An analysis in FY 2006 showed that St. Croix is in serious need of corrosion repair and rustproofing, including repainting of the entire antenna structure. The cost estimate for a long-life antenna repair is $200K plus 12 weeks of downtime for the antenna. In FY 2007 we must decide whether to go forward with this long-term repair of St. Croix or a more modest effort of about $40K/yr that will stabilize the antenna for the next few years. In addition to the general rustproofing effort at St. Croix, it is highly desirable to replace the present subreflector, which is seriously corroded. Doing so would require reworking the misshapen subreflector removed from Brewster in 2004 so that it could be installed at St. Croix. Although highly desirable, this subreflector rework is dependent on the availability of sufficient personnel resources in the antenna-mechanic group and has a lower priority than EVLA antenna retrofits.

Since 2001 the VLBA has been without a dedicated software engineer for maintenance and enhancement of operational VLBA software because almost all available software resources have been diverted to the EVLA. VLBA operational software includes VLBA station software, real-time correlator software, maintenance and enhancement of many data bases used by the array and the correlator (e.g., station and source locations, Earth orientation data bases), and software for interfacing recording systems to the correlator. Reliance on astronomers and EVLA software engineers who spend only a small amount of time on the VLBA is now insufficient for routine operations and maintenance. The advent of Mark 5 recording systems requires considerable additions to station and correlator software, and it also raises the prospect of operational savings by using unattended correlation if enabled by the addition of some new software tools. Therefore in FY 2007 we plan to hire a dedicated VLBA software engineer on the operations budget. This individual will take over the support of ongoing operations software, further develop Mark 5 and correlator software, and take over primary responsibility for long-term software developments related to data recording, data correlation, and eVLBI.

VLBA Data Archive

In FY 2007 we will continue to load VLBA data into the on-line data archive. We anticipate that the on- line archive will reach back as far as 1995 or 1996 by the end of FY 2007. The archive presently includes a significant amount of calibrated data and images from a few special-purpose survey programs.

Program Plan FY 2007 F. Telescope Science Operations 63

Additional images may be loaded in FY 2007 as operation of a VLBA data pipeline becomes more routine.

VLBA Deliverables in FY 2007

The table below summarizes those major VLBA technical-development milestones for FY 2007 that are possible within the baseline budget.

Table F.4.2. VLBA Development Milestones in FY 2007 with Baseline Budget Item Delivery Date

Publish a plan and budget for the VLBA to reach 4 Gbps in 2011 04/2007 Install interim FRM replacements at PT and HN 09/2007 Prototype a new VLBA FRM system 09/2007 Upgrade two Mark 5A recorders to Mark 5B 09/2007

Below is a prioritized list of additional technical development capabilities for the VLBA that are desirable for FY 2007 plus their estimated costs in FY 2007 dollars:

• Begin 22 GHz receiver upgrade, $100k • Begin 43 GHz receiver upgrade, $100k • Convert 10 Mark 5A recorders to Mark 5B, $60k

Table F.4.3 summarizes key VLBA science-operations deliverables in FY 2007.

Table F.4.3. VLBA Science Operations Milestones in FY 2007 with Baseline Budget Item Delivery Date

Conversion of the HSA to Mark 5 10/2006 Correlator achieves 17 Mark 5 inputs; last tape drives discarded 12/2006 First observations for new VLBA large proposals 01/2007 Initial VLBA student observing grants awarded 01/2007 St. Croix rustproofing project begins 05/2007 Maintenance visits to Fort Davis, Owens Valley, and Brewster 09/2007 Completion of the two remaining large proposals from FY 09/2007 2005/06

Below is a prioritized list of additional operational capabilities for the VLBA that are desirable for FY 2007, plus their estimated costs in FY 2007 dollars.

• Major rustproofing for St. Croix, $200k • Resurface the Brewster subreflector and install it at SC, $50k • Construct a spare λ = 3mm receiver, $50k • Repair the third spare VLBA maser, $45k

Program Plan FY 2007 F. Telescope Science Operations 64

G. Technical Capability Development

1. Central Development Laboratory Summary

The Central Development Laboratory designs, develops, fabricates, and supplies unique components, in particular low-noise amplifiers, MMIC circuits, cryogenic mixers, passive electromagnetic components, digital data-processing systems, and specialized receivers for other NRAO facilities (ALMA, the VLA, VLBA, GBT and EVLA) as well as other projects and activities, such as FASR and WMAP, for the astronomy community.

Table G.1.1 FY 2007 Projects and Activities CDL Projects FY 2007 Summary Keep pace with EVLA receiver needs Refine the designs for 18–26 and 26–40 GHz Low-noise cryogenic HFET and Demonstrate state-of-the-art performance in ALMA bands 1 advanced amplifiers and 2 Study the cryogenic noise properties of Heterostructure Bipolar Transistors (HBTs) Design new GaAs power amplifiers for ALMA Band 3 and Band 7 Design decade-bandwidth dual-channel downconverter MMIC development Design a differential low-noise active balun Evaluate MMIC voltage-controlled oscillators both on-wafer and in-package Measure 385–500 GHz Nb SIS mixer Millimeter- and Submillimeter-wave Evaluate diffusion-cooled Hot Electron Bolometer mixer mixers Evaluate NbTiN SIS mixers Develop balanced SIS mixers Develop a 300/800 MHz prime-focus feed for the GBT Electromagnetics Measure the 79/104 GHz ALMA holography feeds Build and measure full-size EVLA 2–4 GHz feed Develop a phase shifter for the 84–106 GHz band Complete the Green Bank Solar-Radio-Burst Spectrometer (GB/SRBS) and transition to full operations Solar Radio Burst Spectrometer Continue data archive in Charlottesville Continue R&D for FASR solar telescope array Construct a sixteen-element array at Mileura Station Precision Array to Probe the Epoch of Increase the collecting area of the sleeved dipoles Reionization (PAPER) Expand the correlator to handle 32 dual-polarized elements

Program Plan FY 2007 G. Technical Capability Development 65

Cryogenic HFET Development

The NRAO is the recognized leader of cooled HFET (Heterostructure Field-Effect Transistor, sometimes called HEMT) amplifier design and construction for radio-astronomy use. The NRAO has produced hundreds of HFET amplifiers for use on the NRAO telescopes and for others in the radio-astronomy community and other research areas. These range from low-frequency amplifiers (for <1 GHz) used in fundamental particle physics and magnetic-resonance imaging development to the highest attainable frequencies for cosmic microwave background experiments.

Accomplishments in FY 2006

Amplifier Development

The development of new amplifier designs for 4–8, 4–12, 12–18 and 40–50 GHz for the EVLA had been completed (Figure G.1–4). A collaborative effort with the Center for Astrophysics (CfA) on mm-wave SIS mixers with extremely wide IF bandwidths required development of yet another version of this amplifier covering 5–20 GHz (Figure G.5).

(a) (b) Figure G.1.1. (a) 4–8 GHz amplifier with lid removed. (b) Noise and gain performance of the 4–8 GHz amplifier.

Program Plan FY 2007 G. Technical Capability Development 66

Gain and Noise of 4_12 GHz Amplifiers at 15 K 20 40 X03 Noise (L) X13 Gain (R)

X03 Gain (R) X24 Noise (L) 15 30

X11 Noise (L) X24 Gain (R) 10 20

X11 Gain (R) X29 Noise (L) (dB) Gain

5 10 X13 Noise (L) X29 Gain (R) NoiseTemperature (K)

0 0 3000000000 5000000000 7000000000 9000000000 11000000000 13000000000 Frequency (Hz)

Figure G.1.2. Gain and noise temperature measured at 15 K of several 4–12 GHz amplifiers using a cryo3 4200 TRW device in the first two stages and an HRL device in the third stage.

Noise and Gain of 8-18 GHz Amplifiers at 15 K 20 40

PlotCol(1,2) (L) U21noise 15 30 PlotCol(1,3) (R) U21noise PlotCol(1,2) (L) 10 20 U18noise Gain (dB) PlotCol(1,3) (R) U18noise 5 10 Noise Temperature (K)

0 0 8000000000 11000000000 14000000000 17000000000 20000000000 Frequency (Hz)

Figure G.1.3. Gain and noise temperature measured at 14 K of two 8–18 GHz amplifiers using a cryo3 4200 TRW device in the first two stages and an HRL device in the third stage.

Program Plan FY 2007 G. Technical Capability Development 67

Figure G.1.4. The 8–18 GHz amplifier with the lid (shown at right) removed.

NOISE AND GAIN OF 5-20 GHz AMPLIFIERS AT 14 K 20 40

15 30

10 20 Noise Noise

5 10 Gain (dB)

Temperature (K) (K) Temperature 0 0 4 6 8 10 12 14 16 18 20 Frequency (GHz)

u46 Noise u47 Noise u46 Gain u47 Gain

Figure G.1.5. Gain and noise temperature measured at 14 K of two 5–20 GHz amplifiers using a cryo3 4200 TRW device in the first two stages and an HRL device in the third stage.

A redesign of the 35–46 GHz amplifier developed originally for WMAP to achieve flat noise and gain over the 40–50 GHz EVLA frequency band has been successfully completed (Figure G.6).

Program Plan FY 2007 G. Technical Capability Development 68

Measured and Modeled Gain and Noise of Q Band Amplifier at 20 K 40 40

Gain Mod. (R) 30 30

Noise Mod. (L) 20 20

Noise Meas. (L) Gain (dB)

10 10 Gain Meas. (R) TemperatureNoise (K)

0 0 30000000000 35000000000 40000000000 45000000000 50000000000 Frequency (Hz)

Figure G.1.6. Measured and modeled gain and noise temperature at 20 K of the 40–50 GHz amplifier using a cryo3 2060 NGST device in the first stage and HRL devices in subsequent stages.

Production amplifiers were built for receiver systems on the GBT and EVLA. The total number of new amplifiers produced in the last year was 50, of which 32 were delivered to the EVLA. In addition, work has been carried out to repair and perform Cryo-3 upgrades to 25 additional LNAs.

Amplifier Research

Progress in SiGe and InP heterostructure bipolar transistors (HBTs) has made their application in radio- astronomy receivers feasible at frequencies up to 115 GHz. Although these devices are not expected to offer the noise performance of InP HFETs, especially at cryogenic temperatures, they could in principle offer an order-of-magnitude lower 1/f-like gain fluctuations, which currently set the minimum switching frequency of broadband continuum receivers, thus improving radiometer sensitivity and perhaps lowering cost. Research into noise models of HBTs applicable at cryogenic temperatures has started, and a paper study of their noise properties has been published.

Planned Activities for FY 2007

The designs of amplifiers for the 18–26 GHz and 26–40 GHz EVLA bands will be refined to improve gain flatness at the band edges. Also, cryogenic InP HFET amplifiers demonstrating state-of-the-art performance in ALMA bands 1 and 2 will be demonstrated. Further research into the cryogenic noise properties of HBTs and their possible applications in total-power radio-astronomy receivers is planned.

MMIC Development

The CDL continues development of a wide variety of custom centimeter- and millimeter-wave Monolithic Millimeter-Wave Integrated Circuit (MMIC) components. A MMIC-based approach for the front ends holds the promise of more compact, lightweight receivers and possible cost savings for large array receivers. This will have a positive impact on many fronts from cryogenics and power distribution to antenna structure and maintenance operations, as well as improved impedance match, gain slopes, and even optical parameters such as beam spacing and field of view.

Program Plan FY 2007 G. Technical Capability Development 69

Cost-effective progress in this area depends not only on taking full advantage of shared mask sets and collaboration with other research institutions, but also on keeping close track of commercially available MMIC product lines, which are growing rapidly. Even very sophisticated receivers can now be built using 90% commercial MMICs below 50 GHz, with some components available as high as 100 GHz. Our MMIC development is therefore centered on the unique elements that do not exist commercially, such as those that require unusually wide bandwidths, cryogenic operation, or non-standard port impedance.

The latest MMIC mixer and multiplier designs for the ALMA Active Multiplier Chain local oscillators have been completely successful, so recent efforts have focused on improving power output and reliability of the wideband power amplifiers. There is also new work being done in the area of decade- bandwidth-feed to low-noise-amplifier integration for the FASR and Square Kilometer Arrays, and for ultra-wideband downconversion of RF to IF signals.

Accomplishments in FY 2006

In FY 2006, new MMIC designs have included: 1. A revised version of the wideband MMIC LNA for the 11–34 GHz SKA band. 2. A new GaAs MMIC power amplifier (PA), fabricated at BAE Systems, that meets the requirements for ALMA Bands 4, 8, and 9 with better lifetime than previously existing PAs (see Figures G.1.7 and 8.)

Figure G.1.7. 65–85 GHz Medium Power Amplifier now in use for ALMA Bands 4, 8, and 9. The chips were fabricated at BAE Systems in their 0.1 µm Space-Qualified GaAs Power pHEMT MMIC process. Chip dimensions are 2.8 x 1.8 x 0.05 mm.

Program Plan FY 2007 G. Technical Capability Development 70

Figure G.1.8. Measured output power of a two-chip power-combiner module for ALMA Band 9 using the MMPA75 MMIC. The output power is sufficient to drive an X9 frequency multiplier.

In addition to these MMIC designs, a wide-bandwidth Voltage Controlled Oscillator (VCO) MMIC development effort has been carried out by a post-doctoral visiting researcher from the Institute of Astronomy and Astrophysics, Academia Sinica (ASIAA) under the guidance of CDL staff. This wide- bandwidth VCO MMIC, if successful, could be used to replace the YIG-tuned oscillators in future ALMA local oscillators. The MMIC VCO can be integrated in a single small package with the remainder of the LO driver components and requires much less DC power. Other potential applications include integrating MMIC VCOs, as local oscillators, in compact receiver elements for focal plane arrays. Four different MMIC VCOs have been designed and are currently being fabricated at a Taiwanese foundry.

Planned Activities for FY 2007

Plans for the immediate future include:

1. Develop and test GaAs power-amplifier design based on BAE system’s new 80 nm GaAs pHEMT technology (which should work at frequencies up to about 130 GHz) for ALMA Band 3 and Band 7 to improve lifetime. 2. In collaboration with JPL, revise the existing dual-channel 26–40 GHz MMIC downconverter design for the Deep Space Network Array to provide extended bandwidth. 3. In collaboration with UC Berkeley, develop a decade-bandwidth dual-channel downconverter for the Allen Telescope Array. 4. Develop a differential low-noise active balun (impedance transformer) for FASR, noise-matched to the log-periodic feed input impedance. 5. Evaluate MMIC VCOs both on-wafer and in-package.

Program Plan FY 2007 G. Technical Capability Development 71

Millimeter- and Submillimeter-Wave Receiver Development

In addition to the ALMA 211–275 GHz receiver work reported in the ALMA section, three millimeter and sub-millimeter technical development efforts are currently being carried out at the CDL (only one of which is funded by the NRAO): development of a new SIS mixer design for 385–500 GHz, development of a Hot Electron Bolometer (HEB) mixer for 600–720 GHz, and a new technology development effort for 350 µm (780–950 GHz) heterodyne receivers.

Accomplishments in FY 2006

385–500 GHz SIS mixer

The joint R&D project between the NRAO and the UVa for a new 385–500 GHz beam-lead SIS mixer, supported mainly by an NSF grant to the UVa, continued. The NRAO is providing mixer designs and the UVA foundry is fabricating devices. This work will explore the use of both Nb and NbTiN materials for sub-mm SIS mixers. Mixer design using beam-lead connections of the mixer chip to the external circuit is complete. Development of the junction fabrication process was carried out.

HEB mixers

This work began as a Small Grant for Exploratory Research from the NSF under the Approaches to Combat Terrorism program. Although the grant has ended, collaboration with the University of Virginia continues, supported partly through UVa’s NSF grant. The goal of this work in FY 2006 was to verify that the performance of the ultra-thin Silicon on Insulator (SOI) substrate beam-lead HEB mixers matches that of the existing state-of-the-art waveguide HEB mixers. Design and optimization of the next phase of 1.5 THz pHEB mixers on SOI can then proceed. Phonon-cooled (pHEB) mixers designed and built at the UVa have been successfully cryogenically tested at the CDL. An NSF REU summer student upgraded the test receiver to include a 3–13 GHz cryogenic LNA; the pHEB mixer was measured to have an IF bandwidth greater than 7 GHz, which is the widest IF bandwidth ever reported for this type of mixer.

350 µm (780–950 GHz) Heterodyne Receiver Technology Development

At present, no heterodyne receivers for the 350 µm atmospheric window can achieve the nearly quantum-limited sensitivity that niobium SIS receivers provide below ~600 GHz. Success in this work would enable the NRAO to provide the best possible receivers for ALMA Band 10 and provide bridging funds to continue mm-wave receiver development at the NRAO and the UVa until the start of ALMA operations. The goal is to produce reliable, repeatable, inexpensive, quantum-limited receivers using recently developed SIS mixer fabrication technology.

Our collaborators, the University of Virginia Microfabrication Laboratory (UVML), have successfully developed a process for producing high quality NbTiN films, a major step towards NbTiN SIS junctions. In addition, the first NbTiN trilayer structure (NbTiN/AlN/Nb) has now been made at the UVML. Figure G. 9 shows the sharp superconducting film transition at ~14 K.

Program Plan FY 2007 G. Technical Capability Development 72

Figure G.1.9. Resistance vs temperature plot for a NbTiN film [T. Cecil, MS Thesis, UVa, 2005].

Balanced SIS Mixer Development

Our work on balanced mixers is funded primarily by the Arizona Radio Observatory of the University of Arizona.

Balanced mixers have three desirable characteristics for radio astronomy receivers: (i) immunity to LO sideband noise, (ii) 50 times lower LO power requirement, and (iii) 3 dB greater dynamic range. A critical component of a balanced mixer is a 180-degree IF hybrid which separates the downconverted signal and downconverted LO sideband noise. We have designed and tested a superconducting 180- degree IF hybrid covering 4–12 GHz that is small enough to be mounted inside the mixer block. The hybrid was fabricated at the University of Virginia Microfabrication Laboratory and tested at the CDL (Figures G.1.10 and 11).

Figure G.1.10. The 4–12 GHz superconducting hybrid chip in a microstrip test fixture. The chip is 1.4 x 0.5 x 0.4 mm thick. Multiple bond wires are visible between the chip and the four microstrip lines and to ground.

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Figure G.1.11. Simulated (upper) and measured (lower) characteristics of the 4–12 GHz superconducting 180- degree hybrid. The upper (red) curves indicate the coupling (dB) from the mixer ports to the IF amplifier port when the signals at the mixers are out-of-phase (e.g., the downconverted signal from the sky in a balanced mixer), and the lower (green) curves show the same quantity when the signals at the mixers are in-phase (e.g., the downconverted LO sideband noise in a balanced mixer). Circuit loss is desired to be zero (red curve) and rejection of LO noise is desired to be large (green curve); both objectives are achieved.

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Planned Activities for FY 2007

385–500 GHz SIS mixer

We plan to continue the optimization of the junction fabrication process at the University of Virginia Microfabrication Laboratory, fabricate a wafer, design the mixer block, and evaluate the mixer performance.

HEB mixer

We will collaborate with Prof. Weikle of the UVa to measure the IF characteristics of a diffusion-cooled HEB (dHEB) mixer, which in theory should have a larger IF bandwidth than the pHEB mixer. A dHEB mixer is being built at the University of Virginia and will be measured and compared to the pHEB mixer already characterized.

HBT Development

We are collaborating with the University of Illinois (UI) in ultra-high-speed HBT development. The UI is part of a large group developing transistor components for 340 GHz systems. We have designed waveguide transitions that UI has integrated on their test MMICs so that they can be tested in-package at 170 and 340 GHz. The 170 GHz HBT power-amplifier MMIC is wideband and has potential applications to ALMA band 10. We will also acquire some single HBT test devices for room-temperature and cryogenic testing to develop noise models for HBTs as we have done for HFETs. Developing a good understanding of these devices may allow their use in broadband continuum radiometers where their expected much-lower 1/f noise could be a considerable advantage.

350 µm (780–950 GHz) Heterodyne Receiver Technology Development

This work will be supported jointly by the NRAO and the Arizona Radio Observatory of the University of Arizona. The mixers will use the Si membrane and beam-lead technology developed at the UVML and successfully used on our 600 GHz HEB mixers. They will be designed for a 4–12 GHz IF band, which is compatible with the ALMA IF system. Initially, balanced mixers will be used, but eventually we plan to use balanced sideband-separating mixers to obtain the benefits of both the balanced configuration and sideband separation. Development of the junction fabrication process is currently under way at the UVML. In FY 2007, the current NRAO SIS mixer test setup will be upgraded for this new frequency band. We expect to test the first basic double-sideband mixers in FY 2007, a necessary first step toward components useful on telescopes.

Balanced SIS Mixer Development

This work is primarily supported by the Arizona Radio Observatory of the University of Arizona. To verify the operation of a balanced mixer using the superconducting IF hybrid described above in conjunction with an SIS mixer, we are designing a balanced SIS mixer using the successful ALMA Band 6 mixer chip. When the NbTiN technology being developed at the UVML is ready, we will make balanced SIS mixers for operation in the 600–720 GHz and 780–950 GHz bands on the Arizona Radio Observatory Sub-Millimeter Telescope (SMT). The final phase will be to develop sideband-separating versions of these balanced mixers for the SMT and, eventually, ALMA.

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Electromagnetics

Thanks to recent advances in wide-band amplifiers and mixers, the bandwidth of many receiving systems is no longer limited by these active components, but by passive components such as feed, phase shifter, and orthomode transducer. We have designed and tested several new components with the goal of having receiver performance limited only by the bandwidths of single-mode waveguide at high frequencies and by feed dimensions at low frequencies.

Accomplishments in FY 2006

The holography receiver for measuring ALMA antennas will be used at 79 and 104 GHz. A scaled prototype of the holography feed was designed with a center frequency of 4.28 GHz (Figure G.1.12). This feed is designed to provide flatter amplitude and phase patterns than an earlier feed. The measured illumination taper at 62° is -5.5 dB and the 10 dB beamwidth is 156°.

A scaled version of the EVLA 4–8 GHz feed for 2–4 GHz would result in an aperture diameter of 44 inches for the 2–4 GHz feed, which would not fit in the available space. A new design with an aperture diameter of 42 inches was completed. A half-size prototype of this feed was fabricated and successfully tested.

The GBT beam at 1.4 GHz was calculated using the NEC-Reflector code (SatCom Workbench) developed at the Ohio State University.

A study of the beam-pattern properties of a prime-focus array receiver for the GBT at 1.4 GHz and 2.5 GHz was completed. For a 2.4λ feed offset, the gain loss of the telescope is about 1 dB. A feed array with one feed on-axis and six feeds in an outer ring is a possible configuration for a gain loss under 1 dB for the outer feeds. However, these feeds will have an illumination taper of −10 dB at the edge of the subreflector compared to the typical −12 dB taper as in a standard single-feed configuration. This means that each of the elements of the array receiver would have slightly more spillover noise than that of the single feed receiver, in addition to having slightly less gain.

Figure G.1.12. Prototype of ALMA Holography Feed – scaled to 4.28 GHz.

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Planned Activities for FY 2007

• Work will continue on the design and testing of a 12–18 GHz feed for the EVLA. Polarizers for the 8–12 and 12–18 GHz bands will be designed and tested. • Develop a dual frequency 300/800 MHz prime-focus feed for the GBT. • Develop a corrugated phase shifter for the 84–106 GHz band. • Build and measure a full-size EVLA 2–4 GHz feed. • Measure the 79 GHz and 104 GHz ALMA holography feeds.

Green Bank Solar Radio Burst Spectrometer (GB/SRBS)

In June 2003 the NRAO received a three-year NSF MRI grant to develop the Green Bank Solar Radio Burst Spectrometer (GB/SRBS), an instrument to receive solar radio emissions with adequate temporal and spectral resolution to probe a wide variety of active solar phenomena from the base of the corona. It consists of radio spectrometers to provide contiguous frequency coverage from 10 to 2500 MHz. It provides a basic research tool in solar radiophysics for use by the wider community, remedies the lack of an important component of the U.S. Space Weather effort, and provides a platform for research and development work on broadband antennas, feeds, and receivers needed for the upcoming Frequency Agile Solar Radiotelescope (FASR) project.

Accomplishments in FY 2006

Two systems covering the bands 20–70 MHz and 250–1000 MHz continue to operate on a daily basis with excellent reliability; the data are archived for public access. Over the past year, work has progressed toward meeting the October 2006 deadline for completing all of the instrument development tasks; routine operations will begin shortly thereafter. A dual-polarization wide-bandwidth antenna that covers 70–300 MHz has been designed and fabricated; a prototype digital spectrometer for 30–350 MHz has been completed. Work to install and upgrade all systems, including telescope and infrastructure improvements, will be completed in August 2006.

Graduate students continue to be an integral part of the instrument program. One student from the University of Virginia has developed a high-speed data-acquisition and analysis system that will use the GB/SRBS receiver on the 45-foot telescope to search for the very short duration (<10 nS) pulses of Cherenkov radiation emitted when a high-energy particle interacts with the lunar regolith. This work was partially supported by a grant from Sigma Xi.

Another graduate student from the University of Virginia is developing an improved wide-bandwidth sinuous feed that is highly integrated with a low-noise amplifier. This work will also have direct application to the proposed FASR array. A cryogenic version of the integrated front-end system is also being studied.

Planned Activities for FY 2007

The completed GB/SRBS will transition to full operations in early FY 2007. Data will continue to be archived in Charlottesville. Research to improve the bandwidth and noise performance of the feed/amplifier system will continue for application to FASR.

