NATIONAL OPTICAL ASTRONOMY OBSERVATORIES

NATIONAL OPTICAL ASTRONOMY OBSERVATORIES

Cerro Tololo Inter-American Observatory Kitt Peak National Observatory National Solar Observatory

La Serena, Chile Tucson, Arizona 85726 Sunspot, New Mexico 88349

ANNUAL REPORT

October 1995 - September 1996

October 31,1996

TABLE OF CONTENTS

I. INTRODUCTION

II. AURA BOARD

III. SCIENTIFIC PROGRAM

A. Cerro Tololo Inter-American Observatory (CTIO) 1. The Binary-Star Content of Globular Clusters 2. White Dwarfs and the Age of the Milky-Way Disk 2 3. A Census of the Outer Solar System 3

B. Kitt Peak National Observatory (KPNO) 3 1. Dynamical Processes in Giant H II Regions 3 2. Large-Scale Streaming in the Galactic Halo 4 3. Structure and Dynamics of the Coma Cluster of Galaxies 5

C. National Solar Observatory (NSO) 6 1. First Results from GONG 6 2. Acoustical Events as Source of the Global P-mode Energy 8 3. Chromospheric He I Observations: Looking for Solar Wind and Coronal Rain 8

IV. DIVISION OPERATIONS 9

A. Cerro Tololo Inter-American Observatory 9 1. CTIO Telescope Upgrades and Instrumentation 9 2. Facilities Operations 15

B. Kitt Peak National Observatory 17 1. New KPNO Programs in FY 1996 17 2. KPNO Observing Improvements 18 3. KPNO Instrumentation Improvements 19

C. National Solar Observatory 20 1. Kitt Peak 20 2. Sac Peak 23

D. US Gemini Program 25

E. NOAO Instrumentation Program 27 V. MAJOR PROJECTS 30

A. Global Oscillation Network Group 30 B. Precision Solar Photometric Telescope 32 C. SOLIS 32 D. CLEAR Feasibility Study 33

VI. CENTRAL COMPUTER SERVICES 34

Vn. SCIENTIFIC STAFF 38

A. CTIO Scientific Staff Changes 38 B. KPNO Scientific Staff Changes 38 C. NSO Scientific Staff Changes 39

VIII. DIRECTOR'S OFFICE 39

EX. NOAO STATISTICS 40

A. CTIO Statistics 40 B. KPNO Statistics 41 C. NSO Statistics 42 D. NOAO Tucson Headquarters Building Statistics 42

APPENDICES

Appendix A NOAO Technical Reports List Appendix B CTIO Publications List Appendix C KPNO Publications List Appendix D NSO Publications List I. INTRODUCTION

This report covers the period 1 October 1995 - 30 September 1996.

The National Optical Astronomy Observatories (NOAO) are operated by the Association of Universities for Research in Astronomy, Inc. (AURA), for the National Science Foundation (NSF). The four divisions of the NOAO are: the Cerro Tololo Inter-American Observatory (CTIO) in northern Chile; the Kitt Peak National Observatory (KPNO) near Tucson; the National Solar Observatory (NSO) with facilities on Kitt Peak and at Sacramento Peak, New Mexico; and the US Gemini Program (USGP) based in Tucson. NOAO observing and data reduction facilities are available to the entire astronomical community. The NOAO Home Page contains on-line information about NOAO services, including telescope schedules and instrument availability, and information abouthow to apply for telescope time. The NOAO Home Pagecan be accessed through the World Wide Web at http://www.noao.edu/.

II. AURA BOARD

The NOAO is an operating center managed by AURA, a private, non-profit corporation. There are twenty-eight AURA member institutions, including three international affiliates. The member institutional representatives elect a governing Board of Directors, consisting of thirteen directors (including the President, ex-officio). In addition to NOAO, AURA operates and manages the Space Telescope Science Institute under contract with NASA, and the international Gemini Project under cooperative agreement with the NSF.

III. SCIENTIFIC PROGRAM

The following paragraphs describe only a few of the many ongoing programs of research carried out at the National Optical Astronomy Observatories. The programs described here are representative of the important contributions to scientific research made by NOAO astronomers and NOAO facilities.

A. Cerro Tololo Inter-American Observatory (CTIO)

1. The Binary-Star Content of Globular Clusters

The fraction of binary stars is a basic parameter of any stellar population. The number and types of binary stars are potentially important indicators of the mechanisms by which the stars formed. For dense stellar systems such as globular clusters, the dynamical evolution of the system is intimately tied to the number and type of binary stars present. Perhaps the most dramatic consequence of a population of primordial binaries is their tendency to delay the onset of core collapse.