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Precision Array to Probe the Epoch of Reionization (PAPER)

At the end of the “Dark Ages” the first stars formed from the gravitational collapse of the densest regions of the primordial cosmic structure. Ultraviolet photons from these stars excited the hyperfine (spin-flip) transition in hydrogen and led to emission from the intergalactic medium in this spectral line, now greatly redshifted. The NRAO is assisting in the development of an instrument designed to search for this hydrogen signature of reionization. A team of researchers from U. C. Berkeley, the University of Virginia, and the NRAO is pursuing the design, fabrication, deployment, calibration, and operation of this unique imaging instrument. A prototype array is being developed for deployment in Green Bank, while a larger version is being planned for Western Australia.

Accomplishments in FY 2006

Three graduate students are actively involved in this work. The U.C. Berkeley researchers in conjunction with the Berkeley Wireless Research Center and the Center for Astronomical Signal Processing and Engineering Research developed an 8-channel full-Stokes correlator. The NRAO and University of Virginia researchers designed, fabricated, and characterized eight 120–200 MHz RF sub-systems. An effective, inexpensive shielded enclosure was developed for RFI prevention. In June 2006 the group successfully deployed an 8-element full-Stokes imaging array in Green Bank with a maximum baseline length of 300 meters.

We have also assisted our Australian colleagues in defining the infrastructure requirements for the Radio Astronomy Park currently being established at a site within Mileura Station. We have also participated in discussions regarding the legislation of a Radio Quiet Zone in Western Australia.

Planned Activities for FY 2007

The engineering of the RF sub-systems to improve manufacturability, reduce cost, and enhance reliability will be a priority as the number of array elements deployed in Green Bank increases to 32. A small NSF grant to the University of Virginia and U.C. Berkeley will support two graduate students and enable the construction of a small sixteen-element array at Mileura Station. Here, baseline lengths will be increased to a maximum of 600 meters.

Ways to increase the collecting area of the sleeved dipoles will also be explored. The correlator will be expanded to handle 32 dual-polarized elements. A unique system that makes use of the strong down-link signals from a constellation of low-Earth-orbit satellites will be developed to measure accurately the beam pattern of the array elements. This system will also have an impact on antenna designs for FASR, SKA, LWA, etc.

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H. New Initiatives

1. The Square Kilometer Array (SKA)

During the past year we have been leading the effort to develop the systems-engineering design for the SKA and to develop criteria for effective operation of the SKA. These activities will continue in 2007 along with further detailing of the scientific case. Priorities for the development of new technology, such as advanced imaging algorithms, new receiver designs, low cost antenna structures, long-distance data transmission, and RFI mitigation will be heavily weighted toward the needs of SKA. The overlap of development for our existing instruments (EVLA, GBT, and VLBA) and for the SKA presents the opportunity for considerable synergy. Wide-band and wide-field imaging is a challenge for the EVLA and SKA. Ionospheric correction algorithms are a crucial component of all low-frequency SKA concepts, including the LWA, and our experience with image processing at 74 MHz on the VLA will be extended to the new instruments. We have begun a collaboration with Berkeley to improve their ATA 0.5-11 GHz feed/LNA and to apply their design to a new pulsar receiver for the GBT. This feed/LNA design is a contender as the receiver for the LNSD SKA concept, but its noise temperature must be reduced by a factor of two. Joint development of data transmission technology for real-time VLBI is being pursued with the Haystack Observatory for possible VLBA upgrade and as a key element in an SKA design.

The U.S. SKA Consortium plans to submit a revised Technology Development Program (TDP) proposal to the NSF in the fall of 2006. The NRAO plans to provide the project manager for this program.

2. The Long Wavelength Array (LWA)

Scientists from the Southwest Consortium for radio astronomy plan to build an array of low-frequency radio antennas (20 to 88 MHz) spread over several hundred kilometers of southern New Mexico and West Texas. This Long Wavelength Array (LWA) would be used for low-frequency astronomy and ionospheric studies. The first phase of LWA, the Long Wavelength Development Array (LWDA) was funded previously, and involves the placement of a “station” consisting of a small number of dipole antennas on the VLA site. In FY 2006, 16 LWDA antennas were installed at the VLA site, with power and fiber optics connected.

The NRAO and the University of New Mexico (the “legal” partner of the Southwest Consortium) have a very general letter of understanding regarding support of the LWA, with any detailed cooperation to be spelled out by more specific contracts or memoranda. To date, the NRAO has agreed to host the LWDA, and has provided some infrastructure support to LWDA, with the full costs of NRAO activities being reimbursed by UNM. Some NRAO scientific staff members use their personal research time to participate in LWA science and engineering planning, and NRAO/UNM also collaborate in imaging algorithm development that is expected to be of use for both the LWA and the EVLA.

The University of New Mexico received funding for the next phase of LWA in the FY 2006 Department of Defense budget, but the actual dollars are not expected to arrive until the end of FY 2006. In FY 2007, the Southwest Consortium plans to build up a full LWDA test “station” on the VLA site and begin test observations. The NRAO again will support this construction effort on a full-cost-reimbursement basis. It is possible that tests will include an attempt to correlate the LWDA station against one or more VLA antennas; at this writing, it is more likely that this will occur in FY 2008.

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3. The Frequency Agile Solar Radio Telescope (FASR)

Progress on FASR design and development has been severely hampered by delays in receipt of NSF funds and their disbursement by the NRAO through subcontracts to partner institutions. No NRAO or AUI funding is anticipated in FY 2007, and anticipated funding from the NSF ATM Division is much less than needed meet previously planed targets. We will be re-evaluating the role of the NRAO and AUI in this important project which has been strongly endorsed by the solar-astronomy community.

4. Space VLBI

There appears little chance that the NRAO will have the resources to support the Russian RadioAstron mission which is currently planned for launch in 2008. Discussions with Japanese scientists will continue with the goal of defining the NRAO role in their 2011 or 2012 VSOP-2 mission and in helping to define the scientific case.

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I. Community Support Programs

1. End to End (e2e) Operations

Goals for FY 2007

From its inception through the duration of FY 2006, the Division’s efforts focused on building the organization, outlining roles and responsibilities, identifying startup funding, solidifying channels of communication, and determining strategies for action in the Division’s initial years. Many strategic alliances were initiated, from which collaborative proposals for external funding will be issued beginning in FY 2007. Throughout FY 2007, the e2e Operations Division will focus on building the organization, channels of communication, and determining strategies for action in the Division’s initial year. The following have been identified as key activities for FY 2007:

Mission FY 2007 Goals in Support of Mission Broaden access • Develop one federated archive structure for use by all projects in to the NRAO operations facilities • Prepare a full VO-compliant NRAO archive ready for launch of NVO facility • Encourage extensive internal use of the archive query interfaces Increase science • Produce science data products to expand the collection available impact and through Virtual Observatory services throughput Optimize • Answer research questions regarding the NRAO strategy and investments approach for automated data processing • Pursue effective management of joint proposals

Table I.1. Accomplishments in FY 2006 Milestones Delivery Date

Acquire and install ESO/NGAS Archive Software 01/2006 Initial planning for 3rd annual NVO Summer School 04/2006 Draft SSA 1.0 interface 05/2006 SIA 1.1 planning for May IVOA interop 05/2006 Initial draft spectral line list interface 05/2006 IVOA interoperability workshop (Victoria BC) 05/2006 NRAO/NVO archive/VO planning meeting held 06/2006 Scalable data analysis framework prototype 06/2006 NVO/Opticon data analysis frameworks workshop 06/2006 Install archive host prototype #2 07/2006 VOClient software for NVO summer school 07/2006 DAL service reference code in Java 07/2006

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Objectives

The following specific objectives in the areas of National Virtual Observatory (NVO) participation, archive development, proposal administration, scheduling and metrics, and automated data processing will be pursued throughout FY 2007 by the e2e Operations Division, which includes the Data Postprocessing Group that develops the CASA interferometry package.

The NRAO Participation in National Virtual Observatory (NVO) Project and the NRAO Archive Infrastructure & Interfaces for FY 2007

The NRAO continues to be active in NVO technical development, and has recently started the process of planning for a role in the NVO Facility. In FY 2007 the primary goals will be to generate science data products from available historical data stores, make these accessible to the community through applications that consider VO technologies, and fully participate in planning and preparations for the NVO Facility.

Table I.2. e2e Milestones for late FY 2006 and FY 2007 Delivery Milestones Date Draft V1.0 Cone Search specification 08/2006 Draft V1.0 Simple Image Access specification 08/2006 Draft V1.0 Simple Line Access specification 08/2006 NVO Summer School (Aspen) 09/2006 IVOA interoperability workshop (Moscow) 09/2006 Conduct Fall 2006 joint meeting of NRAO/NVO 12/2006 Scalable data analysis framework functional prototype 02/2007 Document physical architecture of existing system 08/2006 Integrate NGAS archive system into existing NRAO science data archive 09/2006 Document role of archive facilities in the NRAO Integrated Science Center vision 09/2006 Develop second-generation archive interface prototype based on existing servlets 10/2006 Updates to SIAP image server 11/2006 Core Science Group releases new archive interface 12/2006 Complete transfer of historical VLBA tape archive 12/2006 Complete transfer of 1.5 TB historical GBT science data 12/2006 Construct global calibrator source database for all the NRAO telescopes (currently 05/2007 led by EVLA Computing)

The NRAO Proposal Infrastructure & Interfaces for FY 2007

A proposal submission tool (PST) developed by EVLA has been in use for VLA and GBT over the past year, which is the first step towards a unified proposal administration process across the NRAO. Over the upcoming year, the existing PST will be transitioned to e2e Operations. At the same time the unified process for proposal administration, which will notably include the addition of VLBA proposals into the model, and addressed in the context of ALMA operations requirements, will be pursued with the goal of seamless joint proposals.

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Milestones Delivery Date

Develop transition plan 09/2006 Effect transition of the NRAO PST & Database to e2e Ops 12/2006

The NRAO Scheduling & Metrics Milestones for FY 2007

Activities are currently underway to investigate or implement dynamic scheduling for each of the NRAO’s telescopes. There is one person working on scheduling algorithms for VLA/EVLA, a project team in place to do the same for the GBT, and a software engineer working to prototype the requirements for ALMA’s scheduling tools. In FY 2007, the role of the e2e Operations Division will be to establish and maintain communications channels between the teams, and to establish a mechanism for continued teamwork in the upcoming years. The ultimate goal in 3–5 years is for the team to identify how to leverage each others’ ideas and tools, and automatically provide the NRAO management with appropriate metadata about what observations have been conducted and how successful they were in generating science.

Milestones Original Date Establish communications with VLA/VLBA, EVLA, GBT, ALMA 08/2006 working groups and staff members Develop coordination calendar for scheduling efforts across Observatory 12/2006

The NRAO Automated Data Processing Milestones for late FY 2006 and FY 2007

Automated data processing involves development of the functionality to analyze and reduce data from each of the NRAO’s telescopes, and in addition, automate the processes so that initial science data products are delivered to researchers for advanced analysis. In FY 2007, lessons learned by automating for the VLA/VLBA will be identified and evaluated for use by the other telescopes.

Milestones Delivery Date

Integrate CASA/GBTIDL milestones into upcoming quarterly reports 09/2006 Meet all targeted milestones for CASA development 09/2007 Select projects for VLA/VLBA pipeline assistance pilot program 05/2006 Schedules generated for all pipeline pilot projects 08/2006 Pipeline reductions for first 50% pilot projects complete 07/2006 Pipeline reductions for remainder complete 08/2006 Pilot plans for Fall 2006 observing complete 09/2006 Data Product Generation Plan complete with detailed assignments for new, 07/2006 temporary data analysts Develop process for augmenting archive with new data products, e.g. 08/2006 images, produced by pipelines VLA/VLBA calibrator polarization monitoring pipeline simplified and 08/2006 transitioned to Socorro data analysts for routine population of the NRAO archive with relevant images and updates to web interface

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Milestones Delivery Date

Institute coordination between all data analysts 08/2006 Summary statistics and report on existing VLA/VLBA pipeline in AIPS 09/2006 Start working through past VLA archive data with AIPS pipelines to 10/2006 generate science products First half of VLA archive processed via pipeline 06/2007 Requirements for pipeline improvements set 09/2007 Second half of VLA archive processed via pipeline 06/2008 Develop plan for common VLA/Chandra sources 12/2006 Explore possibility of common NRAO/HST sources 12/2006 Explore possibility of common NRAO/SIRTF sources 12/2006 Process in place for a data analyst to pipeline and archive straightforward 01/2007 VLA/VLBA observations within two weeks of data availability Feedback from researchers regarding utility of pipelined products available 06/2007 and disseminated

2. Scientific Community Outreach

Fostering a strong scientific community of researchers remains an important part of the NRAO's mission. There are a broad range of activities that are pursued including undergraduate, graduate and post-graduate programs, instrument and visitor programs to enhance University/NRAO collaborations, workshops, schools and conferences, library services, etc. Although many of these activities occur Observatory-wide, the Division of Science and Academic Affairs (DSAA) provides the necessary coordination of these science and academic activities.

Undergraduate Programs

The long-running (since 1959) summer student program continues to be a successful endeavor. The 10– 12 week program allows about 25 students to work under the supervision of an NRAO staff member at sites in New Mexico, West Virginia and Virginia, carrying out original research in the areas of astronomy, computing or engineering. The majority of these students are supported out of funds from the NSF Research Experience for Undergraduates (REU) program, while the remaining (graduating seniors, foreign students, and graduate students) are covered by the NRAO operating funds.

The NRAO also runs a co-op program for undergraduate engineering students that enables them to gain practical, career-based experience as part of their formal academic education. Students from participating institutions work at an NRAO engineering site for two (non-consecutive) semesters. The NRAO technical staff supervises the students and engage them in problems on the technological forefront. On average three students per semester are funded through the NSF Cooperative Agreement.

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Graduate Programs

The NRAO is committed to training the next generation of astrophysicists in the techniques of radio astronomy. Several programs exist for this purpose. First, graduate seniors and first and second year graduate students are able to participate in the summer student program (as described above). This allows the students to gain experience in radio astronomical research early in their graduate careers, allowing them to incorporate these skills into their thesis research. Secondly, the NRAO awards pre-doctoral fellowships to students who have completed the academic course requirements for their Ph.D., so that only their thesis research remains for them to complete. Such students remain in residence at the NRAO, typically for two years, and collaborate with an NRAO staff scientist who supervises them as they acquire data, reduce it and write up their results. Typically there are five graduate summer students and four resident graduate students (called “Junior Fellows”) funded each year through the NRAO operating funds.

In addition to graduate summer students and resident graduate students, more than 100 Ph.D. students make observations with the NRAO telescopes each year. Travel reimbursement, low cost accommodations and computing facilities are provided on-site to assist these students during stays of one to three weeks. The Observatory also supports longer stays (3–6 months duration) for those students who wish to collaborate with an NRAO staff scientist as part of their Ph.D. research. These internships allow graduate students to work closely with the NRAO staff and forge valuable long-term links to the University community.

Financial support is also available for students performing observations on the GBT. Students at U.S. universities are eligible for the program which is designed to provide salary support and miscellaneous expenses such as computers and travel (to a maximum of $35,000). The program is supported through operations funds from Green Bank at a level of $200,000. We anticipate increasing this popular program by 50 percent in 2007, and broadening the eligibility to observing projects carried out at the NRAO facilities.

Postgraduate Programs

The Jansky Postdoctoral Fellowship Program remains one of the top postdoctoral fellowship programs in the world. Jansky Fellows carry out investigations independently or in collaboration with others within the wide framework of interests of the Observatory. In addition to astrophysics research, the NRAO encourages work on radio astronomy instrumentation, computation, and theory. The appointments are made for a two-year term which can be extended for a third year. In a typical year two to four appointments are made. Approximately half of these fellowships are in residence at the NRAO, while the other half are non-residences located at a U.S. university or research institute. Resident fellows are encouraged to spend time at universities working with collaborators during the course of their fellowship, while non-residents are encouraged to make frequent and/or long term visits to the NRAO sites.

In addition to the Jansky Fellows, the Observatory funds the NRAO Postdoctoral Fellows. The appointments are similar to Jansky Fellows, but the NRAO Fellows have responsibilities (up to half time) for the operation and support of the NRAO facilities. In 2006 there were three NRAO Postdoctoral Fellows paid from operating funds from the GBT, ALMA and the VLA.

University-NRAO Programs

Beyond the education and training of future generations of radio users through its programs in undergraduate, graduate and post-graduate programs, the NRAO works to maintain an active U.S. radio community. This is accomplished in a variety of different ways including staff community service, visitor

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programs, the organization of science meetings, and the funding of university-led hardware and software projects.

The NRAO scientific and engineering staff serve on advisory committees and review panels, they serve as AAS Officers and on its committees, they teach university courses, they serve as editors and referees for professional journals, and they give colloquia and invited talks at international meetings. This interaction is further enhanced through the NRAO-organized scientific meetings and workshops through which all scientists have an opportunity reflect on the current direction of astronomical research and the state of current instrumentation or techniques. The Observatory also supports visits by outside Ph.D. scientists and engineers to any of its sites so that they may interact with the NRAO staff. The length of a visit is optional, ranging in duration from weeks (e.g. summer research visits) to months (sabbatical visits).

All of these interactions keep the NRAO scientists engaged in the wider astronomical community and they act as a conduit through which the community can maintain its connection to the NRAO. One of the more tangible benefits of these programs is that they allow for community-wide input into Observatory priorities for science, instrumentation and algorithm development. Likewise, it identifies technical areas where Universities are strong and hence can collaborate with the NRAO. In the description of the NRAO facilities are several examples of university-led software and hardware projects.

3. Spectrum Management

Spectrum management activities are conducted by the NRAO Spectrum Manager in consultation with the autonomous interference protection groups in Green Bank and Socorro. The NRAO community provides advice via the Users Committee.

The spectrum manager represents the Observatory's interests in FCC rulemaking procedures and works with U.S. Government representatives on domestic and ITU issues. The NRAO also supports the work of IUCAF, CORF, etc. which were created to protect astronomy and earth sensing. The spectrum manager works to increase awareness of the unique circumstances of the radio astronomy service on the part of regulatory officials and other spectrum users. There is a large collaborative component because general rules are not formulated on behalf of individual instruments or observatories.

The mission of the NRAO Spectrum Management is to protect observatory operations from harmful interference, to achieve more beneficial observing conditions within the spectrum regulatory regime and to assist other agencies in furtherance of these goals. The spectrum manager is reponsible for the NRAO's FCC and other official U.S. Government filings in rule-making issues of concern to radio astronomy.

Spectrum management activities are driven by ITU and FCC-related cycles which extend over several or many years. Due to politics, no important FCC-related issues concluded during the past year; perhaps 6– 8 issues have been held in abeyance. However, the ITU concluded its deliberations on use of ultrawideband technology and is in the process of wrapping up its decade-long band-by-band studies of protection of passive services from out of band emissions of the active services. ITU adopted for study the subject of national radio quiet zones and adopted a new recommendation related to sharing of the 94.1 GHz band, both of which issues were first formulated by the NRAO. Sharing of this band is important to

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the protection of radio-astronomy receivers, which will be saturated or destroyed by main-beam encounters with newly orbiting 2kW cloud radars such as CloudSat. The work of coordinating between CloudSat and radio astronomy was done almost entirely at the NRAO on behalf of IUCAF and the international community.

There are many pending FCC rulemakings which could progress during 2007 but the hottest topic will be a congressionally mandated program to allow unlicensed devices to use the TV broadcast bands. 2007 will see the rollout of automotive radars at 24 and 76 GHz and the proliferation of devices using ultrawideband technology (1–10 GHz wide emission masks). The great bulk of spectrum management activities in 2007 will be in support of the 2007 November WRC in Geneva. Issues of concern include identification of 1 GHz of “suitable” spectrum in support of airborne telemetry, really national security surveillance by unmanned vehicles, and the prospect of frequency allocations above 275 GHz.

4. Education and Public Outreach

Scope of Operations

The Education and Public Outreach (EPO) program provides leadership for the development of a scientifically and technically literate society; communicates extensively with the astronomical community; functions as an exceptional science education resource; communicates the NRAO mission and science to the media, science museums, and planetariums; creates high-quality publications; operates science centers that bring astronomy to the public; and increases national and international awareness of the NRAO and its programs.

Progress Toward FY 2006 Program Plan Objectives

A program for radio astronomy outreach to science museums and planetariums was inaugurated via collaboration with the Space Telescope Science Institute Office of Public Outreach and the multi-media program ViewSpace. The NRAO EPO delivered a ViewSpace program module that now distributes the NRAO science press releases to 100+ museums and planetariums.

EPO redesigned the NRAO exhibits that are deployed to professional astronomical meetings, such as the January (Washington D.C.) and June (Calgary) American Astronomical Society (AAS) meetings. Two exhibits are being designed for the International Astronomical Union General Assembly (Prague, August): a NRAO exhibit, and an ALMA exhibit (a collaboration with JAO, ESO, and NAOJ).

An Observatory-wide Web Advisory Committee, chaired by the EPO Division Head, is crafting a concept paper that describes the objectives, tasks, and schedule for renovating the NRAO web site and improving its operations and maintenance model. This paper will be submitted to senior management in October.

EPO collaborated with the White Sands Missile Range and the New Mexico Institute of Mining and Technology to celebrate the 100th anniversary of Einstein's annus mirabilis. The Research Experiences for Teachers (RET) program continued, with participants presenting their research results at AAS meetings. The weeklong Education Research in Radio Astronomy (ERIRA) workshop continued as a cooperative effort of the NRAO, the University of Chicago, and the University of North Carolina,

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providing tours and observing projects for high school and undergraduate students. Three-day residential Chautauqua programs in Green Bank and Socorro continued a 20-year NRAO tradition of serving undergraduate science faculty. Green Bank hosted a NRAO / NASA Living with a Star workshop for 15 teachers and followed this with a Hands-On Universe teacher workshop. Teachers are being trained to use both the instruments and the curriculum developed through the NASA-funded Quiet Skies program for their classrooms. The NRAO and New Mexico Tech are offering a two-week course, Radio Astronomy for Teachers, this summer. The West Virginia Governor’s School for Mathematics and Science returns to Green Bank in August, and the Virginia Governor’s School will visit the NRAO Technology Center and Green Bank in late July. GEAR-UP camp, a federally funded program that helps high school students reach and succeed in college, returns to Green Bank. EPO is also collaborating with the Society of Amateur Radio Astronomers to define and seek funding for a pilot program that trains volunteers as the NRAO Navigators, bringing radio astronomy to venues across the U.S.

Nine press releases (3 GBT, 2 VLA, 4 VLBA) have been distributed to date in FY 2006.

EPO initiated several new publications. Design and production are underway for a new Observatory-wide brochure that will debut in September. Two high-quality color posters were produced and were widely distributed to the astronomical community and the general public. EPO Scientist Juan Uson continues to explore radio data visualization techniques and produced several excellent radio-optical composite images. EPO renewed the successful AUI/NRAO Radio Astronomy Image Contest, and the submission deadline for the 2nd annual contest is 1 September 2006.

The CY 2005 attendance at the Green Bank Science Center was 44,717 persons, an increase of 10.0% (4,077 persons) compared to CY 2004. The CY 2005 attendance at the VLA Visitors Center was 21,832 persons, a decrease of 6.3% (1,467 persons) from CY 2004. A $7.2M NRAO–University of New Mexico proposal was submitted to the NM State Legislature in January for the design and construction of a new 15,000 sq. ft. VLA Visitor and Education Center. A new Expanded Very Large Array exhibit was designed and installed at the VLA Visitors Center.

EPO staff participated in numerous community activities, including K–12 science activities in Green Bank, Socorro, and Charlottesville, providing speakers, judges, coaches, volunteers, prizes, and special tours. EPO staff also visited schools to lead science enrichment activities and gave invited talks to civic groups.

Objectives and Schedule for FY 2007

The objectives and schedule for each major EPO FY 2007 Program Plan element are summarized below. The development of metrics for each program element is a priority FY 2007 task.

Legacy Imagery Project

The prize winners for the 2nd Annual AUI / NRAO Image Contest will be announced early in FY 2007, and the 3rd annual contest will be announced at the winter AAS meeting. Four high quality color posters and a 2007 NRAO Calendar will be designed and distributed. EPO will also submit a visually compelling science image for the 2008 AAS calendar. EPO Scientist Juan Uson will collaborate with the Hubble Heritage Team in the production of a prototype NRAO – HST composite image.

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Table I.D.1. Legacy Imagery Project Milestones Item Delivery Date Announce 2nd Annual AUI / NRAO Image Contest prizes 10/2006 Conduct the 3rd Annual AUI / NRAO Image Contest • Announce the contest 01/2007 • Submission deadline 09/2007 Design and publish 4 high-quality color posters • Select 2 images for poster production 10/06 and 03/07 • Two posters complete 12/06 and 05/07 Publish a 2007 NRAO Calendar 12/2006 Submit a NRAO science image for the 2008 AAS calendar 09/2007 Announce a prototype NRAO – Hubble Heritage composite image 05/2007

Science Museum Outreach

The images and storyline created for the new Observatory-wide general public brochure in FY 2006 will be used as the starting point for the design and development of a 10 – 15 minute ViewSpace program about radio astronomy and the NRAO.

Table I.D.2. Science Museum Outreach Milestones Item Delivery Date Produce a NRAO / Radio Astronomy ViewSpace program • Begin design / storyboard 12/2006 • Review design / storyboard with STScI OPO 03/2007 • Final program production complete 09/2007

Astronomical Community

EPO will support and staff the NRAO exhibits at the January and May 2007 AAS meetings. The ALMA and EVLA exhibits will be redesigned prior to the winter AAS meeting. EPO staff will also participate in these key astronomical community events: (a) Astronomical Society of Pacific (ASP) – EPO Community conference; (b) IAU Division XII Working Group “Communicating Astronomy to the Public” conference; and (c) the Southwest Consortium of Observatories for Public Education (SCOPE).

Table I.D.3. Astronomical Community Milestones Item Delivery Date Complete exhibit re-design 12/2006 AAS winter meeting exhibition (Seattle, WA) 01/2007 AAS summer meeting exhibition (Honolulu, HI) 05/2007 IAU Division XII Working Group CAP conference 09/2007 ASP EPO Community conference 09/2007 SCOPE meetings 10/06 and 06/07

World Wide Web (WWW)

Many persons experience their first contact with the NRAO through the WWW, and this electronic interface is arguably the Observatory’s most important outreach and communication tool. Given the scope of our mission, the NRAO website is necessarily large and complex, and it serves a diverse international

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audience. Since there are no full-time WWW operations and maintenance (O&M) personnel, and the last NRAO web site renovation was completed more than five years ago, the site has grown anarchically and developed content, structure, and design issues. To address these issues, the Observatory has declared the improvement of its web site to be a strategic priority and tasked EPO and CIS to define and lead a WWW renovation project in FY 2007. This project’s milestones will be further defined by the WWW renovation and O&M plan currently being developed.

Education

EPO education programs increase public awareness of radio astronomy and the NRAO, improve teacher practice in science and mathematics, and encourage students to consider careers in science, technology, engineering and mathematics (STEM).

Navigators: Trains volunteers to deliver engaging presentations about the NRAO and radio astronomy. The Society of Amateur Radio Astronomers (SARA) has built 20 demonstration radio telescopes for a FY 2007 pilot program with 14 volunteers. Each Navigator agrees to conduct at least 4 outreach sessions per year and reach 100 people.

Table I.D.4. Education Milestones Item Delivery Date Submit NASA IDEAS proposal to fund long-term program 10/2006 Create Navigators website 11/2006

Cosmic Radio: In partnership with a WV public radio station, EPO will produce and distribute 26 episodes of a 2–3 minute radio show about radio astronomy and the NRAO. Distribution will be free to National Public Radio (NPR) and community stations that air these shows weekly over six months. EPO staff wrote the show scripts in FY 2006.

Table I.D.5. Cosmic Radio Milestones Item Delivery Date Complete script recording 11/2006 Launch web site 11/2006 Initiate program distribution 02/2007

Traveling Exhibit: EPO staff queried small museums and planetariums regarding their interest in a traveling exhibit about radio astronomy. Since interest was high, an exhibit firm completed a conceptual design, and grant funding is being sought for a two-year exhibit development cycle.

Table I.D.6. Traveling Exhibit Milestones Item Delivery Date Submit grant proposal to NSF (MPS-IPSE) 02/2007 Conduct prototype exhibit evaluation 10/2007

Quiet Skies: Funded by an on-going NASA IDEAS grant and continuing in FY 2007, Quiet Skies introduces students to radio astronomy via a study of Radio Frequency Interference (RFI).

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Table I.D.7. Quiet Skies Milestones Item Delivery Date Initiate EPO community discussion re making Quiet Skies 01/2007 widely available Modify the curriculum and web site based on field test results 04/2007 Market Quiet Skies to school & teachers 05/2007–10/2007

Twin Cities: This program will enable educational and cultural exchange between San Pedro de Atacama in Chile and Magdelena, NM in the USA. These towns are both small communities located in relatively undeveloped regions of high-elevation desert near major radio astronomy facilities. These towns have cultural similarities, and the majority of their populations are people of native or Spanish ancestry. This program will sponsor an exchange of up to three teachers per year, and enable cultural and educational exchanges via video-conferencing and the Internet.

Table I.D.8. Twin Cities Milestones Item Delivery Date Complete Twin Cities agreement 11/2006 First teacher exchange 06/2007

As a national research center, the NRAO is uniquely qualified to influence science-teaching practice by involving teachers in real-world research experiences. The Observatory will host the following residential programs for teachers in FY 2007:

• Astronomy Institute (GB) 20 K–12 teachers, 1-week summer residency • Chautauqua Program (GB, SOC) 40 undergraduate faculty, 3-day summer residency • Research Experience for Teachers (GB, SOC) 3 to 5 high school science & math teachers, 8-week summer residency

The NRAO educational programs for students seek to engage their interest in STEM careers before they have made their key academic or career decisions.

• WV Governor’s School for Math and Science 60 rising 9th grade students, 2-week summer residency • Gaining Early Awareness and Readiness for Undergraduate Programs (GEAR UP) 20 local rising 9th grade students, 2-week summer residency • Gadgets and Gizmos in Modern Science 16 middle-school students, semester elective taught by the NRAO scientists

News/Media

EPO will design and implement a “virtual pressroom” at the NRAO web site to showcase items of interest to the media, including fact sheets, press releases, images, experts available for interviews, and media contact information. As ALMA and EVLA construction progress towards Early Science, EPO will increase its efforts to raise their visibility to the news media and the general public. EPO will also implement metrics designed to measure the effectiveness and media penetration (quantity and quality) of the Observatory’s press releases.

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Table I.D.9. News/Media Milestones Item Delivery Date Virtual pressroom operational 12/2006

Publications

Table I.D.10. Publication Milestones Item Delivery Date Edit and publish NRAO Newsletter 10/2006, 01/2007 04/2007, 07/2007

Science Centers

The Green Bank Science Center and the VLA Visitor Center are popular. The programs and tours enabled by these facilities and the on-site EPO staff in WV and NM made visiting these NRAO facilities an enjoyable, enriching experience for more than 66,000 people in CY 2005. The visual impact of the GBT and the VLA and the intriguing, well-publicized accomplishments of modern astronomy are major draws. The two NRAO science centers serve our primary education mission, providing the general public with year-round access to our telescope facilities and research. In FY 2007 EPO staff will seek funding for a new VLA science center. EPO will also initiate a collaboration with the University of Virginia to seek funding for a new science center in Charlottesville. Funding for new outdoor exhibits at the VLA will be sought from the NSF Informal Science Education Division.

Table I.D.11. Science Centers Milestones Item Delivery Date Submit VLA Visitor Center proposal to NM Legislature 01/2007 Submit proposal for new outdoor exhibits at the VLA 06/2007

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J. Management and Infrastructure Services

1. NRAO Organization

The NRAO is operated by Associated Universities, Inc., under a cooperative agreement with the National Science Foundation. AUI delegates the management of the Observatory to the NRAO Director who is supported by the senior management team. In FY 2006 the NRAO completed a number of new appointments to its senior management team. This section describes the resulting management structure. The NRAO Organization Chart and senior managers are provided in Figure J.1.1. The NRAO completed a number of appointments to its senior management team in FY 2006.

Figure J.1.1. The NRAO Organization Chart.

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The NRAO is operating three major telescope facilities (GBT, VLA/EVLA, and VLBA), undertaking two major construction projects (ALMA and EVLA), and establishing the NAASC for the operational phase of ALMA. All these activities are supported by administrative and technical support divisions and the Central Development Laboratory. All these activities are organized into four main areas: (1) NRAO (non- ALMA) Operations, including the EVLA project, (2) the ALMA Project, which includes the construction project and the NAASC, (3) the Division of Science and Academic Affairs (DSAA, see below) and (4) Administration.

The NRAO Director directs the running of the Observatory and reports to the AUI President. The leaders of the four areas, as given in Figure J.1.1, report to the Director. The Deputy Director, besides acting as Director in his absence, is the chief operating officer of the Observatory responsible for the day to day operations of the NRAO (concentrating on the non-ALMA part of the Observatory), i.e. (1) above. NA ALMA Project Director is responsible for the NA ALMA Project, (2) above. The Head of DSAA is responsible for (3) above. The Associate Director for Administration oversees the budget and the business support functions of the Observatory, (4) above.

In addition, there are the New Initiatives Office (NIO) and Chilean Affairs Office, with the heads of both reporting to the Director. The Head of the Program Management Office (PMO) reports to the Deputy Director in his role as chief operating officer.

The telescope operations groups (GBT and VLA/VLBA), each headed by an Assistant Director, are organized along the general structure presented in Figure J.1.2. The Head of Science Operations, who may be the Assistant Director or the Deputy Assistant Director, is responsible for coordinating the delivery of science capabilities to the users. The Head of Project Management coordinates development projects directly associated with the telescope. In practice, staff members from the operational-support divisions (electronics, software, etc.) are deployed to projects through a matrix management system.

The ALMA Operations embodied in the NAASC is organized differently because it is embedded within an international collaboration.

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Telescope Operations Model

Assistant Director

Deputy Assistant Director

Head of Site Head of Head of Site Infrastructure Principal Scientist Business Science Project (Plant, Administration Operations Management Computing)

Staff Scientific Research & Scientific User Scientific Planning Support

Electronics Support & Development

Mechanical Engineering & Engineering Services

Software Support & Development

Telescope Operations

Figure J.1.2. The Telescope Operations Model.

A number of groups and divisions provide common services to or coordination among the operations across the Observatory. They are overseen by the Deputy Director, as chief operating officer.

The Administration group is headed by the Associate Director for Administration and consists of the Business Services, Fiscal, Contracts and Procurement, Human Resources, and Safety groups. The Program Management Office provides project management, program development, and program assessment services to the entire Observatory. The End-to-End Operations Division is responsible for development and deployment of Observatory-wide scientific services to the user community. These services range from proposal submission through Virtual Observatory image access. The Education and Public Outreach division provides press information, educational services, and visitor-center operations for the Observatory. The Computing and Information Services group provides computing hardware and a common computing environment for the Observatory. The Central Development Laboratory provides

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state-of-the-art microwave and digital devices for the operating telescopes as well as serving as the research and development arm for next-generation instrumentation.

Division of Science and Academic Affairs

The Division of Science and Academic Affairs (DSAA) coordinates and oversees scientific and academic activities across the Observatory to make sure the Observatory mission is fulfilled optimally. In particular, the services provided by DSAA can be sub-divided into two main areas: (a) Science Community Development to foster radio astronomy user community and (b) Science Research to facilitate staff research.

(a) Science Community Development focuses on those activities which provide services to the wider astronomical community outside the NRAO, with the goal of fostering a strong U.S. radio astronomy community. The many activities include research programs to employ undergraduate (NSF REU program and engineering co-op students), graduate (Junior Fellows), and post-graduate (Jansky Fellows, NRAO Postdoctoral Fellows).

The DSAA also manages the peer review process for the allocation of telescope time for all of the current NRAO telescopes. As part of this process, funding is provided to travel to the telescope, student research support as well as computing and page charge support. In addition to these activities, a healthy and active US radio community is supported though the funding of University-led hardware and software projects, NRAO staff community service, and the organization of science meetings.

(b) Science Research at the NRAO: In order to provide the science planning and functional support to ongoing NRAO facilities it is necessary to have a vibrant, world-class research staff. The hiring of scientific staff, their assignment to functional roles within the Observatory, and the evaluation and career tracking processes are all coordinated by DSAA. Close links between NRAO staff and the University community are encouraged through visitor programs to the NRAO, short-term University sabbatical visits of NRAO staff and the exchange of staff for scientific colloquia.

2. Administration

Environment, Safety, and Security (ES&S)

Overview

The NRAO has applied significant resources to the development of the ALMA Safety Program and to the continuous improvement of the Observatory ES&S Programs during FY 2006. The NRAO makes great efforts to assure that safety and security considerations are incorporated into our decisions. The approach to achieve our goals includes the involvement of Site Safety Committees to act as a voice for all employees in expressing safety issues and to mitigate potentially hazardous conditions.

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Progress toward FY 2006 Program-Plan Objectives

ES&S formalized an Asbestos Management Program for use in facilities where asbestos has been identified. This program includes training specific employees in management and disposal procedures for asbestos materials and overseeing all asbestos-removal projects to ensure the health and safety of employees and visitors.

The NRAO completed an Observatory-wide environmental compliance audit in FY 2006. Thanks to our continued commitment to the protection and enhancement of the environment for research and administrative operations, no significant findings were noted. Within the NRAO, Observatory management establishes the standards that all employees have the responsibility to act consistently with environmental principles and objectives.

ES&S provided frequent safety education and awareness training to affected employees. Additionally, ES&S began a proactive program of inspection and training for the VLBA facilities. ES&S developed a VLBA-specific site inspection checklist designed to identify deficiencies and suggest corrective actions.

ES&S successfully developed the ALMA Safety Program. This program was reviewed by ESO, the NRAO, and the NAOJ to ensure compliance with international requirements. The ALMA Safety Manager is responsible for its implementation.

ES&S initiated efforts to develop the NRAO security program. Proposals were developed for the implementation of video surveillance systems and card access at NRAO facilities. ES&S will continue development of remote monitoring of common areas at Green Bank where problems were encountered to ensure that RFI associated with the surveillance is appropriately mitigated.

Objectives and Schedule for FY 2007

In the coming year ES&S will address any deficiencies noted in the Environmental Audit and will establish written environmental policies for site projects that may have an impact on the environment. ES&S will also make a site asbestos inspection at Socorro. This inspection is necessary owing to the age of our facilities and the potential for employee exposure. The inspection will identify areas where asbestos may need to be considered. If asbestos materials are identified, the affected spaces will be included in the NRAO Asbestos Management Program to ensure the health and safety of employees and visitors.

The Observatory Occupational Safety Program is a fully mature program that has been implemented on every level within the NRAO. An effective safety-management system must be led by senior and line managers and supported by safety representatives. When a safety system becomes mature, managers and supervisors must remain aware of the potential for accidents and injuries in the workplace. In order to maintain this type of system, management must proactively and constructively participate in the formulation of safety policies and procedures. In the coming year, ES&S will help by clarifying the roles and responsibilities for all affected personnel, at every level, and by providing safety education and awareness training appropriate to the level of each employee. The clarification of NRAO policies will result in a completely updated Safety Manual that should reduce occupational injuries and illnesses for all employees. ES&S will form an employee safety committee at the Charlottesville site. This committee will provide a direct avenue to communicate employee safety concerns. Also in the next fiscal year, ES&S will continue ALMA System Safety reviews and will work within the acceptance and verification process for antenna components.

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The NRAO is committed to protect its staff and visitors as well as to preserve personal and government property from damage or loss. ES&S has identified two areas where additional resources may enhance the security and safety of our visitors and staff. They include improving the surveillance system at the NTC and identifying staff as well as visitors. ES&S will draft proposals for improving surveillance and identification systems on an Observatory-wide basis.

Conclusions

The NRAO will continue to be a leading example in environmental protection and to reduce the number and severity of accidents at our facilities. The Observatory will also continue to identify methods to improve the security of our facilities via non-invasive methods. With the support of local and senior Observatory management, the ES&S Division will continue to provide guidance for protection of the environment, and support a safe and secure workplace for our staff and visitors.

Observatory Business Services (OBS)

Overview

The Observatory Business Services division provides management and support for budget development and analysis, procurement, grants, agreements, facilities, and general business matters for Charlottesville operations and observatory-wide requirements.

During FY 2007 OBS will continue to cultivate its available resources to provide accurate and timely information to attain a superior level of business support. This will be accomplished through the adoption of best practices, leading-edge business information tools, and more tightly integrated processes. Some of the planned enhancements include:

• Implement a secure shared-server budget-development and change-tracking application. • Expand the facilities and services help-desk application. • Implement a visitor’s reservation and new employee arrival tracking application. • Develop web-based or WIKI-based WBS and chart-of-accounts change requests. • Develop the Observatory Facilities Plan. • Continue to cross-train employees in all support functions.

Contracts & Procurement

The ALMA construction project has markedly increased the volume and complexity of procurement and Import/Export (I/E) activities across the Observatory. To meet this challenge the Contracts and Procurement division is expanding its efforts to cross-train its buyers and provide highly focused educational opportunities. The integration of I/E functions by the North American, European, and Japanese ALMA partners has also had a workload impact throughout OBS. To facilitate a more responsive level of support in FY 2007, the Contracts and Procurement division will:

• Implement a secure server or WIKI-based procurements and contracts tracker. • Fully implement the Procurement Professional Training and Advancement program. • Expand the Import/Export training and education program. • Continue to cross-train buyers in all procurement functions. • Conduct in-house contracts training sessions for buyers.

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Facilities

NRAO Edgemont Road

The 32,291 square-foot addition at Edgemont Road is complete, and attention is now focused on renovating offices and replacing the aging heating, ventilation, and air conditioning (HVAC) system hydronic piping in the original building. The old HVAC piping will be replaced over a three- to six-month period at an estimated cost of $707,000. The piping replacement was initially scheduled for FY 2006, but a seven- month delay was incurred due to engineering design considerations and finance negotiations. The project will be paid for through the maintenance reserve fund incorporated into the facility lease and therefore will not present any additional expense to the NRAO Operations budget.

NRAO Technology Center (NTC)

The ALMA construction project has introduced many physical changes and equipment installations to the NTC. During FY 2007 the NTC support will focus on facility-wide enhancements as well as several safety and security needs. Specific tasks include:

• Electronic access control system • Surveillance camera system • Central fire detection and reporting system • Parking-lot lighting • Increased compressor-room ventilation • 50 Hz power with full UPS backup • Dehumidification equipment/system • Machine shop particulate exhaust system • Additional office space

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Fiscal Division

Overview

The NRAO strives to maintain a financial management and reporting system that exceeds all internal and external requirements. To achieve this goal, significant effort was devoted to the transition of three fiscal functions to electronic processing during the current fiscal year. NRAO management also proposed modifications to specific policies and procedures to ensure adherence to federal regulations and good business practice.

Progress toward FY 2006 Program-Plan Objectives

The NRAO completed an update of the Chart of Accounts to correlate with the implemented Work Breakdown Structure (WBS) system. Expansion of the WBS system provided more detailed geographical reporting capability and the addition of multiple WBS levels within each project.

As of January 1, 2006 the payroll function was converted to the central database of JD Edwards/Peoplesoft, effectively maintaining labor data in a central location to meet expected reporting requirements.

An Electronic Time Keeping system (ETK) is being implemented, and employees assigned to a variety of designated focus groups are currently testing a prototype. The web-based ETK system will allow for time and project tracking of labor costs, thus increasing the efficiency of the payroll process.

Objectives and Schedule for FY 2007

We will establish a long-term plan to ensure the maturity and continued development of the payroll system, and we will identify internal resources to resolve ongoing issues. We will study the efficiency of generating payroll checks and doing payroll-tax processing in house as an alternative to contracting these services.

We will continue refining our reporting capabilities based on the expansion of the Chart of Accounts, WBBS, and company structure to ensure current, accurate, and complete financial reporting.

The NRAO has implemented detailed policies and procedures to safeguard and accurately report the financial assets of both the NSF and the NRAO, and we continually review these policies to ensure adherence to all requirements and regulations. Revisions to the travel policy are in process, and we are reviewing the possibility of incorporating locality-based M&IE and actual lodging rates. The Procurement Policy is scheduled for completion in FY 2007.

We will establish an NRAO/AUI audit plan to evaluate and improve the effectiveness of risk management and internal controls. Management will design and establish an internal audit to evaluate the integrity of financial information, compliance with policies and procedures, and the efficient use of resources. Additionally, quarterly reviews of the purchase-card program and petty-cash reconciliations will be performed to assess vulnerabilities and identify improvement opportunities.

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Human Resources (HR)

Overview

The Human Resources Division, in partnership with NRAO management, ensures a qualified, diverse, and highly motivated workforce focused on achieving the strategic goals of the Observatory through the development of cost-effective and results-oriented human resource programs, policies, and practices.

With the inclusion of the ALMA Observatory in Chile and the EVLA construction project plus projected new project development as discussed in the section on future science, the HR division will continue to focus over the next several years on defining methods to streamline the work of a small human-resources staff. In this regard, the division will advocate an addition to the HR professional staff.

Human Resources Information Systems

The Human Resources Information System provides the resource to meet the Observatory’s informational needs. Vital personnel data are demanded by every conceivable customer. These demands range from management reports of personnel count and labor allocation to requests from funding sources to compliance reporting and benefit support.

The HR staff will continue to be an important partner in a new fully integrated web-based system with the payroll, general ledger, procurement, and a new production time-tracking system. Early in the second quarter of FY 2006 the HR staff had converted to the new database and tested the integrity of the enhanced system that was the critical element for the Payroll division’s first paycheck runs in the new system. The HR Division continues to work with the implementation consultants to bring the system to an acceptable level of efficiency.

Future efforts will include refinements of the Employee Self-Service module and implementation of an ETK system. As the designated employer of all Chilean local staff, the HR division will identify a database system capable of tracking critical employee and supervisory data that meets the regulatory requirements of Chile, the sponsoring partners, and senior management.

Compensation and Benefits

The FY 2006 salary benchmarking report confirmed that NRAO employee salaries overall remain closely market competitive with the rest of the research community. Noted was erosion in entry-level science and engineering position salaries. We must be concerned with salary-grade compression due to limited budget increases. The NRAO is unable to move the salary grades by the amount recommended by the compensation consultants. With “full employment” nationally and inflation on the rise, the Observatory must encourage the science board to enhance salary pools of science and professional engineering staff.

The benefits plans of the Observatory continue to be strong recruitment and retention tools in a time of tight budgets. The Division rolled out a four-tier premium schedule for the employee portion of the medical insurance plan. The goal was to distribute more equitably the medical-insurance cost burden by salary level Federal legislation created Medicare D, the prescription drug option, for retirees. The Division was extremely successful in educating its retirees, the vast majority of whom chose to maintain their Observatory-sponsored coverage; this in turn is projected to reduce the NRAO’s costs. As healthcare costs continue to escalate, the Observatory will have to consider modifications to the plans.

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Diversity

This year the Observatory exhibited at the National Society of Black Physicists (NSBP) and the National Society of Black Engineers (NSBE) conferences. Special emphasis was placed on communicating student programs at the NSBE conference owing to the lack of engineering job openings during the period. The Division will exhibit at the NSBE conference in FY 2007. The scientific conference will be designated early in the Fiscal Year.

The Division took the lead in forming the Observatory’s Ad Hoc Committee on Diversity, which will this year become a standing committee. Originally mandated to identify better methods of recruiting future scientists and managers, the Committee will focus its efforts on analyzing recruitment policy, formalizing selection policies and procedures, and training hiring authorities in the selection process. The committee is evaluating the Observatory HR-related policies and procedures to incorporate pertinent elements of the “Pasadena Recommendations” as endorsed by the AAS Council in January 2005.

The Division made an initial cooperative-education program contact with Howard University and Norfolk State University to discuss a possible Co-Op program relationship. This effort will not be explored further until specifically designated funds can be guaranteed without jeopardizing current co-op institution relationships. The HR Division will continue to encourage and support the establishment of internship programs at the Masters level in engineering and computer science.

Non-Immigration Visas and Expatriate Activity

Like most research institutes, the Observatory has been severely impacted by the recent national and international security concerns raised by the national tragedy of 2001. The process of filing and maintaining non-immigration visas is no longer a small administrative task but has become a significant focus of time and effort. The Observatory continues work with ever-changing Federal requirements in the Exchange Visitor and Non-immigrant work-visa application and processing regulations.

Major emphasis will be placed on visa activity of Chilean national employees who will be on short-term assignments to the U.S. for instrument training and then return to the ALMA site for service. Expatriate assignments for U.S.-based employees will increase and will require significant HR administrative effort.

Training and Development

In FY 2007 the Division intends to sponsor a supervisor/management training program with staff assistance by the UNM Anderson School of Professional Management.

We anticipate the need for structured expatriate and foreign-national acclimation programs beginning immediately. To encourage U.S.-based employees (and families) to accept assignments with the ALMA Project and ultimately the ALMA Observatory and to reduce the stress on foreign nationals (and families) on assignment in the U.S., the HR Division will develop acclimation programs that may include pre- and post-relocation support services and training.

ALMA/Chilean HR Policy

The Division completed, received approvals, and implemented the Internal Rules and Regulations for the Chilean HR Division of the ALMA Observatory. This document has been submitted to the Chilean Labor Ministry and full-scale hiring of Chilean local staff may begin. The Human Resources Manager for ALMA in Chile has been hired and is in place.

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Future efforts include the need to integrate the HR Manager into the AUI/NRAO business philosophy, support the division’s brisk hiring plan, assist with development of supervisor and new-employee training programs, and implement an expatriate (and family) acclimation program. Training for the Chilean management and supervisory staff regarding ALMA policies and employee relations must be developed to promote a positive work environment and employee relations as the ALMA Observatory takes shape.

New Program Initiatives

The next several years promise to provide several programmatic opportunities (i.e. NAASC, FASR, SKA, etc.) for the HR division to provide HR expertise in manpower costing, staff transition planning, immigration issues, etc.

3. Computing and Information Services (CIS)

Table J.3.1. Milestones Achieved in FY 2006 Delivery Milestones Date 1. 20 Mbps network service among the major NRAO sites 11/2005 2. New email quarantine service fully deployed 01/2006 3. Migration of Windows systems to AD domain complete 01/2006 4. Deployment of Google Mini for searching internal web pages 03/2006 5. Upgrade of the central disk filer in Charlottesville 04/2006 6. System administrators meeting in Socorro 04/2006 7. Begin new CCE coordination for Apple OS/X 04/2006 8. Deploy new central Ethernet hub in Green Bank 05/2006 9. Upgrade the main web server 05/2006 10.Upgrade capacity of the Google Mini search engine 05/2006 11. Draft data-security policy 07/2006 12. Migration to RedHat Enterprise Linux 4 complete at all sites 09/2006

Table J.3.2. Milestones for FY 2007 Delivery Milestones Date 1. Adopt a data-security policy 10/2006 2. Increase network connectivity in Charlottesville 10/2006 3. Deploy the inventory database of computer equipment 10/2006 4. Increase network connectivity between Socorro and the VLA 12/2006 5. Decision on unified login profiles 01/2007 6. Upgrade the central disk filer in Socorro 04/2007 7. System administrators meeting in Green Bank 04/2007

Program Plan FY 2007 J. Management and Infrastructure Services 103

Security

The NRAO adopted a Security Policy in 1999. This establishes guidelines for operating securely in a potentially hostile Internet environment. It includes the creation of a security committee with the mandate to recommend action on computer and network security issues, to track ongoing vulnerabilities, to respond to inappropriate use of our facilities, and to continue an education program for our employees. The adherence to this policy has led to an extremely reliable environment for the observatory to pursue its operations, with no major interruptions reported.