While initial studies suggested that globular clusters were deficient in the fraction of binaries compared to field stars, a number of more recent results all conclude that the fraction of binaries in globular clusters is roughly comparable to that in the field population. While the current fraction of binaries in globular clusters seems now to be well established, the exact distribution of periods for globular-cluster binaries is still not well known; as we shall see, this could have a bearing on our conclusions concerning the primordial population of binaries.

In two studies, Patrick Cote (DAO) and his collaborators address the question of binaries in globular clusters in very different regimes of orbital period. Using the Argus multi-object spectrograph on the Blanco 4-m telescope, Cote and Philippe Fischer (Michigan U.) have searched for main-sequence binaries with very short periods, between 2 days and 3 years, in the cluster M4. In a sample of 33 main-sequence stars, two show velocity differences of greater than 10 km/s in observations separated by 11 months. Including the efficiency for discovering binaries with different periods and orbital parameters, Cote and Fischer's result yields a binary fraction of 15% in M4.

In a companion study, Cote, Carlton Pryor (Rutgers U.), Robert McClure, J.M. Fletcher and James Hesser (DAO) search for long-period binaries by combining observations of the velocities of red giants in the globular cluster M22 taken over a period of 22 years at Palomar, CFHT, MMT and CTIO. The complete data set, which consists of 333 repeat velocity measurements for 109 stars, does not contain a single star that shows a velocity difference greater than 7 km/s. These observations lead to a binary fraction of < 1% assuming circular orbits; a binary fraction of < 3% results if the assumption of circular orbits is relaxed. A possible explanation for the difference in the binary fraction between the short-period, close binaries in M4 and the long-period, wide binaries in M22 is that loosely bound, wide binaries are more easily disrupted by encounters with other stars than are tightly bound, short-period binaries. Thus, a primordial population of long-period binaries could be destroyed over the life of the cluster.

2. White Dwarfs and the Age of the Milky-Way Disk

White dwarfs are the remnants of low-to-moderate-mass stars after they have completely exhausted their nuclear fuels; our Sun will eventually become a white dwarf in another five billion years. An important result which has come from surveys for faint white dwarfs in the vicinity of the Sun is the absence of low-luminosity, cool white dwarfs. With no internal energy sources, white dwarfs simply cool and grow fainter as they age. Thus the temperatures and luminosities of a white dwarf serve as a cosmic clock, recording the time which has passed since the white dwarf formed. The lack of white dwarfs below a certain critical luminosity indicates that insufficient time has elapsed for these oldest white dwarfs to cool beyond this limiting luminosity. Thus, the ages of the least luminous white dwarfs that can be found provide a lower limit for the age of the disk of the Galaxy.

A necessary step in establishing the age of a white dwarf is to derive quantities such as the temperature, composition and surface gravity of the star from the available observations. Pierre Bergeron (U. of Montreal), Maria Teresa Ruiz (U. de Chile), and S.K. Leggett (U. of Hawaii) have recently completed an extensive study which used the colors and spectra from a large sample of cool white dwarfs to calibrate a state-of-the-art sequence of model atmospheres. The model atmospheres provide the transformation from observed quantities into physical quantities such as the temperature and surface gravity.

Observations were made of 110 white dwarfs, primarily using the telescopes at CTIO. These observations included optical spectroscopy with the CTIO 4-m, infrared photometry with the CTIO 4-m and 1.5-m, and optical photometry with the CTIO 1.5-m and 0.9-m. The principal result of this work is a calibrated and verified set of model atmospheres that describe the observable properties of the coolest white dwarfs.

These model atmospheres can be used to derive the temperatures, masses and luminosities for faint white dwarfs found in present and future surveys. When combined with models for how the temperature and luminosity of white dwarfs change with time as these stars cool, refinements to the model atmospheres should improve the accuracy with which the white dwarf luminosity function may be used to reconstruct the star formation history in the disk of the Galaxy. The oldest white dwarfs in the sample used to calibrate the model atmospheres have ages in the range of 6.5 to 10 billion years. Since this sample is not a complete sample of stars, these ages are strictly a lower limit to the age of the Galactic disk.