There have been several incidents recently—widely reported by the news media—of confidential data exposed by the irresponsible actions of computer users. Although this issue is implicitly covered by our adopted Security Policy and Computer Use Policy, we propose to add an explicit enhancement to our security policy to cover the security of data. A draft of this policy has already been circulated for comments.

Observatory-wide Coordination

In FY 2007 the NRAO will develop a single database of all computing and networking equipment as well as licensed software. An up-to-date and accurate database will greatly simplify budget planning for upgrades, tracking of maintenance contracts, etc.

Common Computing Environments (CCEs)

At present, NRAO employees have different login profiles for different sites and different services. We will examine reducing the number of user identifiers and passwords that our users require to access NRAO network and computing services.

The ability of the new range of Apple Macintosh machines to run both Unix and Windows software is proving to be popular with the scientific staff. We have started a CCE project for these. This will be developed further so that we can provide a fully supported environment, just as we do for Windows and Linux on PCs, including also the newer Mac architecture with Intel-based processors.

Recurring Costs

Storage for data needed by individuals for their operational duties is provided on a central data filer at each site. We have installed or upgraded the filer at each site on a rotating basis. In FY 2007 we propose to upgrade the filer in Socorro.

Information Infrastructure (Web Services)

CIS will work with all NRAO divisions to develop and implement a content-management plan for the NRAO web site in FY 2007, with the goals of improving the usability of the site both for external users and for NRAO staff, and of ensuring timely updating of content.

The upgrade of the inter-site network links to partial DS3 (20 Mbps) may allow more use of cross-site file systems. The performance of this will be evaluated and, where appropriate, use will be made of the technology to unify cross-site services and resources.

Program Plan FY 2007 J. Management and Infrastructure Services 104

There is always a need for NRAO staff (and observers) to access internal NRAO services from external networks when on travel or at home. Although such access is provided, it is not always convenient. We will examine ways to improve this.

Networking and Telecommunications

We will upgrade the link between the AOC in Socorro and the VLA site to OC3 (155 Mbps). We will investigate increasing the bandwidth available to the Internet and Internet2 through our host universities (UVa, NMIMT, and UNM). We will also investigate providing improved access using existing networks between the NRAO and its partner organizations, NRL/UNM (LWDA), DRAO (EVLA), ESO and Santiago (ALMA).

We will investigate improved network-monitoring capabilities to analyze network usage both inside our facilities, among our sites, and to other sites.

4. Program Management Office (PMO)

FY 2006 Accomplishments

While this is not a traditional PMO role, the NRAO PMO continues to lead the modernization of Observatory business services and systems by implementing the NRAO Web-Based Business Services (WBBS). The objective of the WBBS system remains to improve the accuracy and timeliness of all business information, to provide the foundation for project management controls, to reduce administrative effort of the Observatory administration and operational business units, and to generate early-warning triggers so NRAO project managers can launch mitigation strategies that will prevail in meeting the critical path of these projects.

During FY 2006 the PMO focused substantially on the implementation, prototype testing, training, deployment, and initial operation of the WBBS services.

Web-Based Business Services (WBBS)

The WBBS suite consists of the seven major business-service modules, including a major hardware and software upgrade of the Enterprise Resource Planning (ERP) environment and four significant Fiscal sub- service modules as shown in Figure J.4.1.

Program Plan FY 2007 J. Management and Infrastructure Services 105

Web Based Business Services

Human Employee Self ERP Hardware & Procurement Fiscal Payroll Electronic Resources Services Software Business Business Business Time Keeping Business Business Upgrade Service Service Service Service Service Service

Accounts Accounts General Ledger Job Cost Receivable Payable (GL) (JC) (AR) (AP) Figure J.4.1. WBBS Services and Sub-Services.

In FY 2005 the PMO placed the first module of the WBBS initiative into service. The Procurement service or Procure to Pay (P2P) initiative has been very successful in improving the communication, status, and processing of purchase requisitions. P2P has allowed the Observatory to track purchase requisitions in real time, reduce turnaround time for a requisition, and streamline the approval process. In many cases the result has been a much more responsive Procurement organization; tracking and reporting capabilities have been placed in the hands of users and managers. In FY 2006 the implementation team has expanded the capabilities of the P2P service to other e-commerce initiatives such as Procurement Cards (P-Cards), Travel cards, and e-Procurement of commodities through national contracts. Once these initiatives are fully implemented, the cost of processing a purchase order can be reduced by up to fifty percent.

Operational data for the P2P service from activation to date are shown in Table J.4.1 below.

Table J.4.1: WBBS P2P Operations Data Since Inception Procure to Pay (February 2005) Requisitions Processed 9950 Total Line Items 49,750 Total Amount in Requisitions $73.3M Personnel Trained To Date 279 Requisitions have been exclusively paperless since July 15, 2005

The Accounts Receivable module of the Fiscal service also went live in FY 2005 and remains in initial operations and maintenance mode.

The WBBS system required a significant Enterprise Resource Planning (ERP) upgrade to satisfy the requirements for a centralized data base, web-based operation for the entire Observatory staff, operational backup systems and power, and system security.

This significant hardware and software upgrade was completed on time and on schedule without interruption to the ongoing Observatory administration functions. The WBBS architecture upgrade included the installation of the NRAO’s first hardware firewall that incorporates industrial-strength system security into the NRAO WBBS architecture. The deployment of this firewall, while a significant investment, demonstrates the PMO’s commitment to data security. Figure J.4.2 shows the NRAO WBBS hardware and software architecture.

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Figure J.4.2: WBBS Architecture

In March 2006 a WBBS Review was held. The review was chaired by the Observatory Deputy Director. The review covered the currently deployed WBBS including: Procure-to-Pay, Human Resources, Fiscal, Employee Self Services, and Payroll. Subject specialists and presenters were assigned by the chair to support the review of each of the service modules. The review panel generated a report that provided significant feedback from the WBBS user community conveying a spectrum of concerns about overall usability compared to previous systems, additional features needed, work flow, expert-user support, and operations and maintenance support. Priorities were assigned to addressing the concerns associated with each of the WBBS service modules.

A total of 68 trouble tickets were generated from the WBBS review report. The Deputy Director, the Program Management Office, and the Administration are currently working with the report panel members to implement changes to the WBBS services to resolve the user issues. In some cases, other software Commercial off the Shelf (COTS) products are being assessed in a cost-benefit tradeoff to address some of the limitations introduced by the current COTS product—PeopleSoft EnterpriseOne.

Table J.4.2 lists a summary of the planned and completed milestones for the PMO in FY 2006.

Table J.4.2: FY 2006 WBBS Milestones Service Status Completion Date Architecture Upgrade Operational 08/2005 Accounts Payable Operational 10/2005 Job Cost Operational 10/2005 General Ledger Operational 10/2005 Human Resources Operational 11/2005

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Service Status Completion Date Employee Self Services Operational 12/2005 WBBS Help Desk Operational 12/2005 Payroll Operational 01/2006 Medical Change Order Completed 01/2006 Firewall Installation Completed 06/2006 AUI PeopleSoft Conversion Completed 07/2006 Procurement Completed 08/2006 WBBS CCB Pending 09/2006

PMO FY 2007 WBBS Plans

Completion of the WBBS Initiative is planned for early FY 2007. Table J.4.3 shows a summary of the planned WBBS milestones for the PMO in FY 2007. At the conclusion of the development and implementation phase of WBBS, responsibility for Operations and Maintenance (O&M) will transfer to the Observatory’s administration group (anticipated at 2/2007).

Table J.4.3. FY 2007 WBBS Milestones Completion Service Status Date WBBS O&M Contract Start Pending 10/2006 Electronic Time Keeping Implementation 2/2007 WBBS Service Review Implementation 12/2006 WBBS O&M Transition to Implementation 2/2007 Administration Group

FY 2007 Performance-Based Project Management Plans

After the transfer of O&M to the Administration Group, PMO focus will turn to the Performance-Based Project Management (PBPM) Initiative, the concept of which is described in detail in the Long Range Plan. The primary PMO objective in this area is to prepare for and hold a review with NRAO senior management and external experts which will examine the plan for scope, schedule, and budget. Detailed implementation planning will occur after this review.

Table J.4.4. Summary of PMO PBPM Objectives and Targets for FY 2007 Milestones Date Performance Based Project Management (PBPM) 3/2007 Conceptual Design Review PBPM Implementation Design Review 4/2007

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K. FY 2007 Preliminary Financial Plan

The NRAO preliminary financial plan for FY 2007 was written to the Presidential Request Level (PRL) budget of $50,740k for the NRAO operations (including ALMA operations). This sum breaks down as $41,324k for the NRAO non-ALMA operations, $5,721k for EVLA construction, and $3,695 of new funds for ALMA operations. Per instructions from NSF, $2,000k of FY 2006 NRAO operations funds will be carried over to FY 2007 for ALMA operations, which will provide a total of $5,695k for ALMA operations in FY 2007. ALMA construction funding is $47,890k, consistent with the original funding profile (before rebaselining).

The NRAO Senior Management Team conducted an FY 2007 budget review in the spring of 2006. The Director’s Office and Head of Administration provided each business unit with a target budget to cover basic operations. Requests for operational increases, capability enhancements, and infrastructure improvements required written justifications. A budget review committee evaluated these requests and presented recommendations to the NRAO Director for final review and approval. The operations and development plans presented in the preceding sections of the FY 2007 Program Plan follow the results of this process and are consistent with the PRL budget.

The detailed FY 2007 financial plan is presented in the following tables.

Table K.1

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Table K.2

Table K.3

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Table K.4

Table K.5

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Table K.6

OBSERVATORY WORK BREAKDOWN STRUCTURE

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Table K.6 – continued

OBSERVATORY WORK BREAKDOWN STRUCTURE

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After priority obligations were met, a number of important initiatives could not be funded. Should additional funds become available, the NRAO would pursue a number of strategic items, each of which would yield a significant scientific return to the community:

EVLA Commissioning Scientists: Owing to budget cuts and staff attrition, VLA/VLBA Operations have about seven fewer staff scientists than in 2000. Additional scientists are needed for scientific commissioning and early operations of the EVLA. This shortfall has been partially addressed through redirection of resources and staff redeployments, but 4–5 additional staff scientists are needed. They could be phased in over the next 2–3 years. In FY 2007 the NRAO could use two additional EVLA Staff Scientists at a total cost of $139k/yr.

GBT Instrumentation Engineers: The GBT continues to push toward λ = 3 mm operation, but the Precision Telescope Control System (PTCS) project team is below critical mass. The NRAO has also partially addressed this issue within the limits of budget by hiring a new instrumentation scientist who will be assigned to the GBT PTCS project for the next three years. Two additional digital engineers are needed along with some material and services (M&S) funds. The total costs are $212k/yr for personnel and $20k/yr for M&S.

Research and Development Engineers: Most of the NRAO’s research engineers have been engaged in ALMA and EVLA construction during the past few years. R&D of next-generation devices and instruments, which is critical for new scientific breakthroughs, has dwindled to seriously low levels. Within the available budget, the NRAO has directed some funds to this area but is still well short of a robust R&D program. This program can also be phased in over several years. In the near term, two additional research engineers at a total of $212k for personnel and $200k for M&S are needed.

These and other specific requests that could not be budgeted within the PRL are tabulated below.

Table K.7 Strategic Capability Requests Not Funded Within the PRL FY 2007 M&S Labor EVLA Commissioning Scientists Software Scientist $79.5 Commissioning postdoc $59.6 GBT Instrumentation Engineering Advanced Metrology Development $20.0 $212.0 New Instrument Development $185.0 CDL R&D Engineering Focal plane arrays $200.0 $106.0 Advance Receiver Development $70.0 $106.0 VLBA Development eVLBI development $100.0 Science and Academic Affairs Student Support Student Observing Grants Program $100.0 Program Management Office 2 staff members for Performance-Based Project Management $180.0 0.5 FTE contractor support $96.0

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Strategic Capability Requests Not Funded Within the PRL FY 2007 Human Resources HR Specialist $46.6 New Initiatives Office SKA Project Scientist $106.0 Education and Public Outreach NRAO Navigators (community outreach) $25.0 Total $611.0k $1080.7k

In addition, a number of infrastructure-improvement requests could not be satisfied:

Table K.8 Infrastructure Requests not Funded within the PRL FY 2007 M&S Labor Obs-wide video commun. systems upgrades $170.0 CV and GB voicemail $150.0 CV Edgemont Road cell-phone repeater $25.0 NTC Electronic Lock System $25.0 NTC surveillance system $15.0 NTC two additional offices $20.0 NM VLA ballast and ties $100.0 GBT compressed-air system dryer $10.0 NetApp for GBT control network $50.0 GB Old Jansky Lab switch replacement $8.0 GB Beowulf cluster (pulsar processing,etc.) $25.0 GB Vehicle replacement $35.0 GB site emergency generator $595.0 Total Requests $1228.00k $0.0

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Appendices

A. Scientific Staff Research Activities

Research programs involving NRAO scientific staff research are presented in this appendix.

Cosmology, Large-Scale Structure, Galaxy Formation, and Gravitational Lensing

The GBT and newly commissioned 26–40 GHz receiver with its broadband continuum backend (the Caltech Continuum Backend) will continue to be used to measure 30 GHz flux densities for several thousand point sources in fields observed by other cosmic microwave background (CMB) experiments, particularly the Cosmic Background Imager (CBI). The GBT data will be combined with existing CBI data and new data from the upgraded CBI (with double the collecting area) to yield one of the best measurements of small-scale (l > 2000) CMB anisotropies.

The GBT will be used to study the polarization properties of CMB foregrounds at frequencies ranging from 8 to 43 GHz. Objects of study currently are known clouds with anomalous microwave emission (“spinning dust”) and a flux-limited sample of discrete point sources. While foregrounds do not appear to contribute significantly to results from the current generation of CMB polarization experiments, they will inevitably be a significant confounding factor for future attempts to measure the signatures of primordial gravity waves and gravitational lensing and therefore must be understood.

In collaboration with University groups, the CBI will be used to measure the temperature and polarization angular power spectrum of the CMB as well as to measure the Sunyaev-Zeldovich Effect (SZE) in clusters of galaxies, from the ALMA site in Atacama, Chile.

Astronomers from the NRAO, the Center for Astrophysics, and the MPIfR have begun a large program, the Megamaser Cosmology Project, to measure the current expansion rate of the universe H0 to 3% accuracy by purely geometrical means, providing a test of the Concordance Cosmology and improving our understanding of dark energy. Dark energy (DE) accounts for 74% of the universe by mass, but its nature remains a mystery to physicists and astronomers. It is detectable only through its antigravity effects—accelerating the expansion of the universe and retarding the formation of large-scale structure. To constrain the DE equation of state, the most important complement to existing CMB data is an accurate measurement of H0. The program will reach its goal by using the GBT to discover ten or more circumnuclear H2O masers in distant (D ~ 100 Mpc) Seyfert galaxies, determine their orbital velocities, and monitor their accelerations. The high-sensitivity array consisting of the VLBA, the GBT, and the Effelsberg 100 m telescope will image the circumnuclear disks, and distances to these disks will be calculated by the methods already used to measure the distance to the nearby galaxy NGC 4258.

Observations of the Sunyaev-Zeldovich effect with the CBI and other instruments, X-ray observations by Chandra and XMM, and radio observations using the VLA and ATCA will be combined for a subsample of galaxy clusters in order to constrain cosmological parameters and the astrophysics of the intra-cluster medium.

In the coming year the NRAO scientists will participate in the study of the first galaxies and AGN at radio wavelengths, as well as preparing for the study of the HI 21 cm signal from cosmic reionization, using low-frequency radio telescopes. These studies include using the VLA, GBT, VLBA, IRAM interferometer, and APEX, to study the cold gas, dust, star formation, and AGN in the host galaxies of z >

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6 QSOs from the SDSS, and in Lyα-emitting galaxies from the COSMOS survey. The PAPER project is also being designed to study the HI 21 cm signal from the neutral inter-galactic medium (IGM) during cosmic reionization at z = 6 to 10.

The radio-emitting population of the nearby Coma cluster at λ = 20 cm will be investigated with the VLA. Deep uniform-sensitivity images of the cluster core and an important infall region will be developed from mosaics of VLA pointings. In conjunction with a multi-wavelength program using numerous ground and space-based observatories, these will probe galaxy activity down to even small levels of star formation in dwarf galaxies. The result will be a more complete understanding of galaxy evolution in the environment of this famous galaxy cluster.

The VLA will continue to probe the structure of a new HI cloud complex in the Virgo Cluster that was discovered in the ALFALFA survey at the Arecibo Observatory. The morphologies and kinematics of the VLA detections place important constraints on the masses, orbits, and origins of the clouds, providing insight into the nature of these putative “dark galaxy” candidates.

The GBT Ka-band receiver will be used to complete a blind survey for millimeter-wave absorption towards a radio-selected complete sample of 107 sources. Data for the first half of this project, a GBT Q- band survey of the same 107 sources, have already been obtained. The full survey will be sensitive to molecular absorbers in the redshift range 0.9 < z < 2.4. It will be the first entirely unbiased survey for molecular absorption and should result in a significant increase in the number of redshifted molecular absorbers. It will, for the first time, allow estimates of the probability of finding a molecular absorber per unit redshift interval and the cosmological mass density of molecular gas in the above redshift range. Any detected systems will be followed up in HI λ = 21 cm and OH absorption for the dual purposes of studying physical and chemical conditions in the absorber and measuring changes in fundamental constants.

The GBT and the GMRT will be used to carry out deep searches for redshifted HI λ = 21 cm absorption in high-redshift damped Lyα systems and intermediate-redshift strong MgII absorbers. In parallel, the WHT, VLT, and Gemini optical telescopes will be used to complete a survey for damped Lyα absorption towards a radio-selected quasar sample, to obtain new targets for follow-up λ = 21 cm absorption spectroscopy. This is a long-term program to elucidate the nature of damped absorbers, the precursors of present-day galaxies, and thus probe galaxy evolution. Besides studies of galaxy evolution, the observations will yield a sample of high-redshift λ = 21 cm absorbers that will be followed up with high- resolution Keck-HIRES or VLT-UVES spectroscopy to measure changes in the fine-structure constant and the electron-proton mass ratio.

The Arecibo telescope and the GMRT will be used to obtain high-resolution spectra in the redshifted OH 1720 and 1612 MHz lines from the z ~ 0.25 source PKS 1413+135. The conjugate nature of the satellite OH lines, implying that they arise in the same gas, will allow us to use these high-precision redshift measurements to measure any evolution in the fine-structure constant and the electron-proton mass ratio over a large look-back time. Our present WSRT data (~150 hours of time) show evidence for evolution at the 2.5-sigma level. The planned observations will either confirm the change, thus probing new and fundamental physics, or it will obtain the strongest constraints on changes in the above constants.

The GBT will be used to obtain deep spectra in the redshifted CCH 1–0 lines from the z ~ 0.885 gravitational lens towards PKS 1830−210 in an attempt to use these lines to probe fundamental constant evolution over cosmological time. In parallel, the molecular structure of CCH will be analyzed to obtain the precise dependences of the different transition frequencies on the fine-structure constant and the electron-proton mass ratio.

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Deep GMRT 327 MHz observations of the Chandra Deep Field (South) will be analyzed. When combined with a present ATCA L-band image, this will allow the detection of ultra-steep-spectrum sources in this field down to an L-band flux density of ~ 75 microJy, far below current flux-density thresholds. These sources are believed to be the best candidates for the highest-redshift radio galaxies; the observations will thus determine whether a hitherto undetected population of faint radio galaxies exists at high redshifts.

The ATCA will be used to search for CO 3–2 emission from a damped-Lyα system at z ~ 2.347, following up on our tentative detection of CO emission from this system. If confirmed, this will be the first detection of molecular emission from a normal galaxy at high redshift.

A possible detection of intergalactic scattering will be pursued. We have a tentative detection of angular broadening due to the intergalactic medium (IGM). This detection arises from a 16-day 5 GHz VLA survey of 482 compact, bright (S > 105 mJy at 8.5 GHz) radio sources for intra-day variability (the Micro-Arcsecond Scintillation-Induced Variability “MASIV” survey). This survey shows that the numbers of variable and non-variable sources are roughly equal for z < 2.5, but only two out of 14 objects exhibit intra-day variability (IDV) at z > 3. One possible explanation for this redshift-dependence of IDV is that angular broadening caused by scattering in the IGM makes high-redshift sources too large to exhibit interstellar scintillation. For a source at a sufficiently high redshift both the IGM density, proportional to (1+z)3, and the large total path length cause enough angular broadening that all high- redshift sources fail the stringent angular size requirements (<10–100 microarcsec) to exhibit IDV due to our Galaxy's interstellar medium. We will attempt to confirm this detection by optical followup of the remaining 300 sources in our sample and by targeted searches for radio IDV of a sample of known high-z compact quasars. If confirmed, this detection would constitute a measurement of intergalactic turbulence on a scale of only 1010 meters and provide a direct measurement of the energy injected into the IGM (i.e. by galaxy feedback mechanisms).

The VLA will be used to make a deep observation of the Mitchell-Condon field at about 320 MHz with a resolution of ~5 arcsec. Spectral indices will be determined by comparison with 1.4 GHz images. Optical multi-band images of the entire field have been obtained with the CFHT. The aim is to detect unusual objects for further study.

Work will continue on the deep SWIRE field, 1046+59. The λ = 90 cm VLA survey of the field, which is the deepest ever made at that wavelength, will be completed. Together with the λ = 20 cm data and a deep GMRT survey at λ = 50 cm, these data will be used to define the low-frequency radio spectra of the microJy source population. A confusion-limited Spitzer survey will also be completed late in this period. It will be used, among other things, to understand the radio/FIR correlation at high redshift. Further imaging in the near infrared with the CFHT and the GMRT will occur during this period. These data will be used to improve the photometric redshifts and our understanding of the evolving spectral energy distributions (SEDs) of distant galaxies in this field.

A multi-wavelength follow-up program will continue on the COSMOS HST Treasury field using the 1/4 square-degree deep survey at λ = 1.1 mm with Bolocam and the deeper 1/8 square-degree survey at λ = 1.2 mm with MAMBO. Combined, these surveys have produced a candidate list of ~50 ultraluminous high-redshift dust-enshrouded starbursts and AGN (“submillimeter galaxies”). A recent deeper VLA λ = 21 cm image of the field, as well as Cycle-2 Spitzer IRAC and Cycle-3 MIPS observations will be included in the on-going analysis to provide improved information on the luminosities, redshift distribution, and SEDs of these galaxies. In addition, new observations, including λ = 350 µm photometry (CSO/SHARC-2) and optical spectroscopy (VLT-VIMOS and Keck-DEIMOS) spectroscopy

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will be undertaken, and CO spectroscopy using the GBT and a new diffraction grating spectrometer at the CSO (see Instrumentation below) will be proposed.

The VLA and VLBA will be used to carry out follow-up observations of candidate gravitational-lens systems discovered in the Cosmic Lens All-Sky Survey (CLASS) and to study the properties of the lensing galaxies such as the dark-matter distribution in their cores. Observations are being undertaken to use the VLBA to find and/or place limits on the existence of so-called “core images” in lens systems, a sensitive test of the gravitational potential in the lensing-galaxy core.

The propagation of gravitational radiation subject to gravitational lensing will be investigated with respect to the emission expected from various radiation sources (e.g. merging neutron-star binaries and black- hole binaries). Various operational and planned detectors will be able to detect these sources out to significant redshifts, so the radiation from these sources is particularly susceptible to gravitational lensing by small-scale structures that can randomly amplify or de-amplify the signals. It has recently been suggested that merging black-hole systems may be used as “standard sirens,” whereby the rate at which the emission frequency changes (as the system merges) can be used to determine the intrinsic luminosity of the source. Gravitational lensing by small-scale structure, however, alters the observed intensity of the signal, thus affecting our ability to use these sources as standard sirens.

Radio Galaxies, Quasars, Active Galaxies, and Gamma-Ray Bursts

In 2006 the VLBA Imaging and Polarimetry Survey (VIPS) got under way with the first-epoch observations at 5 GHz. As of mid-July 2006, 702 of 1127 sources had been observed, and the images of all can be found on the public VIPS web page. Many intriguing new sources, including several candidate supermassive binary black-hole systems, have been discovered in the survey and will be targeted for follow-up. VIPS forms a well-defined statistically complete sample of compact radio sources that are likely to be detected by the Gamma Ray Large Area Space Telescope (GLAST) following its launch in late 2007. VLBI imaging, which resolves the jets associated with the gamma-ray radiation, is critical for maximizing the scientific return from GLAST. In FY 2007 the VIPS observations will be completed, and papers will be submitted describing the radio and optical observations of the VIPS sample. The data bases from VIPS thus will be available by the time of GLAST launch in late FY 2007 or early FY 2008.

Studies of the physics of relativistic large-scale (kiloparsec) jets in active galaxies are being actively pursued. The Spitzer Space Telescope (infrared) joins the Chandra X-ray Observatory, Hubble Space Telescope (optical), and Very Large Array in a multi-band approach to study their emission properties. Detailed images from these observatories are being obtained and analyzed along with a new systematic Spitzer infrared study of powerful quasar jets including the famous 3C 273.

Observations of total intensity and polarization will continue with the VLBA to determine the collimation and acceleration of the relativistic flows in quasar and AGN jets, to better define the distribution of intrinsic Lorentz factors, brightness temperature, luminosity, and Doppler factors as well as the role played by magnetic fields. Particular attention will be paid to the nearby jet in M87 which is resolved in the transverse direction as well as the more powerful jets in the quasars CTA 102 and 3C 454.3. This program is an extension of observations begun in 1994 and will extend into the GLAST era to give new insights into the nature of gamma-ray emission from AGN.

The highest-redshift (z ~ 4) relativistic jets are being studied with the VLA and VLBA, together with Chandra imaging of emission on scales of tens to hundreds of kiloparsecs. Multi-frequency studies of their radiation on large scales will help test emission models that will constrain fundamental physical

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parameters (magnetic fields, electron energy distributions) of these early, actively accreting supermassive black-hole systems.

High-quality VLA imaging and polarimetry of the radio jets in several FRI radio galaxies will be combined with Chandra and XMM imaging to elucidate the dynamical parameters of the jet outflows as functions of distance from the AGN, to explore the jet-gas interactions that control kiloparsec-scale jet collimation and deceleration in these outflows, and to identify the sites (and hence constrain the mechanisms) of relativistic-particle acceleration within them. Multifrequency polarimetry of FRI radio galaxies and X-ray data on their hot gaseous environs will be used to examine the spatial statistics of the magnetoionic media around the galaxies and to derive the spectrum of the magnetic-field fluctuations in hot gas associated with the surrounding groups.

Continued multi-wavelength monitoring of the well-known jet in M87 (Virgo A) are being pursued with Chandra, HST, VLA, and VLBA. Dramatic variability has been observed in the jet, and continued monitoring of its X-ray/optical/radio light curves and a detailed kinematical study of the relativistic ejections resolved with the VLBA give important constraints on the physics of very high energy particle acceleration and energy-loss mechanisms in AGN jets.

The VLBA will continue being used to study the dynamics of the base of the jet in M87. At 43 GHz, the VLBA apparently just resolves the collimation region of the jet and is able to resolve side-to-side structures only a short distance farther out. As a result of its relative proximity, high flux density, and high-mass black hole, M87 is the best source for such a study of a jet on small enough scales relative to the gravitational radius of the central black hole. During 2006 the VLBA was used to determine roughly the rates of motion of features close to the core in order to determine an appropriate frame rate for a movie. It is likely that previous observations have been seriously undersampled. Initial analysis suggests that the motions are subluminal and a frame rate of weeks to months will be appropriate, but the observations and processing need to be completed. It is expected that the actual movie observations will begin in early 2007.

A project comparing the radio and X-ray properties of the jet in the nearby elliptical galaxy NGC 315 is in the final stages. The imaging of IC 1262, an object with interesting similarities to M87, will also be completed with the VLA (at λ = 20 and λ = 90 cm) and Chandra. Work will continue on the difficult low- frequency imaging projects of Cen A and M87.

Work continues on the counterjet found in 3C 84 (NGC 1275). Multiband VLBI data showed that the counterjet is strongly free-free absorbed: it is much weaker at low frequencies than at high frequencies and its spectrum matches that of free-free absorption. The fact that this absorption does not affect the main jet, which is presumably on the near side of the accretion disk, shows that the absorption is the result of ionized gas associated with the accretion disk. It could be the disk itself, an atmosphere, or a wind. An analysis of more recent multi-band data is ongoing to look for changes in the absorbing screen.

VLBA monitoring of the relatively nearby superluminal source 3C 120 continues to provide interesting constraints on jet physics. This jet is seen at radio, optical, and X-ray frequencies. In the radio it can be studied over a very wide range of scales. Previous theoretical analyses of helical instabilities in the inner few parsecs of the jet, and an analysis of the implications of X-ray detections of features on kiloparsec scales, have provided constraints on the physical properties of the jet. The current work includes an attempt to determine the structure of the jet in the transition region between parsec and kiloparsec scales using a very long integration at 327 MHz with the VLBA. Among other results, the image shows an intriguing knot at 4 arcsec (2 kpc) from the AGN with more detail than previously available. That knot corresponds to an optical knot in a structure that crosses the jet at that point. It has also been shown to be

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much more slowly moving than the underlying superluminal jet. In addition to the 327 MHz observation, the long-term monitoring effort at 1.6 GHz with the VLBA continues with an observation every two years.

Studies of X-shaped radio galaxies—extragalactic radio sources with an additional pairs of lobes—are being pursued. Such objects are rare (about a dozen are known) and have been attributed to remnants of a merger in a binary supermassive black-hole system. A new sample of about 100 sources has been compiled utilizing the FIRST database. Imaging with the VLA and other observatories is being pursued to test formation models.

Observations having higher sensitivity and angular resolution will be made of the Seyfert 1 nucleus of NGC 4395, using the VLBI High Sensitivity Array (HSA). The nucleus of NGC 4395 is energized by a black hole of 360,000 solar masses, making it one of only two nuclear black holes of intermediate mass (one thousand to one million solar masses) detected in the radio regime. Building upon UV and X-ray evidence for outflows from this Seyfert nucleus, the HSA was used at 1.4 GHz to search for extended structure on scales greater than 5 milliarcsec (0.1 pc). Elongated emission was discovered extending over 15 milliarcsec (0.3 pc) and suggesting an outflow on sub-parsec scales from this intermediate-mass black hole. The Seyfert nucleus is located at the center of an elliptical star cluster, and the elongation position angle of the sub-parsec radio structure is only 19 degrees from the star cluster's minor axis. The new observations are expected to strengthen the case for an outflow and to assess the kinematic impact of the outflow on the environs of the Seyfert 1 nucleus.

New VLBA observations of Mrk 231 at 15, 22, and 43 GHz will be used to test competing models for the broad absorption line (BAL) outflows (equatorial winds or a bipolar outflow). Generally, these models cannot be directly tested because structures inside the nominal 1-pc sublimation radius of the molecular gas in BAL QSOs cannot be resolved. However, Mrk 231 is the nearest BAL QSO, so the VLBA's sub- milliarcsec resolution can trace the geometry of the central engine. Our imaging goals are to search for substructure in the outflow, refine understanding of the role of free-free absorption toward the outflow, and improve constraints on the slow proper motions in the outflow.

Studies of the radio and X-ray signatures of low-luminosity active galactic nuclei (LLAGN) will continue in the weakest accreting massive black holes. Our detections of these LLAGN reveal that they have very low Eddington ratios and are radio loud. Such traits emphasize the potential importance of radio outflows from these modest-mass black holes, mainly hosted by disk galaxies. We have augmented these results by recently observing three nearby elliptical galaxies, for which the black-hole masses are typically larger and radiatively inefficient accretion fed by hot gas is expected. Archival Chandra data for the trio indeed show candidate LLAGN with extremely low Eddington ratios. Two elliptical galaxies are sub-mJy sources at 8.5 GHz with size upper limits of 2 arcsec and 9 arcsec; their new VLA images at subarcsecond resolution will be used to assess radio structure, variability, and spectral indices, as well as to examine radio-loudness at matched Chandra/VLA resolutions. The new VLA image of the third elliptical will be used to search for a counterpart to the candidate X-ray nucleus, to bolster the case that a true LLAGN has been identified: if the candidate X-ray nucleus is radio loud, we expect it to be 57 microJy or stronger near 8.5 GHz. Image analysis has begun, with publication likely early in the reporting period.

The extremely bright emission from several IDV radio quasars will be investigated. A particular aspect of this ongoing work is the measurement of changes in the micro-arcsecond structures of these sources using the technique of Earth Orbital Synthesis (EOS), whereby the Earth's changing velocity with respect to the interstellar scattering medium responsible for the variations can be used to build a two-dimensional microarcsecond “image” of the source. A particular application of this to the intra-hour variable quasar J1819+3845 will be pursued. Here, observations taken at exactly the same epoch each year are compared

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to reconstruct changes in the source structure. The differences in the power spectra of light curves taken exactly a year apart reflect changes in the underlying structure (viz. changes in the power spectrum of the source brightness distribution).

A complete sample of all 2MASS galaxies brighter than Ks = 12.5 detected by the 1.4 GHz NVSS is being constructed to study radio continuum emission from normal galaxies. This sample includes several thousand radio sources powered by AGN and is large enough to determine an accurate radio luminosity function of AGN for the first time. The sample also includes several thousand radio sources in star- forming galaxies. The radio luminosity of each is proportional to the recent star-formation rate, and the near-infrared luminosity is proportional to the total stellar mass, so the radio/infrared flux ratio is a good measure of the star-formation rate per unit mass.

The VLA Low-frequency Sky Survey (VLSS) is a sky survey made with the VLA at 4 meters wavelength by collaboration between the NRAO and the Naval Research Laboratory. Observations in the current B and AnB configurations should substantially finish this survey. The latest results are available on the Web.

VLA observations of the Chandra Deep Field South at λ = 6 cm and λ = 20 cm suggest that the microJansky source population is more dominated by AGN rather than starburst activity than previously thought. New λ = 6 cm VLA observations with a resolution of only 0.4 arcsec will confirm the AGN nature of the weak radio-source population.

The VLA will observe a complete sample of radio sources stronger than 0.3 Jy at 8 GHz in order to determine their milliarcsecond structures. This sample, including all radio spectra, will be used to investigate the compactness properties of extragalactic sources.

The VLA will be used to observe a complete sample of flat-spectrum radio sources chosen at 30 GHz and stronger than 5 mJy in order to determine the angular-size distribution of a high-frequency sample. The nature of the structures in a high-frequency sample of radio sources is at present unknown.

The nature of a new population of very large FRI galaxies will be studied using a sample of radio galaxies selected from the Bologna B2 sky survey and existing low-resolution VLA images.

High-resolution imaging of three cluster-core radio galaxies (Abell 2029, 2052, and 2199) will be λ = 20 and λ = 90cm using the VLA and the Pie Town VLBA antenna. These data should produce higher fidelity and spatial resolution for these nearby systems than has been available previously for comparison with the existing Chandra images.

VLA and Chandra data will be combined to extend the radio/X-ray correlation observed in stellar-mass black holes) to low-mass active galactic nuclei, to probe similar physics over six to eight orders of magnitude in mass.

The GBT will be used for formaldehyde densitometry of external galaxies. Studies of the distribution of CO emission in external galaxies have pointed to the presence of large quantities of dense molecular material in these objects. These studies have yielded a detailed picture of the molecular mass in many external galaxies. But because the CO emission from external galaxies is dominated by radiative-transfer effects such as high optical depth, it is not a reliable monitor of the physical conditions such as spatial density and kinetic temperature that affect star formation in these regions. Emission from less-abundant, higher-dipole-moment molecules is better suited to the task of deriving the spatial density and kinetic

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temperature of the dense gas in external galaxies. For this reason, emission-line studies of molecules such as CS, HCN, HCO+, HC3N, and NH3 are being made toward a variety of mainly nearby galaxies.

The most extensive sets of measurements of the molecular line emission in external galaxies are based on 4 -3 CO and HCN. Since CO and HCN are good tracers of dense gas [n(H2) > 10 cm ] but do not provide specific information about the physical conditions in these regions, a molecule which allows for a simpler interpretation of its emission is required. Formaldehyde (H2CO) has proven to be a reliable density and kinetic-temperature probe in Galactic molecular clouds. Using the unique density selectivity of the K- doublet transitions of H2CO, the GBT will be used to measure the dense-gas structure and spatial density in a sample of nearby and luminous galaxies.

The VLA will continue to be involved in a long-standing program to study the radio afterglows from gamma-ray bursts (GRBs). This is part of a large multi-wavelength effort at gamma-ray, X-ray, infrared, submillimeter, and centimeter wavelengths. The emphasis will be on events giving the highest science return: rare bright events, short-hard bursts, and high-redshift (z > 6) events. A related program at the CSO will continue with the aim of detecting GRB afterglow emission at λ = 1.1 mm with Bolocam for the purpose of providing new constraints on total burst energies and the density structure of the circumburst medium.

Continued multi-wavelength monitoring of the well-known jet in M87 (Virgo A) is being pursued with Chandra, the HST, the VLA, and the VLBA. Dramatic variability has been observed in the jet. Continued monitoring of the X-ray/optical/radio light curves and a detailed kinematical study of the relativistic ejections resolved with the VLBA give important constraints on the physics of very-high-energy particle acceleration and energy-loss mechanisms in the AGN jet.

The VLBA will continue being used to study the dynamics of the base of the jet in M87. At 43 GHz (λ = 7 mm) the VLBA apparently just resolves the collimation region of the jet and is able to resolve side-to- side structures only a short distance farther out. As a result of its relative proximity, high flux density, and high-mass black hole, M87 is the best source for such a study of jets on small-enough scales relative to the gravitational radius of the central black hole. During 2006 the VLBA was used to determine roughly the rates of motion of features close to the core in order to determine an appropriate frame rate for a movie. It is likely that previous observations have been seriously undersampled. Initial analysis suggests that the motions are subluminal and a frame rate of weeks to months will be appropriate, but the observations and processing needs to be completed. It is expected that the actual movie observations will begin in early 2007.

A project comparing the radio and X-ray properties of the jet in the nearby elliptical galaxy NGC 315 is in the final stages. The imaging of IC 1262, an object with interesting similarities to M87, will also be completed with the VLA (at λ = 20 and 90 cm) and Chandra. Work will continue on the difficult low- frequency imaging projects of Cen A and M87.

A complete sample of all 2MASS galaxies brighter than Ks = 12.5 detected by the 1.4 GHz NVSS is being constructed to study radio continuum emission from normal galaxies. This sample includes several thousand radio sources powered by active galactic nuclei and is large enough to determine an accurate radio luminosity function of AGN for the first time. The sample also includes several thousand radio sources in star-forming galaxies. The radio luminosity of each galaxy is proportional to the recent star- formation rate and the near-infrared luminosity is proportional to the total stellar mass, so the radio/near- infrared flux ratio is a good measure of the star-formation rate per unit mass.

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The Very low frequency VLA Sky Survey (VLSS) made with the VLA at 4 meters wavelength is being performed by collaboration between the NRAO and the Naval Research Laboratory. Observations in the current B and AnB configuration should substantially finish this survey. Current results are available on the Web.

VLA observations of the Chandra Deep Field South at 6 and 20 cm wavelengths suggest that the microJansky source population is more dominated by AGN than by starburst activity than previously thought. New λ = 6 cm VLA observations with a resolution of only 0.4 arcsec will confirm the AGN nature of the weak radio sources.

The VLA will observe a complete sample of radio sources stronger than S = 0.3 Jy at 8 GHz in order to determine their milliarcsecond structures. This unbiased sample, selected regardless of radio spectrum, will be used to investigate the compactness properties of extragalactic sources.

The VLA will be used to observe a complete sample of flat-spectrum radio sources stronger than 5 mJy at 30 GHz in order to determine the angular-size distribution of a high-frequency sample. The nature of the radio structures in a high-frequency sample of radio sources is at present unknown. The nature of a new population of very large FRI galaxies will be studied using a sample of B2 radio galaxies and existing low-resolution VLA images.

The high-resolution imaging of three cluster-core radio galaxies (Abell 2029, 2052, and 2199) will be completed at λ = 20 cm and λ = 90 cm using the VLA plus the Pie Town VLBA antenna. These data should produce higher fidelity and spatial resolution for these nearby systems than has been available previously for comparison with the existing Chandra images.

Normal Galaxies

The VLA will be used to measure the kinematics of spiral galaxies beyond their optical disks using neutral hydrogen. The kinematics will be combined with Hα imaging spectroscopy from the Robert Stobie Spectrograph on the South African Large Telescope to produce multi-scale multi-wavelength velocity fields of the highest quality for a large sample of nearby spirals. These systems will be used to study the impact of baryons on the dynamics of disk galaxies, in an effort to understand the nature of long-standing discrepancies between Cold Dark Matter Paradigm predictions and observations on galaxy scales.

The VLA will be used to study the kinematics of hydrogen-deficient galaxies in the periphery of the Virgo cluster by probing their HI emission with unprecedented resolution and sensitivity. The observations will elucidate what physical processes play a role on the HI deficiency of galaxies inhabiting the suburbs of clusters, thus providing further insight into the connection between the properties of galaxies and their environments.

The VLA has been used to obtain maps of the HI distributions in nine spiral galaxies. All were presumed to be isolated objects, but the HI maps reveal that one has a nearby companion and two others are undergoing minor mergers with smaller galaxies. The remaining six are indeed isolated, and an analysis of the maps is in progress in order to examine the cause of the asymmetric integrated HI profiles in some of the objects and to search for faint HI clouds that might be associated with the galaxies.

The connection between spiral-galaxy kinematics and the HI line width–absolute magnitude (Tully- Fisher) relationship will continue to be studied using GBT and VLA data. A galaxy model has been constructed for synthesizing HI line profiles and HI maps from galaxy rotation curves, HI distributions,

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and other parameters for a PhD thesis under the direction of the NRAO staff. Comparisons between VLA maps and model-synthesized HI maps are providing useful insights into the galaxy characteristics that affect HI profile widths.

A study of the kinematics and morphologies of peculiar Virgo Cluster galaxies is continuing, including objects with evidence of tidal interactions and mergers. A similar study on Fornax cluster galaxies is underway using data from the ASTE telescope at Chajnantor. A study of the distances to 11 peculiar galaxies in Virgo using Tully-Fisher determinations based on stellar kinematics is nearing completion. One of the aims of this investigation is to test controversial results on the in-depth structure of the cluster.

An ongoing investigation of the chemical-enrichment history of local dwarf galaxies will continue. Using multi-slit spectroscopy, a new metallicity calibration of the Ca II triplet in red-giant stars has been completed. Application to the SMC field reveals that star formation went through an initial burst ≥ 10 Gyr ago, then through a quiescent period, and then peaked again some 3 ± 1 Gyr ago. The star formation rate dropped about 1 Gyr ago. These results are being readied for publication. A similar method will be applied to the Fornax dwarf spheroidal galaxy.

Recently discovered strong chemical differentiation in galactic nuclei suggests that the chemical and physical states of the ISM in the centers of galaxies are strongly variable. Such morphological variations provide a potentially powerful method of tracing the evolution of the ISM in external galaxies. The VLA, PdBI, OVRO, and BIMA arrays will be used to map at arcsecond resolution the distributions of astrochemically important molecules in the nuclei of nearby gas-rich galaxies, including Maffei 2, M82, M51, and NGC 1068. Imaging of species including HCN, CS, HCO+, CN, C2H, HNCO, HNC, HC3N, 34 N2H+, C S, SiO, CH3OH and C-C3H2 will be used to investigate the impact of star-formation strength, evolutionary state, and galactic structure on the chemistry of the nuclear ISM. The dense-gas tracers HCN, CS, and HC3N will be used to generate an inventory of massive dense cores across the nucleus of these galaxies. Photodissociation-region tracers such as CN and C2H will be used to delineate massive- star formation/molecular-gas interaction sites, while shock tracers such as CH3OH and SiO will be used to map the locations and strengths of shocks induced by galaxy dynamics.

Full IRS mapping (5 µm–40 µm) of the inner bulge region of two nearby large spiral galaxies (IC 342 and Maffei II) will be obtained with the Spitzer Space Telescope. Maps of mid-infrared features including emission from gas-phase PAHs (λ = 6.2, 7.7, 8.6 and 11.2 µm) and various fine-structure atomic lines, absorption from grain silicates (λ = 9.7 µm), and ice-mantle chemical species (including H2O, CO2, CH4, and HACs) will be used to resolve changes in dust properties across these starburst nuclei. The dust properties will be compared with existing maps of important gas-phase molecules to provide the first investigation of the interconnection between dust and gas chemistry over large regions of the nuclei of spiral galaxies. Of particular interest will be (1) the correlation between mid-infrared PAH features and gas-phase photodissociation tracers (simple hydrocarbons), and (2) searches for ice-mantle evaporation towards bar/spiral arms regions where gas-phase observations of CH3OH trace shock-induced grain mantle evaporation.

The VLA will be used to search for radio emission from G1, a globular cluster in the nearby Andromeda galaxy whose dynamics indicate that it may contain an intermediate-mass black hole of about 20,000 solar masses. If so, this may be the nearest version of the intermediate-mass holes found in a number of nearby low-luminosity active and inactive galaxies. The possible existence of massive black holes at the centers of globular clusters is of interest because of the relation to ultra-luminous X-ray sources in star- forming galaxies and the global relation between galaxies and black hole masses that has been found in recent years. An important discriminator between a collection of stellar-mass black holes in binary systems and a single massive black hole is the relation between X-ray and radio luminosities. These

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observations will be used to compare the limits/detections of X-ray and radio emission for those of stellar- mass and intermediate-mass black holes, and test the inference that G1 contains a 20,000 solar mass black hole.

VLA studies of ultraluminous X-ray sources (ULXs), based on both new and archival data, should help constrain their physical nature. These enigmatic objects are unresolved with Chandra and are often variable, suggesting that they are intrinsically very small, but they are significantly offset from galaxy nuclei, and their X-ray luminosities exceed the Eddington limit for accretion onto stellar-mass compact objects. The two most popular explanations are relativistic beaming from stellar-mass sources, which would imply a huge number of sources, and isotropic emission from intermediate-mass black holes, which would require some previously unsuspected mechanism to make such beasts. Radio observations have found no clear point-like counterparts but do in some cases show extended (hundreds of parsecs) emission near the ULXs. The latter in particular is interesting, as it would tend to support the isotropic model and provide important constraints on the longevity of the ULX emission. Current studies are based primarily on single-frequency observations of a handful of oddly selected ULXs; the VLA studies will extend this to more frequencies (to define the radio emission mechanism) and to a more uniform sample.

VLBI imaging of the nearby merger system Arp 299 has taken place over several years, using the VLBA plus the GBT. This imaging is being used in a search for young supernova remnants resulting from the starburst in the merger. As many as 15 such objects have been detected in the nuclei of the two merging galaxies, indicating the formation of a number of super star clusters in the merger. In the upcoming year, the final data analysis will be done, and the supernova rate and luminosity function will be derived for the merger.

Similar VLBA+GBT observations of the nearest merger pair, the “Antennae,” will take place in late FY 2006 and will be analyzed in FY 2007. It is expected that the 30 hours of scheduled observations for this merger, at a distance of 20 Mpc, will enable detection of young supernovae with luminosities as small as 10 times that of Cas A. Given the approximate supernova rate in the Antennae, it is anticipated that 10– 15 young supernovae will be detected at this luminosity threshold. Since the regions of significant radio emission and star formation in the Antennae are spread over more than an arcminute and must be imaged at milliarcsecond resolution, a rather challenging imaging problem is expected.

The Interstellar Medium, Molecular Clouds, Cosmic Masers, Star Formation, and Stellar Evolution

The GBT will be used to map high-latitude Galactic HI fields in the λ = 21 cm line to look for correlations with observations taken in the far infrared (FIR). In the Galaxy a tight correlation exists between the total amount of gas and the total amount of dust as measured in FIR emission. The correlation coefficient, however, can show some variation among different components of an HI spectrum in a single direction. Preliminary investigations indicate that the FIR/HI ratio and its variation across the FIR bands is a sensitive indicator of the composition of interstellar dust, and in one case it reveals evidence for shock processing of grains in an HI line which appears otherwise normal. This opens up the possibility that through these studies we might untangle some of the confusion in blended interstellar lines and gain insight into the ISM that is not available from either the HI or the FIR data by themselves. Needless to say, this line of investigation is relevant to the issue of foregrounds in studies of the cosmic microwave background radiation, and some of the work will be directed towards parts of the sky that will be observed in future cosmological missions such as Planck.

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The GBT will be used to study the disk-halo interface in the Galaxy by measuring the λ = 21 cm line from the long vertical whiskers of HI that have been discovered from preliminary observations to be rising out of the plane in the inner Galaxy. It is possible that these whiskers are the walls of old superbubbles, or regions where clusters of supernova remnants have blown out the disk gas and vented directly into the halo. The GBT studies of large areas will be combined with more limited data from the VLA and Arecibo to measure the spectrum of angular sizes of halo clouds and their connection into larger structures.

A large-area survey (~90 square degrees) of the northern Galactic Plane in λ = 1.1 mm dust continuum using Bolocam at the CSO will be completed. This survey also includes λ = 350 µm mapping of selected sub-regions. The data reduction, already in progress, will be completed with the eventual goal of making the survey maps publicly available. The catalog of molecular cores, which are expected to include a substantial fraction of pre- and proto-stellar objects (within ± 105 years of stellar ignition), will be published. This survey will be compared with existing Galactic Plane surveys, including the VLA Galactic Plane survey, Spitzer-GLIMPSE, and the BU-FCRAO 13CO Ring survey. The sample of new pre- and proto-stellar cores will also be followed up with molecular spectroscopy from both the VLA and the GBT to provide detailed information on the temperature and density conditions within the cores.

A project is underway to survey 110 square degrees of the northern Galactic plane covered by the GLIMPSE Spitzer Legacy program and a deep near-IR survey by the UK IR Deep Sky Survey consortium using the VLA at 6 cm wavelength in the “B” configuration. These data should help distinguish between radio-loud ultra-compact HII regions and radio-quiet massive young stellar objects. Results of this survey will be released as they become available.