3. A Census of the Outer Solar System

Much closer to home, the number and sizes of small, icy bodies in the outer solar system is still poorly known. It is only within the last twenty years that the first of the Centaurs, 100 km-sized objects with orbits between Saturn and Neptune, was found. And it has only been within the past few years that similar objects orbiting beyond Neptune, the Kuiper belt objects, have been discovered. In an effort to improve our knowledge of the contents of the solar system beyond the orbit of Saturn, David Jewitt (U. of Hawaii), Jane Luu (Harvard U.), and Jun Chen (U. of Hawaii) have recently completed the Mauna Kea-Cerro Tololo survey for Centaurs and Kuiper-belt objects. Jewett, Luu, and Chen employed the CTIO 1.5-m telescope to extend coverage into the Southern ecliptic plane for a survey that was begun using the UH 2.2-m telescope on Mauna Kea. The survey revealed 15 new Kuiper Belt objects and 2 Centaurs, bringing the total number of Kuiper Belt objects to 32 and Centaurs to 6. The inferred number of objects in the Kuiper belt at 30 AU to 50 AU heliocentric distance with diameters greater than 100 km is approximately 70,000. The total population of Centaurs with diameters greater than 75 km is about 2600.

B. Kitt Peak National Observatory (KPNO)

1. Dynamical Processes in Giant H II Regions

A giant H II region is a complex of newly formed stars and ionized, neutral and molecular gas, which can contain over a million solar masses of material. The nearest example is the 30 Doradus region in the Large Magellanic Cloud. These are sites of active star formation and deposition of mechanical energy into the host galaxy's interstellar medium. From studies of many such regions, correlations have been found between the luminosity radiated in the H beta line of hydrogen, the physical diameter of the giant HU region, and the integrated velocity width of the emission line. Such correlations suggest unifying underlying physical mechanisms, and several models have been proposed. These models include energy injection from stellar winds, bulk motions induced by supernovae and their remnants, and the overall motions expected of material bound in a gravitational potential.

To explore the physical mechanisms in detail, adequate spatial and velocity resolution are required. Yang (U. of Minnesota), Chu (U. of Illinois), Skillman (U. of Minnesota), and Terlevich (Royal Greenwich Obs.) reported in the July 1996, Astronomical Journal on their study of the giant H II region NGC 604 in the very nearby galaxy M 33. Key components of their database were longslit echelle spectrograms taken with the Mayall 4-m telescope, and narrowband images obtained on the KPNO 2.1-m telescope. The echellograms were taken in a single spectral order to provide an emission-line map ~ 2 arcmin long with velocity resolution of ~ 27 km/s. Nine E-W slices and 2 N-S slices were taken in Ha to produce a 2-dimensional velocity map.

The emission region is very complex, with four expanding shells identified. One is probably asymmetric because of its encounter with an associated molecular cloud; the largest expansion velocity is over 100 km/s. With densities derived from emission line diagnostics and accurate velocity maps, the kinetic energy requirements for driving the shells were derived. They were found to exceed by a factor of at least 3 the energy in stellar winds associated with the hot young stars observed in Hubble Space Telescope images of the region. The extra energy is likely to be attributable to supernova remnants because of the high expansion velocities and the bright, diffuse X-ray emission associated with the shells.

The integrated velocity profile of the H U region has a core with velocity width of 42 km/s and broad wings produced by the fast expanding shells from stellar winds and supernova remnants. Individual emitting sub-regions show line widths of -36 km/s. The gas temperature of 8550 K would produce emission lines of only -20 km/s from thermal motions. Additional broadening is consistent with the motion of gas in the gravitational potential of the 4.7 million solar masses of material in the region. The remaining discrepancy between 36 km/s and 42 km/s is again attributable to the higher velocity regions with stellar winds and supernova remnants, which produce about 1/3 of the total emission line flux.

The conclusion is that the observed velocity profiles in this giant H II region are produced from about equal contributions of internal thermal motion, stellar winds and supernova remnants, and motion in the gravitational potential. Observations in similar detail are required in a number of other regions to verify the global correlations between power, size, and velocity, and to assess the universality of the physical mechanisms at work.

2. Large-Scale Streaming in the Galactic Halo

The spherical halo of the Galaxy was long thought to represent the earliest phase of the Galaxy's formation. Halo stars are very metal-poor, and early samples showed them to have little rotation, in comparison with the rapidly rotating disk. Those facts suggested to Eggen, Lynden-Bell, and Sandage in 1962 that the halo consisted of stars formed during a phase of spherical collapse, with little angular momentum and weak metal enrichment. Newer data collected by S. Majewski (U. of Virginia) and colleagues indicate that the formation history of the halo may be much more complex.