The discovery of thousands of dense clouds opaque at λ = 8 µm by the MSX and the Spitzer GLIMPSE survey suggests that infrared dark clouds (IRDCs) may represent the earliest observable phases of massive-star formation. These clouds exhibit structure on all spatial scales, and observations using the combination of the GBT and VLA will be used to investigate a sample of IRDCs to probe their morphologies, physical properties, chemistry, and kinematics. The transitions of the key molecules CCS and ammonia at 23 GHz being used in this study also have the potential to establish chemical ages for the IRDCs and will enable direct comparisons with nearby low-mass pre-protostellar cores. The GBT and VLA will also be used to search for other tracers of active star formation, such as 8 GHz continuum emission and water masers, to enable the cloud properties to be correlated with star-formation activity.

Turbulence and Galactic magnetism in the warm interstellar medium of the Milky Way will be studied using radio-polarimetric observations from the Australia Telescope Compact Array and Parkes single- dish telescope. These observations in the Galactic plane, along a Galactic meridian and in low-emission high-latitude regions, will yield a wide range of science results such as characterization of turbulence in the interstellar gas, strength and structure of the large-scale Galactic magnetic field through modeling, estimates of the synchrotron foreground emission for CMB polarization studies, and the role of magnetism in supernova-remnant evolution.

GBT and VLA observations will be combined to provide detailed maps of the structure of high-latitude HI clouds detected in recent GBT surveys. These clouds seem to be well-defined separable systems, and many are unresolved even with sub-arcminute resolution. Such isolated objects are unique probes of the physical conditions as a function of galactic latitude, acting for instance as barometers to measure the local gas pressure.

The VLBI High Sensitivity Array (HSA) will be used to image the small-scale galactic HI structure in the direction of the quasar 3C 147. The VLBA, the GBT, and the phased VLA can image the galactic HI with

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high velocity resolution (0.4 km/s) and high angular resolution (10 milliarcsec or 5 AU). The background quasar has an angular size of about 200 milliarcsec. This project is a continuation of earlier VLBA (plus phased VLA) investigations of the small-scale HI structure in the direction of the larger background source 3C 138; prominent variations in the HI opacities were detected in this sensitive observation.

With the MERLIN array in the U.K., three larger sources (slightly less than about 1 arcsec) are being used to image the galactic small-scale structure with a angular resolution at the 100 milliarcsec level, about a factor of ten larger than the VLBA (plus HSA ) resolution. Again significant fluctuations are being observed in the galactic HI opacities. These two data sets will provide an important contribution to the investigations of the small-scale structures in the components of the interstellar medium from size scales of about 1 AU to several parsecs.

Recent observations of bright southern pulsars have enabled the first measurement of OH absorption towards a pulsar and the discovery of pulsed OH maser emission stimulated by a pulsar. The GBT will be used to search for OH absorption toward bright pulsars in the northern sky. Additionally, OH masers are known to form near supernova remnants where the shock of the supernova explosion has interacted with a nearby molecular cloud. The GBT will be used to find additional examples of pulsar-driven stimulated emission with spectroscopic observations of pulsar–supernova-remnant associations.

The GMRT will be used to obtain deep Galactic HI λ = 21 cm absorption spectra towards a large sample of compact bright radio sources. The observations will be sufficiently sensitive to detect the warm phase of HI in absorption even at temperatures as high as ~8000 K. This will directly test whether a large fraction of the Galactic HI lies in the thermally unstable region (temperatures between about 500 K and 5000 K) as suggested by the single-dish observations of Heiles & Troland.

The WSRT will be used to obtain deep high-resolution Galactic HI λ = 21 cm absorption/emission spectra towards a sample of ten bright high-latitude radio sources. This will test whether a new population of tiny discrete features in the diffuse interstellar medium, presently detected with the WSRT towards four sources, is indeed ubiquitous. Substantial injection of small-scale power into the ISM would be needed if such structures are very common, posing problems for theoretical models. These observations will also obtain the power spectrum of Galactic HI at very low column densities.

The Keck Interferometer will be used to investigate the origin of CO band-head emission from the young stellar object DG Tau. The CO emission traces the hot dense neutral material in the inner regions of circumstellar accretion disks and potentially provides important information about the physical, chemical, and dynamical state of the gas in the region where jet production and accretion take place during the formation of solar-type stars. These measurements aim to determine whether the CO emission originates inside the dust-destruction radius in the disk or from a more extended externally heated surface layer in the disk photosphere. The GBT will be used to directly measure the expansion speed of ultra-compact HII regions (UCHII) using carbon recombination line (CRL) emission between 31 and 35 GHz. Non-LTE models of the CRL emission have been developed to determine the physical properties in these regions. The model results are consistent with the theory that high-density molecular material is inhibiting the expansion of the UCHII region by pressure confinement and therefore explains why the observed UCHII lifetime is longer than the dynamical lifetime, which assumes the gas expands at the sound speed—although other theories cannot be ruled out. The models predict that CRL emission below ~25 GHz is dominated by stimulated emission caused by the background continuum radiation from the UCHII region. Therefore, almost all previous observations have only detected gas in front of the UCHII region. Above 25 GHz CRL emission should be detected both in front of and behind the UCHII region, allowing a direct measurement of the expansion speed.

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Using the submillimeter-wavelength transitions of H2CO, the CSO will be used to study the physical conditions in the warm dense cores of molecular clouds. H2CO is the ideal molecule for this purpose because its numerous submillimeter transitions allow independent temperature and density determination of the emitting gas. The high-excitation transitions in the 650 and 800 GHz windows probably arise from gas that is too warm for depletion to have substantially altered the molecular abundances, and they should probe material quite close to the young star(s) buried in the dense core.

The VLBA will be used in the upcoming year to continue measuring the absolute positions of water masers in the nearby low-mass star-forming region, Rho Ophiuchus. Repeated measurements (twice per month) of the absolute maser positions will allow us to disentangle the parallax, the overall cloud motion, and the peculiar water-maser motions. The parallax measurement will allow an estimate of the distance to the water masers with an accuracy of about 0.5%. Not only will a precise distance lead to the best determination of the luminosities, jet velocities, outflow momenta, and many other physical quantities of this star-forming region, but it will also give a unique opportunity to look at the three-dimensional structure of the cloud and its relationship to the stars in the Upper Scorpius subgroup. The VLBA is the only instrument in the world that has the capability to make this kind of accurate measurement.

The VLBA will be used to continue refining techniques in accurate absolute position measurements at short wavelengths (especially at λ = 1.3 cm using the water-maser line) in order to extend such measurements reported in the previous paragraph to star-forming regions across the Galaxy.

The VLBA will also be used to study magnetic fields in the near-stellar environments of low-mass young stellar objects (within a few tens of A.U.) by using the Zeeman splitting of the water-maser line at 22 GHz. Preliminary results suggest that line-of-sight fields on the order of a few tens of milliGauss can be detected with this technique.

The VLBA will be used to investigate proper motions of OH masers in massive-star-forming regions. Early observations of OH maser motions in the source W3(OH) showed that slow expansion is the dominant kinematic mode. Recent observations of OH masers in ON 1, K3-50, and W51 South suggest that the speed of expansion may vary with evolutionary stage. Other sources exhibit complicated maser kinematics. The motions in W75 N VLA 2 are suggestive of a very fast outflow, while other sources appear to have irregular patterns of motions. Further investigation is required in order to determine whether the velocity fields of these sources are inherently irregular or whether the maser proper motions are complicated by the relative motions of multiple exciting sources within a single star-forming region.

A recent VLBA study of the ground-state OH masers in W3(OH) at the highest spectral resolution of the Socorro correlator found velocity gradients across the line widths of nearly all OH masers in the source. It was also found that the magnitudes of velocity gradients of masers in the 1667 MHz transition are systemically smaller than those from the other three ground-state transitions. This is precisely what has been theoretically predicted. The rotationally excited 6.0 GHz transitions of OH will be observed with the EVN to test whether theoretical predictions of the magnitudes of velocity gradients in other OH-maser transitions are consistent with observations.

While pumping models for many maser species are well understood, theoretical models for OH have had only limited success in reproducing observed conditions, and conflicting models are found in the literature for even the simplest cases. It is incumbent upon maser observers to assist their cause by detecting or constraining fluxes of the intermediary lines required to pump the observed ground-state masers. To this end, rotationally excited transitions of OH will be observed with the VLA toward a sample of supernova remnants and OH/IR stars known to host ground-state masers. A detection of an

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excited-state maser would place tighter constraints on the physical parameters in a single source, and non- detections will contribute significantly to placing rigorous bounds on the ranges of physical parameters allowed in the ensemble of these sources.

The GBT has already proved itself to be the premier astrochemistry instrument in the search for new molecular species in interstellar and circumstellar environments. However, in addition to adding to the list of new molecular species, the GBT along with VLA is beginning to answer questions about the formation of molecules in the ISM. For the first time, high-resolution and high-sensitivity instruments are available to accurately measure and map the locations of molecular species in the ISM with respect to the infrared or millimeter-wave continuum sources primarily heated by thermal processes or shocked regions that are traced primarily by molecular maser emission. Observations of the abundances and locations of molecular species will determine whether the molecular species are formed via gas-phase or grain-surface chemistry as well as how the species were liberated into the gas phase. Over the next year, the GBT will investigate the interstellar chemistry of the low mass star forming region IRAS 16293−2422 by searching for complex molecular species including formic acid (HCOOH), methyl formate (CH3OCHO), methyl cyanide (CH3CN), dimethyl ether (CH3OCH3), and ethyl cyanide (C2H5CN) at Q band. In addition, the GBT will continue the investigation of the best known source for large molecules in the Galaxy, the high- mass star-forming region Sgr B2(N), by searching for interstellar hydrogen peroxide (H2O2). We expect that hydrogen peroxide is spatially extended since most molecules found at Ku to Ka band are not attributed to hot cores but rather are spatially widespread in the gas phase owing to large-scale shocks in the low-density regimes in the vicinity of star-forming regions such as SgrB2(N).

The GBT will be used to characterize known molecular probes commonly used in studies of protostellar evolution. It is generally held that the N2H+ and CCS molecules are unbiased probes of dense pre- protostellar cores. Recently, systematic differentiation of CO, CS, N2H+, and NH3 toward a sample of five starless cores in the Taurus region has been observed. The results of these measurements indicate 5 -3 that the abundances of the CO and CS molecules drop dramatically within the denser [n(H2)>10 cm ] regions of these cores, while the abundances of N2H+ and NH3 remain flat or increase in these regions. OVRO, VLA, and BIMA observations of the N2H+, NH3, and CCS emission toward the cold core containing the low-luminosity IRAM 04191 protostar are not consistent with these conclusions. In the 6 -3 even-denser regions of the cores [n(H2)>10 cm ] high resolution is required to study abundance 6 -3 variations. The observations under study suggest that, for densities exceeding n(H2)>10 cm over regions <15 arcsec in diameter, NH3, N2H+, and CCS become depleted in a similar fashion. This result is important because it suggests that the only molecular probes observable from the ground of the innermost regions may be H2D+ (difficult to observe at 372 GHz) and H3O+ (equally difficult to detect). We need molecular probes if we are to know the kinematics of these inner regions critical to disk/star/outflow interactions. To this end, the GBT will be used to obtain measurements of the CCS emission toward a sample of pre-protostellar and protostellar cores. The intent of this study will be to derive the depletion history of CCS within the early evolutionary sequence of a protostar.

The GBT will be used to survey the H2CO 2(11)–2(12), 3(12)–3(13), and 4(13)–4(14) emission toward a sample of star-formation regions to exactly identify the high-density locations within star-formation regions, which will give us a gas-density measurement that can be used to compare with the physical properties derived from dust emission and infrared measurements of these regions.

The GBT will be used to image protostellar cores at λ = 7 mm and λ = 9 mm. High-spatial-resolution measurements of the centimeter-wavelength dust continuum emission are key to these evolutionary characterizations, as long-wavelength dust continuum emission has the highest probability of being optically thin and therefore a direct measure of the mass in a protostellar core. The GBT is the most sensitive telescope at long millimeter wavelengths. When combined with dust continuum observations at

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submillimeter wavelengths, millimeter continuum observations provide a substantial lever arm to constrain dust opacities.

Molecular outflows from massive young stellar objects (early B and O spectral types) are both well collimated and poorly collimated. In 2005 scientists at the NRAO and the CfA proposed a new evolutionary sequence to explain the observable outflow signatures: outflows should become less collimated when the star turns onto the main sequence because the increased ionization and turbulence would alter the balance between magnetic and plasma pressure in the jet. In 2005 and 2006 the first observations were made with the VLA to test this proposal. Deep multi-configuration observations of ionized gas in λ = 3.6 cm continuum emission were made of eight sources to trace flow morphology, energetics, and ionization structure within 100 AU of the protostar where it is expected that magnetic and/or hydrodynamic collimation takes place. The last A-array data were obtained in May 2006. Preliminary combined images of three sources show that the ionized jet has been detected within 100 AU of the star at a sufficient level that the source can be modeled. In one source, the first evidence of interaction between an ionized jet and the UC HII region boundary was obtained. Data reduction and mosaic imaging using multi-scale clean deconvolution is being done with the AIPS++ package.

Several coordinated projects studying the atmospheres and mass-losing regions of Mira stars using the VLBA and IR interferometers will continue. SiO masers, which can be studied using the VLBA, arise between the outer parts of the molecular envelopes studied by near-IR interferometers (IOTA, CHARA) and the dust-forming regions studied by mid-IR (ISI, VLTI/MIDI) interferometers. These coordinated observations can help in the understanding of the mass-loss mechanisms in these evolved stars that are major contributors to the interstellar medium but currently poorly understood. In addition, water-maser sources around Mira and AGB stars can also be used to measure parallaxes, and the peculiar motions will allow simultaneous study of the gas dynamics in the circumstellar envelopes of these late-type stars.

The VLBA and the VLA will be used to study the SiO masers recently detected around the enigmatic variable star V838 Monocerotis. The VLA is being used to monitor the flux densities and spectra of these masers while the VLBA is being used to monitor their spatial distribution. The SiO masers in V838 Mon may be similar to those in late-type Mira variable stars, which are found just outside the photosphere and inside the dust condensation zone. The VLBA observations may also lead to a measurement of the trigonometric parallax and the distance to this unique source.

The VLA and VLBA will be used to check for extended radio emission from symbiotic stars and related objects. Synchrotron jets have been detected during optical outbursts in several of these sources (cf. the 2006 outburst of RS Oph), showing that white dwarfs as well as neutron stars and black holes can produce extended synchrotron emission. The details of the creation and evolution of such jets remain a mystery; for instance, it is not clear why some outbursts (and sources) create jets while others don't, and in most cases there are only very poor images, with no clear indication whether these are working surfaces (as in the lobes of radio galaxies), highly collimated jets, or random `blobs' of relativistic gas. A larger sample of well-studied objects would help enormously, and the VLA and VLBA will provide detailed imaging sequences for any significant UV/X-ray outbursts.

This year will see the results of a two-year VLA monitoring program of 43 GHz SiO masers in the direction of the Galactic center. Some of these masers are strong and reliable enough (in flux density) to be used as calibrators for Galactic-center VLBI observations.

The Galactic Center, Pulsars, Novae, Supernovae, X-ray Binaries, and other Radio Stars

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In the coming year the VLA will be used to create a multi-configuration λ = 90cm image of 5 square degrees around the Galactic Center (GC). These data will be sensitive to structures ranging in size from 30 arcsec to 50 arcminutes, and they will allow us to study over an unprecedentedly large area the nonthermal features at the GC with high sensitivity and resolution. For example, the enigmatic GC Omega lobe—a 1 degree size feature that may trace a period of previous starburst activity in our GC. We will also be able to determine the full angular extent of nonthermal filamentary features that are thought to trace the orientation of the magnetic field in the high-density environment of the GC region. Recent evidence suggests that the morphology of the GC field may be much more complicated than previously thought; therefore a complete understanding of their radial distribution and orientations with respect to the GC is critical. We also anticipate discovering a number of previously unknown supernova remnants with these high-dynamic-range data.

New λ = 1.1 mm and λ = 350 µm continuum maps of the Galactic Center (Sagittarius A and the Arches filaments) will be published and compared with archival data, including VLA radio and SCUBA (λ = 450 and 850 µm) maps.

The nature of the millimeter- and centimeter-wavelength variability of Sgr A* will be investigated using VLA, ATCA, and CARMA observations. Of particular interest is the issue of short-timescale variability at millimeter wavelengths and its possible connection to IR and X-ray flares. The intraday variability of the 86 GHz emission of Sgr A* is being debated as current observational strategies for phase referencing to an external calibrator source are not reliable at this high frequency. A new technique will be reported on, using 86 GHz SiO masers in the primary beam to reference the possible intraday fluctuations in Sgr A*.

The GBT will be used to carry out a deep targeted 15 GHz search for pulsars lying on <100 year orbits around the Galactic Center. We find that this is the optimal frequency at which to search for both normal and irregular pulsars near the Galactic Center that might be used to test predictions of general relativity in the strong-field regime. We expect to find between 2 and 30 pulsars, assuming a 20% beaming fraction and including uncertainties in the distribution of pulsar spectral indices and the total number of pulsars in this region.

Radio interferometry is an effective tool for determining the kinematics of pulsars. The VLBA in particular has been a productive instrument in the determination of pulsar distances via annual parallax measurement, and hence their velocities as well. The VLBA will be used in the astrometry of more scientifically interesting pulsars over the next year.

VLBI using four large telescopes (Greenbank, Arecibo, Jodrell Bank, and Westerbork) will be applied to studies of pulsar scintillation. Traditionally pulsar scintillation has been restricted to single-dish measurements. However, with deeper understanding of the scintillation mechanism via observations of “scintillation arcs” in the pulsar's secondary power spectrum, VLBI will contribute uniquely to determine astrometrically the nature of the scattering material causing the scintillation.

The excellent pulsar search capabilities of the GBT at 350 MHz will allow us to finish the most sensitive pulsar survey ever of the northern Galactic plane. The survey has already produced at least 14 new pulsars, 3 of which are RRAT-like (Rotating Radio Transients) in nature, and should produce many more new pulsars, including one or more very rare millisecond pulsars (MSPs). The discovery of even a single new “well timing” northern MSP may be essential to the success of pulsar timing arrays for discovering extremely low-frequency gravitational waves. An extension of the survey to the entire northern sky will likely begin this year as well.

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The low-interference and high-bandwidth capabilities of the S-band receiver / Spigot backend combination will allow us to continue timing the bonanza of at least 56 new MSPs found over the past two years (including the most rapidly rotating neutron star known) in several globular clusters located in the Galactic bulge. Since all the science from pulsars comes from timing observations, it will be incredibly interesting to see what this zoo of new exotic systems provides us. Early results have already provided constraints on the equation of state of matter at supra-nuclear density, and additional timing will allow tests of gravitational theories and neutron-star masses.

In addition to the searches and timing observations, the GBT will continue to push the state of the art in non-traditional pulsar observations like scintillation observations and HI absorption measurements, providing us with key probes into the structure and makeup of the interstellar medium.

Data from the GMRT, VLA, and X-ray telescopes will be combined to probe circumstellar interactions of young supernovae. They will be supplemented with modeling of X-ray emission from radiative reverse shocks of supernovae and theoretical understanding of the rare and unusual type II supernovae.

The VLA and VLBA will continue to observe various core-collapse supernovae. The imaging sequence on SN 1993J in M81 will extend to its 14th year, providing a unique record of the expanding shock front for comparison with models and hydrodynamic simulations. Further observations of SN 1986J in NGC 891 will probe the physical character of the unique source near the center of the expanding shell. This source may be the first direct signature of a compact remnant associated with a recent supernova.

The VLA will continue to be used to study new extragalactic supernovae. After the initial optical discovery of a bright and nearby supernova, the new object will be monitored for radio emission, and, once detected, its spectral evolution will be determined over the next couple of years. Such studies of a variety of objects give important information on the mass-loss rates and circumstellar environments of the pre-supernova stars.

Radio data from the VLA and the VLBA will be used in conjunction with X-ray (RXTE, Swift, Chandra, and XMM), optical/infrared (SMARTS and various other ground-based telescopes), and far-infrared (Spitzer) observations to further explore the connection between accretion and outflow in black-hole and neutron-star X-ray binaries. While the X-rays primarily probe the accretion disk and halo, radio observations provide the only direct and unambiguous indication of a relativistic jet. Current observational studies are limited by small-number statistics, insensitivity, and poor sampling. These limitations will be addressed in several ways. First, a VLA monitoring project will continue to provide crucial radio data on the infrequent X-ray transients and supply suitable candidates for imaging and astrometry using the VLBA. Second, simultaneous X-ray and radio observations will be made of a number of neutron-star binaries to learn whether such binaries follow the same correlations as observed in black-hole systems. Third, a few continually active systems will be observed in an unbiased fashion (not triggered by outburst or other activity) to provide a more uniform view of these systems. VLA imaging will track the creation and evolution of extended jets; VLBA astrometric measurements will provide accurate proper motions, placing constraints on `kick' velocities and birth locations as well as (in some cases) parallaxes; VLBA imaging will show both the “quiescent” behavior and the relation between radio ejections and X-ray state. Such observations may also catch sources before and during, as well as some time after, an outburst; this would provide unprecedented constraints both on ejection times and on the difference between the radio (outflow) behavior in similar X-ray states observed before and after large outbursts.

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A joint Chandra–VLA program will observe black-hole transients as they return to quiescence. The study of the radio/X-ray relation as a function of mass accretion rate, covering six or more orders of magnitude in X-ray luminosity, constrains models of accretion flow (e.g. ADAFs) and jet production.

The mm-wave emission of the prototypical microquasar SS433 will be investigated using CARMA and the VLBA. The technique of rotation-measure synthesis will be applied to the VLBA observations to look for large rotation measures in the central regions of this source.

A new campaign will be undertaken to image the X-ray binary LSI +61 303, a compact object of 2 solar masses orbiting a donor of 14 solar masses in an eccentric orbit with a period of 26.5 days. The radio counterpart flares with a similar period. Previous radio observations have led to confusing results in the literature, with reported velocities ranging from under 1000 km s-1 to 60% of the speed of light. We will conduct ten VLBA observations spaced four days apart over 1.5 cycles of orbital phase, giving a sequence of images sensitive both to low and high velocities, and depicting clearly the evolving radio morphology as a function of binary orbital phase. Earlier astrometric work indicated a high proper motion for this source, but our recent data show that it is immobile. We believe the discrepancy is due to the lack of imaging in the original study, with the structural changes misinterpreted as proper motion. Imaging over a full range of known orbital phases would settle this issue. The evolutionary scenario of Mirabel et al. of a runaway binary with kick velocity produced by an asymmetric supernova will need revision.

Finally, a counterpart to LSI +61 303 is known at 100 MeV, with X-rays weaker by a factor of 100. This distinguishes the object from other microquasars, in which keV X-rays dominate. This source had previously been modeled as inverse-Compton emission from relativistic electrons energized by a pulsar instead of the standard disk/jet models. Most recently a report has been made of a modulation of the emission at 100 GeV. We will explore the relationship of the radio flux and morphology to this modulation.

The Solar System and other Planetary Systems

Observations of radio emission from the Sun and the interplanetary medium offer unique diagnostics of the physical processes that occur in these media. Outstanding problems include chromospheric/coronal heating, magnetic energy release, shock formation, and particle acceleration and transport. The VLA offers the best angular resolution available for probing chromospheric heating. Recent observations at 0.7, 1.3, and 2 cm wavelengths, made jointly with Doppler observations in the visible part of the spectrum, probed oscillation power in the middle to upper chromosphere and will be analyzed to constrain ideas related to dynamical theories of chromospheric heating. In concert with space-based radio and X-ray instrumentation (e.g., RHESSI and STEREO), magnetic energy release in flares and its consequences for electron acceleration and propagation will be addressed. In particular, using hard X-ray and microwave observations, quasiperiodic electron acceleration and release will be explored. In the outer corona and heliosphere, low-frequency radio bursts will be exploited to study electron acceleration in shocks.

In anticipation of the capabilities of next-generation instrumentation (e.g. FASR), new data-measurement and inversion techniques are being developed for solar coronal magnetography. Such observations will rely on broadband imaging spectroscopy and will provide entirely new contraints on the vector magnetic field, many of them unique. For example, in solar active regions thermal gyroresonance provides the only means of measuring strong magnetic fields. In the quiet solar corona, radio and IR observations will together impose strong contraints on the magnetic field.

Passive radio observations of solar-system objects allow properties of their atmospheres, surfaces, and magnetic fields to be inferred. Active radio observations (radar) allow additional properties of surfaces

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and magnetic fields to be inferred, and they can also give insights into the spin state of the probed body. Radio wavelengths are unique in their ability to probe into regions inaccessible to shorter wavelengths, e.g., into the deep atmospheres and into the subsurfaces of planets. They are also unique in their ability to observe in conditions which would make shorter-wavelength observations useless (daylight, cloud cover, etc.). They have therefore made, and continue to make, very important contributions to planetary astronomy and planetary science.

Radar observations of Mars provide important constraints on its surface and subsurface properties, including structure (or “texture”). The combination of the Goldstone transmitter and the VLA provides a powerful direct-mapping bistatic radar instrument which has been used successfully during the oppositions of 1988, 1992/93, and 1999 to make radar-reflectivity maps of the planet. The opposition of 2003 was a fantastic opportunity to continue the successful Goldstone/VLA experiments in this respect. Questions regarding the differences between the south and north ice caps, “Stealth” regions, the Hellas basin, and other interesting areas on the planet can be addressed with data taken during this opposition. Those data are being reduced and prepared for publication. Preliminary results are that the south polar ice cap is quite reflective, including the seasonal cap. This is the first time that an increase in reflectivity from a seasonal cap has been seen, and it can be used to infer that the seasonal cap is thick (≥1 meter) and jumbled. The 2003 Mars opposition also provided an excellent opportunity to once again observe the tenuous water vapor in its atmosphere with the VLA. Reduction of this data will continue; in final form it will be used to constrain the amount and vertical distribution of water vapor in the atmosphere of Mars as a function of time.

Radio observations of Uranus provide important information on the deep atmosphere, including temperature and abundance (notably of ammonia, the major variable contributor to opacity at longer wavelengths). Observations during the next few years will be especially important, as the planet is nearly at equinox. In 2007 its north pole will emerge into sunlight for the first time in 42 years. Observations of the deep atmosphere are critical for deducing the dynamics of the deep (and shallow) atmosphere. A program of VLA observations of the planet during every A configuration will continue, including comparing new results to the very recent results indicating that high northern latitudes are bright—just like the high southern latitudes—and that mid-latitude banding is apparent at high frequencies (K and Q bands). Additionally, new longer-wavelength observations will be compared to recent ones which indicate that the south pole brightening persists to great depths (≥50 bars). Similar observations of Neptune will be used to compare the relative temperature and wind structures of the two planets, yielding information on the relative current energy balance and interior structure of these two giant planets.

Recent observations of Enceladus from the Cassini spacecraft have revealed its enigmatic nature. The south polar region is particularly intriguing, with so-called “tiger stripes” being 70 K warmer than equatorial regions and producing significant amounts of CO2 and H2O. Observations of Enceladus as it occults the radio source 3C 228 will allow for the detection of OH around the that moon, constraining the large-scale distribution of gas in the system and the production rate of water from the body.

VLBA observations will track the Cassini spacecraft, which is now in the Saturn system. From six proposed VLBA runs over the next two years we expect to determine the position of Saturn with respect to the quasar background to 0.1 milliarcsec accuracy. At present the position of Saturn is not known any better than 1.0 milliarcsec.

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Astrometry

The radio source 3C 279 will be observed by the VLBA and other VLBI observatories as its line of sight passes closest to the Sun. The VLBA observations will directly measure the deflection of its radio emission by the solar gravitational field. The observers expect to accurately measure the position of 3C 279 with respect to a series of reference quasars by using the radio phase-referencing technique. These observations will be conducted using the VLBA and VLA at U, K, and Q bands. These observations will allow a determination of the relativistic gamma term to a factor of 10 to 100 times better than previously measured using VLBI. While the Cassini spacecraft passed behind the Sun on its journey to Saturn, additional delay was measured in the spacecraft's downlink signal. The NASA-JPL group measured the solar gravitational gamma to nearly one part in 100,000. We believe that our VLBA observations will be able to independently achieve a result of the same accuracy.

A pilot program using the VLBA will see if phase referencing over wide angles (40 deg) can be successfully done at 2.7 and 5 GHz. If so, then the relative positions of about 20 sources within this large region of sky can be determined to 0.05 milliarcsec accuracy. Ultimately we will build up a catalog of quasar positions around the sky with similar accuracy, which is better than the present ICRF accuracy.

Further VLBA observations are being made to find calibrators near the Galactic plane at 22 GHz. These are needed to provide calibrators for stellar objects which are often close to the plane.

VLBA astrometry of X-ray binaries will measure their space velocities and galactocentric orbits based on VLBA proper motions and optical radial velocities. Space velocities relate to questions such as: Do black holes receive a substantial birth kick as do young pulsars? Does the binary belong to the disk, the bulge, or the halo population? Are black-hole binaries born in the galactic plane, or are they born in globular clusters and ejected after close dynamical encounters, as theorized for millisecond pulsars?

The VLBA will be used in an ongoing project to monitor compact non-thermal radio sources in low-mass star forming regions. The goals of the project are to obtain a highly accurate (<1% error) distance and to measure the proper motion and additional acceleration terms due to the gravitational interaction of these stellar systems. As well as providing the best-ever distances to young stellar objects, this will increase the understanding of the spatial distribution and velocity dispersion in these star-forming regions. The VLBA will also be used to observe one young stellar object that is a spectroscopic binary; in combination with optical spectroscopy, this will allow a very accurate measurement of the masses of the forming stars.

VLBA phase-referencing techniques are being refined to enable locating galactic water masers with a precision of tens of microarcseconds. Proper-motion and parallax measurements of water masers using these techniques will yield geometric distance measurements out to many kiloparsecs, thereby accessing most of the Galaxy. These results have implications for studies of galactic structure and rotation, and of structure and evolution of circumstellar shells and outflows.

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Instrumentation

Algorithms for excising RFI produced by radars and airborne distance-measuring equipment (DME) in the 1.0–1.4 GHz range have proven effective in long-integration astronomical observations using off-line data processing. This technique is being applied to observations intended to confirm or deny the existence of time variability in the redshifted HI absorption line profile of 1127−145 at 1082 MHz, which is in the middle of the DME band. The pulse-blanking algorithms are now being migrated to real-time signal processing FPGA hardware for use at the GBT and the EVLA, and all of this work will be continued in the coming year. A collaboration with BYU is investigating RFI nulling using a focal-plane array feed with encouraging results. RFI monitoring antennas have been installed at the top of the GBT feed arm to provide good-quality reference signals for adaptive nulling techniques to be further developed and applied to TV, cell phone, and other signals that do not lend themselves to pulse-blanking algorithms. Characteristics of RFI signal propagation are being uncovered by these studies and will be applied to signal-strength predictions used in the administration of the National Radio Quiet Zone.

Initial design and development work will begin on a state-of-the-art digital pulsar backend for the GBT. The new machine will be the most advanced pulsar instrument in use anywhere and will greatly increase the already fantastic pulsar capabilities of the GBT. Early design requirements specify that the machine will be capable of baseband recording and coherent de-dispersion of up to ~1 GHz of bandwidth. With high dynamic range, full-Stokes output, and adaptive RFI removal, the new instrument in combination with the GBT will provide some of the highest-precision timing and most-sensitive searches of any pulsar system in the world.

The Penn Array Receiver (PAR), a 64-pixel bolometer array operating in the 86 to 94 GHz range, will be tested on the GBT. The PAR receiver uses Transition Edge Superconducting (TES) bolometers and closed-cycle cryogenics. These technologies are suitable for possible very large bolometer arrays in the future. The PAR will become available as a user instrument at a later date depending on further improvements to the GBT structural stability and surface accuracy. Parallel to this effort, there will be a continued development of high-frequency single-dish imaging techniques. Continuum imaging algorithms for the PAR will be tested and implemented during this period.

The commissioning of the new diffraction-grating spectrometer “Z-spec” at the CSO will be completed. Z-spec uses direct-detection bolometers and achieves a resolving power > 200 over an instantaneous bandwidth from 200 to 300 GHz. It was designed to obtain redshifts for heavily dust-obscured submillimeter galaxies at z > 1 by simultaneous detection of two CO lines. It complements the GBT Zspectrometer by permitting the detection of higher-J CO transitions. In an observing run in April 2005, Z-spec demonstrated its ability to conduct sensitive line surveys of local ULIRGS to search for previously undetected lines in the millimeter window and to accurately measure the relative line strengths and their line-to-continuum ratios.

A wide variety of custom MMIC components will be developed in the coming year. These will be unique components that cannot be found commercially due to their unusually wide bandwidths, cryogenic operation, or non-standard port impedance and configuration. Future MMIC components will include wideband differential low-noise amplifiers for balanced feeds, wideband downconverters, and power amplifiers with improved reliability at higher frequencies than ever before.

Work will also continue in the area of efficient multi-chip integration using commercially available MMIC components wherever possible. These assemblies will be more compact and lightweight than earlier generations of receivers, having advantages in many areas from the cryogenics and power

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distribution, to the antenna mechanical design, and even to the electrical and optical performance of large arrays.

Spacecraft navigation by VLBA astrometry will continue. Enhancements to the correlator delay model were recently completed to permit fringe tracking of moving near-field objects. A series of observations over the next two years will dramatically improve Saturn's ephemeris by tying the position of the Cassini spacecraft directly to the inertial extragalactic reference frame. The planetary ephemeris is an essential tool for studies of solar-system dynamics, interplanetary spacecraft navigation, and tests of general relativity.

The NRAO scientists will continue to support the Long Wavelength Array (LWA) now being developed in the U.S. southwest. In the next year, the optimum configuration for the individual antennas in the LWA will be designed. Development of low-frequency (74 MHz) interferometric calibration and imaging techniques will also be pursued. These techniques are needed for optimizing the scientific results from the current VLA 74 MHz system and for the LWA to achieve its science goals.

Algorithm Development

With the improved sensitivities, wide bandwidths, and ultra-wide fields of new instruments such as the EVLA, ALMA, ATA, LWA, LOFAR, and MWA, image deconvolution errors begin to limit the maximum achievable imaging dynamic range. Making thermal-noise-limited images not only requires imaging the main lobe of the primary beam but also deconvolvng the effects due to sources in the first sidelobe. For dynamic ranges of 104 or greater, errors due to effects previously ignored result in residual errors significantly higher than the thermal noise. These effects include (1) spatially varying gain of the antenna primary beams, (2) time and spatial variations in antenna primary-beam gains due to rotation of the primary beams on the sky as a function of parallactic angle, (3) azimuthally asymmetric polarization response of the antenna, and (4) the use of scale-insensitive deconvolution algorithms.

All of these errors require image-plane corrections. The effects of direction-dependent errors will be even more pronounced for high-dynamic-range mosaic imaging with ALMA. Developing algorithms for applying such corrections efficiently is an important research effort at the NRAO.

Errors due to pixel representation of the sky, particularly of large-scale emission, are the dominant image- plane errors. Three basic algorithms exist that explicitly incorporate information about the scale of emission: Multi-resolution Clean, Multi-scale Clean (MS-Clean), and Adaptive-Scale Pixel Clean (Asp- Clean). Future research will be in three directions: (1) incorporating frequency-dependent modeling of the sky at various scales in conjugation with algorithms that correct for frequency- and polarization- dependent instrumental effects such as primary-beam scaling, beam polarization, and VLA polarization squint, (2) parallelizing various imaging and calibration algorithms, MS-Clean and Asp-Clean in particular, and (3) gaining experience in programming general-purpose FPGA cards for use in offline data-processing algorithms.

Observations with the current VLA and VLBA will be used to study polarization calibration techniques that are expected to be important for the EVLA and ALMA. Work so far has indicated that the instrumental polarization of the VLA, while substantially variable in frequency, is exceptionally stable on timescales of months to years, especially at low frequencies. As EVLA antennas come on-line, their instrumental polarizations are being measured and monitored. Even for total-intensity imaging programs, it is clear that the wider continuum bandwidths of the EVLA will require a fully non-linear and frequency-dependent treatment of instrumental polarization calibration to minimize the associated closure errors and reach the dynamic range for bright sources implied by the advertised EVLA sensitivity. Such

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detailed instrumental polarization calibration has been rarely required at the sensitivities of the current instruments, and a linearized frequency-independent instrumental polarization solution has sufficed for most observations. In fact, the non-linear solution is analytically unavailable to the stand-alone VLA because of the VLA’s small geographical size (and thus lack of differentially varying field-of-view orientation among antennas), so the resulting polarization solution is a relative one, appropriate only for approximate calibration of linear polarization. Combined with the demonstrated instrumental polarization stability, occasional coordinated observations with the VLBA, by virtue of the greater geographical distribution of VLBA antennas, provide a means of establishing an unambiguous absolute instrumental- polarization solution for the VLA/EVLA. The resulting higher dynamic range in total intensity (as well as in linear polarimetry) also implies improved prospects for astronomical circular polarimetry, which has been notoriously difficult at the VLA so far. These studies are the first steps in determining and compensating for the differentially polarized field-of-view of the VLA/EVLA, which will be an important consideration for high dynamic range across wide fields of view. These advances in instrumental- polarization treatment have corresponding importance for ALMA, an instrument which will make polarimetry at millimeter wavelengths routine.

In general, a proper treatment of frequency-dependent calibration issues will be needed to fully realize EVLA capabilities. In addition to instrumental polarization, issues under investigation include (1) coping with calibrators' unknown spectral indices, (2) phase-delay (self-)calibration in lieu of traditional phase calibration (including proper handling of dispersive ionospheric effects), and (3) frequency-dependent primary-beam calibration.

With dynamic scheduling planned for the EVLA and ALMA, new observational strategies for calibration will be necessary to optimize use of telescope time. Ongoing investigations in this area include determining how to fully exploit observations of flux-density/polarization calibrators (e.g., 3C286, which we have traditionally under-utilized) and the stability of our instrument. Each visit to such calibrators should provide a reasonable full-polarization “nominal instrument calibration” database that can be applied to contemporaneous science observations. Such a database could also provide direct feedback to dynamic scheduling (e.g., can certain observations currently be calibrated nominally?) as well as to hardware and software maintenance. Such calibration schemes will require a unified full-polarization calibration framework such as the CASA software package provides.

Work on the algorithm-development software platform “Obit” will continue. This package has advanced to the point that it is being used to develop techniques for dealing with VLA instrumental defects and widefield imaging problems.

Powerful data-analysis techniques with which to analyze interferometric polarimetric observations of the CMB and the SZE continue to be developed and are being distributed to the community.

The GBT digital spectrometer offers the potential of sensitive broadband continuum polarimetry using techniques of correlation spectropolarimetry. Several projects are underway to measure CMB foregrounds in this fashion. In order to get the science we need to develop and assess new data-processing strategies.

Array receivers on single-dish radio telescopes in principle offer significant advantages over single- or dual-pixel receivers for imaging beyond a simple increase in mapping speed. With data from the Penn Array Receiver on the GBT to be acquired in the fall of 2006, we will begin to investigate what can be achieved with new single-dish imaging techniques.

Miscellaneous

Program Plan FY 2007 A. Scientific Staff Research Activities 139

Research into the life and scientific research of the Australian radio physicist and early radio astronomer Ruby Payne-Scott will continue in 2007. Payne-Scott worked at the CSIRO Division of Radiophysics from 1941 to 1951 and was the first woman radio astronomer. Her initial radio-astronomical observations consisted of λ = 10 cm observations made during World War II (March 1944) from Sydney. The galactic plane was observed and not detected. The classified report is quite prescient in the realization of many details about radio-astronomy techniques. In 1946 she played a key role in detecting (200 MHz) Type I solar bursts from the giant sunspot regions of early February. These were the first interferometric observations made in radio astronomy. At the end of her career at CSIRO in 1951 she worked with Alec Little in the development of a swept-frequency interferometer at 97 MHz that showed the motions of Type IV bursts far out in the solar corona. Payne-Scott left CSIRO just before her first child was born in late 1951.

The NRAO Archives has acquired materials relating to the founding of the NRAO. These resources will be used to trace the controversies and conflicting goals of the U. S. postwar scientific elite and the development of the NRAO into a user-based astronomical observatory.

Program Plan FY 2007 A. Scientific Staff Research Activities 140

B. Research Staff

Research Staff With Tenure

T. S. Bastian—Solar/stellar radiophysics, flares, coronal mass ejections, solar chromosphere, radio propagation in the interplanetary medium, radio interferometry; Frequency Agile Solar Radio telescope (FASR) planning.

A. H. Bridle—Extragalactic radio sources, Computing and Information Services scientific support, intersite communications support, grad student and visiting scientist support.

C. Carilli—Galaxy formation, radio galaxies, QSO absorption lines, epoch of reionization; Head of North American ALMA Science Center (NAASC).

J. J. Condon—Dark energy, Hubble constant, nearby galaxies, evolution of star formation, radio surveys, GBT precision telescope control system; Special Assistant to the Director.

W. D. Cotton—Extragalactic radio sources, interferometry, cosmic masers, computational techniques for data analysis, scientific support: NRAO sky surveys.

J. R. Fisher—Cosmology, signal processing, antenna design, advanced receiver development; NRAO Technical Leader for R&D.

E. B. Fomalont—Astrometry, X-ray binaries, deep imaging, relativity tests, VSOP and RadioAstron coordination, VLBA support, CASA testing, e2e Operations.

D. A. Frail—Gamma-ray bursts, soft-gamma-ray repeaters, pulsar/supernova remnant associations, pulsar wind nebulae, masers, HI absorption and interstellar scattering; Head of Division of Science and Academic Affairs.

W. M. Goss—Galactic-center studies, galactic masers, pulsars, supernova remnants, nearby galaxies.

K. I. Kellermann—Radio galaxies, quasars, cosmology, SKA design, radio telescopes; Head of New Initiatives Office.

A. R. Kerr—Millimeter-wave receiver development, SIS mixer design, ALMA Project.

H. S. Liszt—Molecular lines, mm-wave absorption-line spectroscopy, diffuse clouds, the galactic center and galactic structure; manager of the NRAO's foreign telescope travel support program, director of the NRAO's spectrum-management activities.

K. Y. Lo—Galactic center, star formation in dwarf galaxies, starburst galaxies and high-redshift galaxies, megamasers and AGN, intergalactic medium, microwave background radiation, millimeter- and submillimeter-wave interferometry; Director.

F. J. Lockman—Galactic structure, interstellar medium, and H II regions, GB education and outreach, student programs; GBT Principal Scientist.

Program Plan FY 2007 B. Research Staff 141

S. Myers—Cosmology, cosmic background radiation, gravitational lenses, astronomical imaging, ALMA and VLA/EVLA scientific support, algorithm development; CASA Project Scientist.

P. J. Napier—Antenna and instrumentation systems for radio astronomy.

F. N. Owen—Evolution of galaxies, clusters of galaxies, radio galaxies, deep continuum surveys; EVLA.

R. A. Perley—Radio galaxies, QSOs, interferometer techniques; EVLA Project Scientist.

M. Pospieszalski—Microwave and millimeter-wave low-noise devices, circuits and receivers, CMBR radiometers, EVLA/VLBA/GBT/ALMA receiver development support.

D. S. Shepherd—Star formation, molecular outflows, disks around luminous young stellar objects, molecular chemistry, millimeter interferometry and mosaic techniques; Deputy Division Head, ALMA Computing.

B. E. Turner—Galactic and extragalactic interstellar molecules, interstellar chemistry, galactic structure.

J. S. Ulvestad—Seyfert, LINER, and starburst galaxies; extragalactic gamma-ray sources; Assistant Director, New Mexico Operations.

J. M. Uson—Cosmology, dark matter, clusters of galaxies, superthin galaxies, spectral synthesis imaging; EPO scientist.

P. A. Vanden Bout—Interstellar medium, star formation, high-redshift molecular emission galaxies, galaxy formation/evolution.

H. A. Wootten—Star formation, structure and chemistry of the ISM in galaxies, circumstellar material; ALMA Project Scientist.

Tenure-Track Astronomers

C. Brogan—High-mass star formation, astrochemistry, masers, magnetic fields, supernova remnants, small-scale structure in the interstellar medium; ALMA/NAASC.

B. S. Mason—Cosmology, cosmic microwave background, high-frequency instrumentation development for the GBT.

S. M. Ransom—Pulsar searches and timing (especially binary and millisecond pulsars); GBT pulsar infrastructure improvement.

Scientist/Astronomy

D. S. Balser—Galactic structure and abundances, H II regions, planetary nebulae; GBT scientific support.

R. C. Bignell—High-redshift absorption systems, planetary nebulae, polarization; GBT scheduling.

Program Plan FY 2007 B. Research Staff 142

J. Braatz—Cosmic masers, active galaxies, cosmology, molecular gas in AGNs, scientific software and algorithms; GBT science support.

B. J. Butler—Planetary astronomy; EVLA System Engineer for Software.

C. Chandler—Star formation, circumstellar disks, protostellar outflows, millimeter-wave interferometry; Division Head, Socorro Scientific Services.

M.J. Claussen—Masers, young stellar objects, AGB stars, pre-planetary nebulae, spectropolarimetry, VLA/VLBA user programs, VLA+Pt link support, VLA and VLBA scientific support, EVLA testing.

V. Dhawan—Radio and X-ray observations of microquasars, VLBA astrometry, VLBA user support and EVLA testing.

D. T. Emerson—Nearby galaxies, millimeter-wave techniques and instrumentation, spectrum management; chairman of the NA ALMA Technical Advisory Committee and of the Observatory Technical Council.

F. D. Ghigo—X ray binaries, AGNs, interacting galaxies; GBT scientific support (VLBI).

E. J. Hardy—Cosmology, galaxies, stellar populations; NRAO/AUI representative in Chile.

J. E. Hibbard—Extragalactic HI, galaxy evolution, merging galaxies, spectral synthesis imaging; NA ARC Manager.

P. R. Jewell—Interstellar molecules, molecular spectroscopy; Deputy Director.

G. I. Langston—Gravitational lenses, galactic-plane transient surveys, searches for extra-solar planets; GBT scientific support.

R. J. Maddalena—Molecular clouds, galactic structure, interstellar medium; Head, GBT Science Operations.

J. G. Mangum—Star formation, astrochemistry, molecular spectroscopy of comets; ALMA.

M. M. McKinnon—Pulsar astrophysics, radio polarimetry, statistics; EVLA Project Manager.

A. H. Minter—Interstellar turbulence and galactic HI, GBT scientific support.

K. O'Neil—Extragalactic gas and dust, low-surface-brightness galaxies; Head, GBT Program Development.

R. Prestage—Telescope performance and control, telescope metrology; Assistant Director, Green Bank Operations.

J. D. Romney—Active extragalactic radio sources, interstellar medium, VLBI instrumentation, VLBA scientific support, spectrum management; VLBA Spacecraft Navigation Pilot Project Manager.

Program Plan FY 2007 B. Research Staff 143

M. P. Rupen—X ray binaries and transient sources, supernovae, interstellar medium; VLA and EVLA scientific support.

L. O. Sjouwerman—Circumstellar masers and AGB stars, centers of the galaxy and Andromeda, VLA/VLBA data-reduction pipelines in AIPS, VLBA/HSA data calibration and archiving, VLA/VLBA scientific support.

R. A. Sramek—Normal galaxies, quasars, supernovae, aperture-synthesis techniques; Deputy Assistant Director, ALMA.

R. C. Walker—Extragalactic radio sources, VLBI, VLBA development, VLBA scientific support, EVLA and SKA design.

J. M. Wrobel—Low-luminosity active galactic nuclei, VLA/VLBA scheduling, PST subsystem scientist.

Scientist/Research Engineering

R. Bradley—Millimeter electronics, low-noise amplifiers, array receivers, adaptive RFI excision, advanced receiver development.

W. Brisken—Pulsars, astrometry, disk-based VLBI.

E. W. Bryerton—Millimeter-wave receiver development and HEB mixer research, ALMA local-oscillator development.

J. Cheng—Structural design and analysis, astronomical telescope design, sensors, carbon-fiber material, ALMA antenna development.

M. Morgan—Millimeter-wave MMIC design, MMIC-based instrumentation, arrays, receiver component development for EVLA, GBT, ALMA, and SKA.

S. K. Pan—Superconducting millimeter- and submillimeter-wave low-noise devices, circuit and receiver development; CDL.

J. M. Payne—Telescope optics, millimeter-wave receivers, metrology systems, cryogenic systems, local- oscillator development; ALMA.

K. Saini—ALMA local-oscillator development, frequency-multiplier development, ALMA Front-End System engineering.

S. Srikanth—Development of polarizers for mm wave applications and broadband prime-focus feeds at cm wavelengths.

J. C. Webber—Instrumentation development, program planning; Assistant Director for CDL; ALMA IPT Leader for Front End and Correlator.

Program Plan FY 2007 B. Research Staff 144

Scientist/Computational Science

J. M. Benson—Extragalactic radio sources, VLBA image processing, scientific support for VLA/VLBA correlator, development and maintenance of the NRAO Science Data Archive, member of the e2e-EVLA Computing Group.

S. Bhatnagar—Supernova remnants, HII/UCHII regions, low-frequency mapping of the galactic plane, interferometric calibration, image reconstruction, and related algorithm development; CASA.

K. Golap—Low-frequency calibration and imaging, imaging algorithm development; CASA.

E. W. Greisen—Radio galaxies, HI in galaxies, interstellar medium, computer analysis of astronomical data, AIPS.

M. A. Holdaway—Imaging methods, mosaicing, calibration, tropospheric transmission, site testing, simulations, operational optimization, configuration design; ALMA.

L. Kogan—Maser radio sources, theory of interferometry, design of array configurations; AIPS group.

J. P. McMullin—Star formation, interstellar medium, astronomical software systems; ALMA CIPT offline-subsystem lead, Science Software Group Project Manager.

A. J. Mioduszewski—Microquasars, symbiotic stars, astrometry of young stellar objects; AIPS, VLBA, and VLA support.

G. Moellenbrock—Polarization interferometry, VLBI techniques, blazars, calibration and imaging algorithms, software for ALMA and EVLA, VLA and VLBA user support.

G. A. van Moorsel—Dynamics of galaxies and groups of galaxies, techniques for image analysis.

Scientist/Emeritus

B. G. Clark—EVLA control and software development, VLA/VLBA scheduling; Emeritus Scientist.

M. A. Gordon—CO, galactic structure, gas-rich galaxies, interstellar medium; Emeritus Scientist.

D. E. Hogg—Structure of spiral galaxies, stellar winds; general support for the Director’s Office, Emeritus Scientist.

M. S. Roberts—Extragalactic hydrogen, normal galaxies, dark matter; Emeritus Scientist.

A. R. Thompson—Emeritus Scientist.

Program Plan FY 2007 B. Research Staff 145

Jansky Fellows

J. Aguirre—Millimeter-wave instrumentation and data analysis, particularly for bolometer detectors; continuum and CO detection of submillimeter galaxies at high redshift; massive-star formation in the Galaxy; Jansky Fellow.