Majewski's original dataset consisted of stars with accurately measured proper motions near the North Galactic Pole. He developed that sample from photographic plates taken at the prime focus of the Mayall 4-m Telescope on Kitt Peak over a baseline of some 15 years. The random error of proper motions of stars as faint as B = 22 mag is 0.1 arcsecond/ century, and the proper motions are tied to the stationary frame of quasars and galaxies in the field to better than 0.01 arcsecond/century accuracy. From that sample, he found that the true halo population does not begin to dominate until distances above the Galactic plane of greater than 5.5 kpc, below which there is an extended or thick disk. A surprising result was that the true halo objects appear to be rotating in retrograde motion of some 55 km/s, instead of being at rest with respect to a disk rotation of 220 km/s. That result contradicts the spherical collapse picture in which angular momentum is conserved in the rapidly rotating disk; a retrograde halo has angular momentum in the opposite direction to that of the disk!

The first conclusions were based on proper (angular) motions only. Radial velocities complete the full 3-dimensional distribution. In the direction of the North Galactic Pole, the radial velocities are directed almost exactly toward or away from the Galactic plane. In the Astrophysical Journal Letters of 10 March 1996, Majewski, J. Munn (U. of Chicago), and S. Hawley (Michigan State U.) report on Hydra multi-fiber spectroscopy of the NGP field. They obtained over 200 new radial velocities for stars with previously measured proper motions with distances out to 8 kiloparsecs from the plane. They found that the stars tend to be concentrated in groups with common space velocities and metallicities. One of the most distinct groups is metal-poor, and is moving toward the Galactic plane with a mean velocity of 56 km/s. That result is consistent with two previous surveys in the same direction, with negative net radial velocities of blue horizontal branch stars, RR Lyrae variables, and A stars. In the initial sample, there are very few stars that are not associated with one of the major common motion groups. The consequence is that the halo is dynamically young, with comingling but identifiable streams of stars of different ages, metallicities and trajectories, presumably from capture of satellite systems by the Milky Way. This "can of worms" model for the halo may explain seemingly discrepant results of surveys of the halo in different directions. Each line of sight may intersect different streams with unique local trajectories dominating the population sample. If that is the case, the entire halo may not be in retrograde rotation, but the halo from 5 to 10 kpc in the direction of the North Galactic Pole is dominated by a stream heading retrograde and down. Ultimately, such studies should allow us to trace the formation history by accretion and tidal shredding of a population of satellites to form the extended, tenuous stellar halo of the Galaxy.

3. Structure and Dynamics of the Coma Cluster of Galaxies

Ongoing observations of the rich Coma Cluster have revealed a cluster in an active dynamical state. It contains at least three giant D and cD galaxies, shows a two-component X-ray morphology, and displays different velocity dispersions for the early and late type galaxies. The signature of the dynamical history of the cluster should be found in the relative motions of the galaxies within it. Although substantial redshift surveys have been undertaken in the past, the Hydra multi-fiber spectrograph has created the opportunity to nearly double the available sample. Finding a significant signal of substructure and mergers is now possible with the new redshift database.

M. Colless (Mt. Stromlo & Siding Spring Obs.), and A. Dunn (Inst, of Astronomy, Cambridge) report in the Astrophysical Journal of 20 February 1996, on their reanalysis of the dynamics of the Coma Cluster based on 243 new redshifts obtained with Hydra plus the bench spectrograph on the KPNO 4-m telescope. Their total sample of cluster members was 552 galaxies. The velocity distribution of the entire sample is inconsistent with that of a single, relaxed population. With a new test for localized departures from a Gaussian velocity distribution, they found a highly significant substructure of galaxies around the cD galaxy NGC 4389, 40 arcminutes SW of the cluster core. That location is essentially identical to the secondary peak of X-ray emission. They applied a mixture-modeling algorithm to assign galaxies to the main cluster and to the NGC 4389 subcluster; the main Coma Cluster is centered on the giant NGC 4874 with a mean recession velocity of 6853 km/s and a dispersion of 1082 km/s. The NGC 4389 cluster has a mean recession velocity of 7339 km/s and a dispersion of 329 km/s.

Using only the galaxies assigned to the main cluster, Colless and Dunn found that the apparent velocity dispersion of the late-type galaxies is V2 x the dispersion of the early- type galaxies, confirming earlier suggestions that the spirals are freely falling into a virialized cluster dominated by early-type systems. They calculated the virial mass for the main cluster to be 0.9 x 1015 solar masses, in excellent agreement with the X-ray results. The smaller cluster around NGC 4389 is bound and contains 5-10% of the mass of the main cluster, again in good agreement with the X-ray observations.