P. Chandra—Circumstellar interactions of supernovae and gamma ray bursts; Jansky Fellow.

T. Cheung—Multi-frequency studies of jets in AGN, VLBI polarimetry; Jansky Fellow.

V. Fish—Masers, magnetic fields, high-mass star formation, molecule searches; Jansky Fellow.

M. Haverkorn—Galactic magnetism, structure in the interstellar medium, radiopolarimetry; Jansky Fellow.

N. Kanekar—Galaxy formation, damped-Lyα systems, OH megamasers, structure of the ISM, the evolution of fundamental constants; Jansky Fellow.

J-P. Macquart—Interstellar scintillation, structure of the ISM, intra-day variability, AGN polarization and structure, gravitational radiation; Jansky Fellow.

D. Meier—Physical and chemical properties of nearby galaxies, young starbursts/super star cluster formation, interstellar prebiotic chemistry; Jansky Fellow.

N. Miller—Clusters of galaxies, multiwavelength studies of galaxy evolution; Jansky Fellow.

K. Spekkens—Spiral, galaxy structure and dynamics, dark matter, galaxy scaling relations, HI morphology of galaxies, disk-halo connection; Jansky Fellow.

NRAO Postdoctoral Fellows

L. Morgan—Galactic triggered star formation, high-frequency instrumentation development for the GBT, GBT scientific support; NRAO Postdoc.

A. Remijan—Astrochemistry, astrobiology, physical and chemical conditions of the interstellar, circumstellar, and cometary media; NRAO Postdoc.

D. Whysong—AGN, unification models, detection of the ionized IGM, dynamics; NRAO Postdoc.

Program Plan FY 2007 B. Research Staff 146

C. Management Staff

Executive Management Group Lo, K.Y. Director Jewell, Philip Deputy Director Clark, George Associate Director for Administration Russell, Adrian NA ALMA Project Director, NA ALMA Project Manager Ulvestad, Jim Assistant Director for New Mexico Operations Prestage, Richard Assistant Director for Green Bank Operations Radziwill, Nicole Assistant Director for End to End Operations Webber, John Assistant Director, Central Development Laboratory Frail, Dale Head of Division of Science and Academic Affairs Adams, Mark Head of Education and Public Outreach Division Kellermann, Ken Head of New Initiatives Office Hubbard, David Head of Program Management Office Condon, James Special Assistant to the Director

Administration Clark, George Associate Director for Administration Williams, Connie Fiscal Officer Bolyard, Jody Safety & Environmental Protection Manager, NA Executive Safety Representative D’Angio, Robert Human Resources Manager Norville, Roy Deputy Human Resources Manager Miller, Ted Observatory Business Manager Welty, Don Senior Budget Manager Plumley, Christine Budget Manager

ALMA Russell, Adrian NA ALMA Project Director, NA ALMA Project Manager Carilli, Christopher Head of NA ALMA Science Center Hibbard, John Acting Head, North American ALMA Regional Center Porter, William NA ALMA Business Manager, NA ALMA Deputy Project Manager Hardy, Eduardo NRAO/AUI Representative in Chile Pilleux, Mauricio Chile Business Manager Davies, Antony NA ALMA Project Controller Wootten, Al NA ALMA Science IPT Leader Glendenning, Brian NA ALMA Computing Division Head/IPT Leader Janes, Clinton NA ALMA Backend Division Head/IPT Leader Perfetto, Antonio NA ALMA Project Deputy Division Head Shepherd, Debra NA ALMA Computing Deputy Division Head Sramek, Richard NA ALMA SSI IPT Leader Webber, John ALMA Correlator and Front End IPT Leader Zivick, Jeff NA ALMA Antenna IPT Leader

Program Plan FY 2007 C. Management Staff 147

Central Development Laboratory Webber, John Assistant Director, Central Development Laboratory, ALMA Correlator and Front End IPT Leader Pan, ShinKuo Deputy Assistant Director, Central Development Laboratory

Computing and Information Systems Hunt, Gareth Head of Computing and Information Systems e2e Operations Radziwill, Nicole Assistant Director for End to End Operations Fomalont, Edward Principal Scientist and Deputy Assistant Director for End to End Operations

Green Bank Operations Prestage, Richard Assistant Director for Green Bank Operations Lockman, Felix Principal Scientist for the Green Bank Telescope (GBT) Holstine, Michael Green Bank Business Manager Maddalena, Ronald Head of GBT Science Operations O’Neil, Karen Head of GBT Program Development Anderson Jr., Robert GBT Telescope Operations Division Head Clark, Christopher Green Bank Computing Division Head Egan, Dennis Green Bank Mechanical Engineering Division Head Norrod, Roger Green Bank Electronics Division Head Shelton, Amy Green Bank Software Development Division Head

Program Management Office Hubbard, David Head of Program Management Office Beverage, Charles Management Information Systems Manager

New Mexico Operations and EVLA Project Ulvestad, James Assistant Director for New Mexico Operations McKinnon, Mark EVLA Project Manager Lagoyda, Skip Socorro Business Manager Chandler, Claire Socorro Scientific Services Division Head Perley, Margaret Socorro Array Operations Division Head Durand, Steven Socorro Electronic Division Head Serna, Lewis Socorro Engineering Services Division Head Butler, Bryan EVLA Computing Division Head Robnett, James Socorro Computing Infrastructure Division Head Thunborg, Jon Socorro Engineering Services Deputy Division Head McMullin, Joe Science Software Group Project Manager Golap, Kumar Science Software Group Deputy Project Manager

Program Plan FY 2007 C. Management Staff 148

D. Committees

External Committees

The NRAO Visiting Committee

The NRAO Visiting Committee is appointed by the AUI Board of Trustees to review the management and research programs of the Observatory. The Visiting Committee met in Green Bank in 2006, Charlottesville in 2005, and Socorro in 2004 and 2003. The current membership and terms are listed below.

Stefi Alison Baum, Rochester Institute of Technology ...... 2005–2008 Roger J. V. Brissenden, Smithsonian Astrophysical Observatory, 06 Chair...... 2003–2006 John E. Carlstrom, University of Chicago ...... 2003–2006 Rodger Doxsey, Space Telescope Science Institute ...... 2004–2007 Reinhard Genzel, Max Planck Institute for Extraterrestrial Physics...... 2005–2008 Victoria M. Kaspi, McGill University ...... 2006–2009 Douglas Lin, University of California, Santa Cruz...... 2005–2008 George K. Miley, Leiden Observatory...... 2003–2006 David B. Sanders, IfA, University of Hawaii ...... 2006–2009 Jonas Zmuidzinas, California Institute of Technology ...... 2005–2008

The Users Committee

The Users Committee is made up of users and potential users of NRAO facilities from throughout the scientific community. It advises the Director and the Observatory staff on all aspects of Observatory activities that affect the users of the telescopes. This committee, which is appointed by the Director, meets annually in May or June. The current membership and terms are listed below.

Robert Becker, University of California, Davis...... 2004–2008 Geoffrey Bower, University of California, Berkeley...... 2004–2008 Scott Chapman, Caltech...... 2006–2010 Tracy Clarke, Naval Research Laboratory...... 2005–2009 Jeremiah Darling, CASA, University of Colorado ...... 2004–2008 Erica Ellingson, CASA, University of Colorado ...... 2006–2010 Gary Fuller, University of Manchester Institute of Science and Technology...... 2003–2007 Bryan Gaensler, Harvard University...... 2004–2008 Paul Green, Harvard-Smithsonian CfA ...... 2006–2010 Luis Ho, Carnegie Observatory ...... 2006–2010 Jan Michael Hollis, NASA-GSFC ...... 2005–2009 Rob Ivison, Royal Observatory, Edinburgh...... 2005–2009 Henry (Chip) Kobulnicky, University of Wyoming ...... 2003–2007 Stanly Kurtz, UNAM Institute de Astronomia ...... 2003–2007 Cornelia Lang, University of Iowa ...... 2004–2008 Mary Putman, University of Michigan ...... 2004–2008 Evan Skillman, University of Minnesota...... 2006–2010 Daniel Stinebring, Oberlin College...... 2005–2009 Michele Thornley, Bucknell University, 2006 Chair...... 2003–2007 Edward Wollack, NASA GSFC...... 2003–2007 Lisa Young, New Mexico Tech ...... 2005–2009

Program Plan FY 2007 D. Committees 149

The Program Advisory Committee

The Program Advisory Committee reviews and provides advice on the long range plan of the Observatory, on new programs and projects being considered for implementation, and on the priorities among Observatory program elements. The current membership and term are listed below.

Neal Evans, University of Texas...... 2006–2009 Shrinivas Kulkarni, Caltech ...... 2006–2009 Elizabeth Lada, University of Florida...... 2006–2009 Lawrence Rudnick, University of Minnesota ...... 2001–2006 Jean Turner, University of California, Los Angeles ...... 2005–2008 Stuart Vogel, University of Maryland...... 2006–2009 Eric Wilcots, University of Wisconsin ...... 2001–2006 Min Yun, University of Massachusetts...... 2005–2008

EVLA Advisory Committee

The EVLA Advisory Committee is to evaluate the EVLA Phase I project progress and requirements and advise the NRAO Director.

Anthony Beasley, ALMA Joint ALMA Office, 06 Chair...... 2004–2006 Marco de Vos, Netherlands Foundation for Research in Astronomy ...... 2001–2006 Sean Dougherty, NRC Herzberg Inst of Astrophysics...... 2004–2006 John Dreher, SETI Project Phoenix ...... 2001–2006 Glen Miller, STScI...... 2006–2008 Gianni Raffi, European Southern Observatory ...... 2004–2006 Mark Reid, Harvard-Smithsonian Center for Astrophysics...... 2001–2006 Luis Rodriguez, Institute de Astronomia UNAM...... 2001–2006 Alan Rogers, Haystack Observatory...... 2001–2006 Stephen Scott,California Institute of Technology, OVRO...... 2001–2006 Tom Soifer, California Institute of Technology...... 2004–2006 Steve Thorsett, University of California, Santa Cruz ...... 2001–2006 Jacqueline van Gorkom, Columbia University ...... 2001–2006 Sander Weinreb, Jet Propulsion Laboratory ...... 2001–2006

Program Plan FY 2007 D. Committees 150

Internal Committees

Observatory Computing Council

The Observatory Computing Council (OCC) has been reorganized this year. The OCC still serves as an advisory group to the Director, but the NRAO e2e Operations Division is now included as it is best positioned to act on OCC recommendations. As noted in the Committee Charter, the OCC is responsible for producing a variety of Briefs and Position Papers during each quarter.

Current members will serve an initial term of 18 months, from July 2006 to December 2007.

NRAO Members and Primary Project/Division Affiliation

Alan Bridle, Chair Brian Glendenning, ALMA Bryan Butler, EVLA Bob Garwood, GBT Crystal Brogan, NAASC Eric Greisen, AIPS Barry Clark, VLA/VLBA/EVLA Gareth Hunt, CIS Bill Cotton, DSAA Steve Myers, CASA Allen Farris, ALMA Doug Tody, NVO Ed Fomalont, End to End Operations

External Members

Dick Crutcher (Illinois/NCSA) Joe Schwarz (ALMA/ESO) Steve Scott (Caltech) Peter Teuben (Maryland) Mel Wright (Berkeley)

Observatory Science Council

The Observatory Science Council (OSC) advises the Director on policy issues related to science and academic affairs at the NRAO. Specific issues include the policies and activities of the DSAA (Division of Science and Academic Affairs.)

Other issues include (1) the review of ideas for new telescopes, or new projects, and new instrumentation for existing telescopes; (2) to stimulate the scientific environment for research throughout the NRAO, including the organization of research support for the scientific staff.

The members of this council are asked to serve initially for a one-year term. Current membership includes:

Fred Lo Dave Hogg Claire Chandler Ken Kellermann Jim Condon Jay Lockman Dale Frail, Chair Frazer Owen Miller Goss

Program Plan FY 2007 D. Committees 151

Observatory Technical Council

The Observatory Technical Council (OTC) will advise the NRAO Director on technical issues that confront the Observatory, and will provide Observatory-wide perspective and coordination in all technical areas, including future planning and R&D, current operations and problems, and projects such as the EVLA and ALMA. To oversee and coordinate technical issues across the Observatory, Rick Fisher has been appointed Observatory Technical Leader, reporting to the Director.

The members of this council serve 3-year renewable terms.

R. Bradley P. Napier W. Brisken R. Norrod W. Cotton J. Payne D. Emerson (Chair) M. Pospieszalski R. Fisher R. Sramek A. Kerr A. Symmes R. Lacasse A. R. Thompson M. Morgan J. Webber

ALMA North American Technical Advisory Committee

In September 2002, this small advisory group was created, to perform an in-depth and end-to-end look at the technical progress of the ALMA construction, on the North American (NA) side. The committee reports to the NRAO Director, who conveys findings back to the JAO and others, as appropriate.

Current membership includes:

D. Emerson, Chair B. Clark P. Napier J. Payne R. Sramek A. Symmes A. R. Thompson

Program Plan FY 2007 D. Committees 152

E. Acronyms and Abbreviations

Acronym Definition 2MASS 2 Micron All-Sky Survey AAS American Astronomical Society ACA ALMA Compact Array ACS ALMA Common Software ACU Antenna Control Unit ADAF Advection-Dominated Accretion Flow AGB Asymptotic Giant Branch AGN Active Galactic Nucleus, or Active Galactic Nuclei AIPS Astronomical Image Processing System AIPT Antenna Integrated Product Team AIT American Institute in Taiwan AIV Assembly, Integration, and Verification ALMA Atacama Large Millimeter Array ALMA-B ALMA Bilateral ALMA-J ALMA Japan ANASAC ALMA North American Science Advisory Committee AOC Array Operations Center (Socorro, NM) AOP ALMA Operations Plan AOS Array Operations Site (ALMA, Chile) APEX Atacama Pathfinder EXperiment APP ALMA Project Plan ARC ALMA Regional Center ASAC ALMA Science Advisory Committee AST Astronomical Sciences (Division of the NSF) ASTE Atacama Submillimeter Telescope Experiment ASTRID ASTRonomer's Integrated Desktop (GBT observing software) ATA Allen Telescope Array ATCA Australia Telescope Compact Array ATF Antenna Test Facility, ALMA Test Facility ATI Advanced Technologies and Instrumentation ATM ATMospheric Sciences (NSF Division) AU Astronomical Unit AUI Associated Universities, Incorporated AZ Azimuth BAE British Aerospace Engineering Systems Company BAL Broad Absorption Line BBC BaseBand Converter BE Back End BEIPT Back-End IPT BIMA Berkeley-Illinois-Maryland Array BU Boston University BUS Back-Up Structure BW Bandwidth BYU Brigham Young University

Program Plan FY 2007 E. Acronyms and Abbreviations 153

Acronym Definition C band 4–8 GHz CARMA Combined Array for Research in Millimeter-wave Astronomy CASA Common Astronomy Software Applications CBI Cosmic Background Imager CCB Caltech Continuum Backend, Change Control Board CCE Common Computing Environment CDL Central Development Laboratory CDR Critical Design Review CfA Center for Astrophysics CFHT Canada-France-Hawaii Telescope CFRP Carbon Fiber Reinforced Plastic CGSR Caltech-Green Bank-Swinburne Recorder CHARA Center for High Angular Resolution Astronomy CII Carbon ion CIPT Computing Integrated Product Team (ALMA) CIS Computing and Information Services cm centimeter CMB Cosmic Microwave Background CO Carbon Monoxide molecule CONACyT Consejo Nacional de Ciencia y Tecnología (Mexico) CONICYT Comisión Nacional de Investigación Científica y Tecnológica de Chile CORF Committee on Radio Frequencies COSMOS Cosmological Evolution Survey (HST Treasury Project) COTS Commercial Off-The-Shelf CRL Carbon Recombination Line CSC Computing Security Committee CSG Core Science Group (in e2e Operations) CSIRO Commonwealth Scientific and Industrial Research Organization (Australia) CSO Caltech Submillimeter Observatory CSV Commissioning and Science Verification (ALMA) CVR Central Variable Reference (ALMA LO system) CWVR Compact Water-Vapor Radiometer CY Calendar Year (January 1 through December 31) DASI Degree-Angular-Scale Interferometer DEIMOS DEep Imaging Multi-Object Spectrograph (Keck) dHEB diffusion-cooled Hot-Electron Bolometer DME Distance-Measuring Equipment DPG Data Products Group (in e2e Operation) DRAO Dominion Radio Astrophysical Observatory DRSP Design Reference Science Plan (ALMA) DSAA Division of Science and Academic Affairs DSP Digital Signal Processing DTS Digital Transmission System e2e End-to-End EoR Epoch of Reionization EPO Education and Public Outreach ERP Enterprise Resource Planning

Program Plan FY 2007 E. Acronyms and Abbreviations 154

Acronym Definition ES&S Environmental Safety and Security ESA European Space Agency ESO European Southern Observatory EVLA Expanded Very Large Array EVLA I Phase I of the EVLA EVLA II Phase II of the EVLA eVLBI Electronic (real-time) VLBI EVN European VLBI Network FASR Frequency-Agile Solar Radiotelescope FCC Federal Communications Commission FCRAO Five College Radio Astronomy Observatory FE Front End FEIC Front- End Integration Center FEIPT Front-End Integrated Product Team FIR Far Infra-Red FIRST Faint Images of the Radio Sky at Twenty cm FPGA Field-programmable Gate Array FRI Fanaroff-Riley type I (edge-darkened) radio morhpology FRM Focus-Rotation Mount FTE Full-Time Equivalent FY Fiscal Year (October 1 through September 30) GaAs Gallium Arsenide GAIA Global Astrometric Interferometer for Astrophysics GASP Green Bank Astronomical Signal Processor GB Green Bank, WV Gbps Giga-bits per second GBT Green Bank Telescope GBTIDL GBT IDL data-reduction package GC Galactic Center GHz Gigahertz GLAST Gamma-ray Largge-Area Space Telescope GLIMPSE Galactic Legacy Infrared Midplane Survey Extraordinaire (Spitzer) GMRT Giant Metrewave Radio Telescope GRB Gamma-Ray Burst GSA General Services Administration HAC Hydrogenated Amorphous Carbon HBT Heterojunction Bipolar Transistor HEB Hot-Electron Bolometer HFET Heterojunction Field-Effect Transistor HI Neutral Hydrogen HIRES High-Resolution Echelle Spectrometer HN Hancock, NH VLBA station HR Human Resources HSA High-Sensitivity Array (VLBA) HST Hubble Space Telescope HVAC Heating, Ventilation, and Air Conditioning IAU International Astronomical Union

Program Plan FY 2007 E. Acronyms and Abbreviations 155

Acronym Definition ICM Intra-Cluster Medium ICRF International Celestial Reference Frame IDL Interactive Data Language IDV Intra-Day Variability I/E Import/Export IF Intermediate Frequency IFP IF Processor (ALMA) IGM Inter-Galactic Medium InP Indium Phosphide IOTA Infrared-Optical Telescope Array IPS Integrated Project Schedule (ALMA) IPT Integrated Product Team (ALMA) IRAC Infra-Red Array Camera (Spitzer) IRAM Institut de Radioastronomie Millemétric IRDC InfraRed Dark Cloud IRS InfraRed Spectrometer (Spitzer) ISD Interferometry Software Division ISI Infrared Spatial Interferometer (Mt. Wilson) ISM InterStellar Medium ISPO International SKA Project Office ITU International Telecommunications Union IUCAF Inter-Union Commission on Frequency Allocation (IAU) IVN International VLBI Network IVOA International Virtual Observatory Alliance JAO Joint ALMA Office JCMT James Clerk Maxwell Telescope JPL Jet Propulsion Laboratory Jy Jansky K band 18–26 GHz band Ka band 26–40 GHz band kHz kiloHertz Ku band 12–18 GHz L band 1–2 GHz LIGO Laser Interferometer Gravitational-wave Observatory LISA Laser Interferometer Space Antenna LLAGN Low-Luminosity Active Galactic Nuclei LNA Low Noise Amplifier LO Local Oscillator LORR Local-Oscillator Reference Receiver (ALMA) LTE Local Thermodynamic Equilibrium LWA Long-Wavelength Array LWDA Long-Wavelength Development Array M&C Monitor and Control M&IE Meals and Incidental Expenses M&S Materials and Supplies MAMBO Max-Planck Millimeter Bolometer MERLIN Multi-Element Radio-Linked Interferometer Network

Program Plan FY 2007 E. Acronyms and Abbreviations 156

Acronym Definition Mbps Mega-bits per second MHz Megahertz MIPS Multi-band Imaging Photometer for Spitzer MIS Management Information Services MK Mauna Kea, HI VLBA station mm millimeter MMIC Monolithic Millimeter-wave Integrated Circuit MoU Memorandum of Understanding MPIfR Max Planck Institut für Radioastronomie MR&D Maintenance, Repair, and Development MRI Major Research Instrumentation MSP MilliSecond Pulsar MSX Midcourse Space eXperiment MUX Multiplexer MWA Mileura Widefield Array NA North American / Not Applicable / Not Available NAASC North American ALMA Science Center NAPO North American Project Office (ALMA) NAOJ National Astronomical Observatory of Japan NASA National Aeronautics and Space Administration Nb Niobium NINS National Institute of Natural Sciences (Japan) NMIMT New Mexico Institute of Mining and Technology NPR National Public Radio NRAO National Radio Astronomy Observatory NRC National Research Council NRL Naval Research Laboratory NRQZ National Radio Quiet Zone NSB National Science Board NSBE National Society of Black Engineers NSBP National Society of Black Physicists NSF National Science Foundation NTC NRAO Technology Center (Charlottesville, VA) NVO National Virtual Observatory NVSS NRAO VLA Sky Survey O&M Operations and Maintenance OH Hydroxyl radical OMT OrthoMode Transducer OPS Operations OPT Optical Pointing Telescope (ALMA) OSF Operations Support Facility (ALMA, Chile) OTC Observatory Technical Council OVRO Owens Valley Radio Observatory P band 327 MHz P2P Procure to Pay PA Power Amplifier PAHs Poly-Aromatic Hydrocarbons

Program Plan FY 2007 E. Acronyms and Abbreviations 157

Acronym Definition PAPER Precision Aray to Probe the Epoch of Reionization PAR Penn Array Receiver (GBT) PBPM Performance-Based Project Management pc parsec PdBI Plateau de Bure Interferometer PDR Preliminary Design Review pHEB phonon-cooled Hot-Electron Bolometer pHEMT pseudomorphic High-Electron-Mobility Transistor PI Principal Investigator PMCS Project Management Control System PMO Program Management Office PMP Program Management Plan PRL Presidential Request Level PSI Prototype System Integration PST Proposal Submission Tool PT Pie Town, NM VLBA station PTCS Precision Telescope Control System Q band 40–50 GHz QSO Quasi-Stellar Object R&D Research and Development REU Research Experiences for Undergraduates RF Radio Frequency RFI Radio-Frequency Interference RHESSI Reuven Ramati High-Energy Solar Spectroscopic Imager RRAT Rotating Radio Transient RXTE Rossi X-ray Timing Explorer S band 2–4 GHz SAO Smithsonian Astrophysical Observatory SC St. Croix, VI VLBA station SCUBA Submillimeter Common-User Bolometer Array SDSS Sloan Digital Sky Survey SE&I Systems Engineering and Integration SETI Search for Extraterrestrial Intelligence SGPS Southern Galactic Plane Survey SHARC Sub-mm High-Angular-Resolution Camera (CSO) SIS Superconductor–Insulator–Superconductor SKA Square Kilometre Array SMT Sub-Millimeter Telescope (University of Arizona) SOI Silicon On Insulator SED Spectral Energy Distribution SMARTS Small and Moderate Aperture Research Telescope System SMC Small Magellanic Cloud SQUID Superconducting Quantum-Interference Device SRBS Solar Radio-Burst Spectrometer (Green Bank) SSS Science Support Systems (EVLA) STEREO Solar–TErrestrial Relations Observatory STG Strategic Technology Group (in e2e Operations)

Program Plan FY 2007 E. Acronyms and Abbreviations 158

Acronym Definition submm submillimeter SWC Southwest Consortium SZE Sunyaev-Zeldovich Effect TB Technical Building TE Timing Event (ALMA LO) TECRO Taipai Economic and Cultural Representative Office TES Transition-Edge Superconducting TFB Tunable Filter Bank THz TeraHertz UCHII Ultra-Compact Ionized Hydrogen (region) UI University of Illinois ULIRG Ultra-Luminous InfraRed Galaxy ULX Ultra-Luminous X-ray source UNAM Universidad Nacional Autonoma de Mexico UNM University of New Mexico UV UltraViolet UVa University of Virginia UVES UV-Visual Echelle Spectrograph UVML University of Virginia Microfabrication Laboratory VCO Voltage-Controlled Oscillator VIMOS VIsible Multi-Object Spectrograph (VLT) VIPS VLBA Imaging and Polarimetry Survey VIVA VLA Imaging of Virgo in Atomic gas VLA Very Large Array VLBA Very Long Baseline Array VLBI Very Long Baseline Interferometry VLSS VLA Low-frequency Sky Survey VLT Very Large Telescope VLTI/MIDI VLT Interferometer/MiD-Infrared Interferometer VO Virtual Observatory VSOP-2 VLBI Space Observatory Program (2nd generation) VSWR Voltage Standing-Wave Ratio W band 68–92 GHz WBS Work Breakdown Structure WHT William Herschel Telescope WIDAR WIdeband Digital INterferometric ARchitecture (EVLA correlator) WMAP Wilkinson Microwave Anisotropy Probe WRC World Radiocommunication Conference WSRT Westerbork Synthesis Radio Telescope WVR Water-Vapor Radiometer X band 8–12 GHz XMM X-ray Multi-Mirror telescope

Program Plan FY 2007 E. Acronyms and Abbreviations 159