A linear two-body model suggests a most probable orbital configuration for the two clusters. That solution has the NGC 4389 cluster bound to the Coma Cluster, with the two clusters projected at 74° to the line of sight with a true separation of 0.8 Mpc and approaching each other at 1700 km/s. The existence of NGC 4389 as a cD central galaxy, the low velocity dispersion, and distinct X-ray emission all suggest that the NGC 4389 cluster is about to make its first encounter with the Coma Cluster, and has not yet been disrupted by a passage through the main cluster. The NGC 4389 cluster is approaching the main cluster from the direction of the Great Wall.

There appears to be some substructure within the main body of the Coma Cluster itself, consisting of two subclusters: a true central peak close to the projected position of NGC 4874 with mean recession velocity of 6800 km/s, and a secondary peak near NGC 4889 with mean velocity of 7600 km/s. Neither of the giant galaxies lies near the velocity center of its associated spatial sub-condensation. A possible scenario is that the NGC 4889 group is in the process of completing a merger with the larger Coma Cluster group. NGC 4889 itself was ejected from the cluster central potential and lost its cD halo in the process. NGC 4874 was also ejected from the center of the main gravitational potential, and its apparent cD halo could be a projection effect against the stellar population still trapped there.

This study represents another example of the qualitative gains of multi-fiber spectroscopy—in this case, revealing the active dynamical processes at work in the Coma Cluster. Models of mergers and ongoing dynamical relaxation have been previously proposed, but significant results depend on significant quantities of imaging and spectroscopic information.

C. National Solar Observatory (NSO)

1. First Results from GONG

The GONG network became operational in early October 1995. It has lived up to our hopes in terms of operational reliability, observing duty cycle, instrument performance, and data processing capabilities. In addition, the GONG scientific teams—which have been working together since the conception of GONG to define the scientific program and to prepare the analysis techniques—were able to get to work rapidly and effectively. The first fruits of their efforts appeared in a special issue of the journal Science on 31 May. Within the colorful GONG cover, this issue contains seven articles, resulting from the contributions of 71 different authors and a supporting cast of hundreds. These first results just scratch the surface, in terms of the accuracy and precision that will progressively improve as the data collection, and our understanding of its interpretation, proceeds. Nevertheless, they are extremely heartening in terms of what they already show and what they promise for the future. It is clear that we are entering a whole new realm of analysis in terms of the care and subtlety required to pursue inference from data with such high frequency resolution and low noise.

The GONG Project was undertaken to test models of stellar structure. It appears that the adiabatic stratification in the Sun penetrates more deeply than in the Standard Solar Model. Part of the difference in u (= p/p) between Sun and model could be associated simply with the fact that the model convection zone may be too shallow. However, the excess u caused by that effect is of lesser magnitude than that found, and extends more deeply. A small increase in u between 0.3 Rsun and 0.6 Rsun might be accounted for in this manner, but a relatively substantial, localized bump between 0.6 Rsun and 0.7 Rsun cannot. The decrease in u immediately beneath the convection zone may arise from the accumulation of helium (which augments the mean molecular mass) which has been overestimated in the reference model. The bump could in principle have been produced by an opacity error that drops abruptly to zero immediately beneath the base of the convection zone; such a fortuitous occurrence is unlikely. The discrepancy in the core is the third prominent feature. Most secure is the lower value of u between about 0.1 Rsun and 0.2 Rsun, which implies that the variation of u itself is flatter than in the model. Once again this would be a symptom of too steep a composition gradient in the model, which here has been produced by nuclear reactions. The density variation is consistent with this interpretation: the regions of relatively steep positive slope in 5p/p in the core and immediately beneath the convection zone imply that the magnitude of the (negative) gradient of density is too high in the model.

In addition to helioseismic inferences of the solar interior structure, GONG's measurements of the velocity of the solar surface are of interest for the measurement of its nearly steady motions—large scale flows and convection, as well as rotation—all of which are thought to play important roles in generating the Sun's magnetic field. The differential rotation stretches meridional magnetic field lines to form strong toroidal fields (field in longitudinal rings about the Sun's rotation axis). The meridional circulation transports magnetic flux and angular momentum across parallels of latitude and from one radius to another. The nonaxisymmetric convective motions also redistribute magnetic flux and angular momentum in more complex and subtle ways. The Sun's differential rotation is accurately determined from single GONG observations. The rotation profile with latitude agrees well with previous measures, but also shows a slight north-south asymmetry. Rotation profiles averaged over 27-day rotations of the Sun reveal the torsional oscillation signal: weak, 5 m/s, jet-like features, which are fairly broad (15° wide), associated with the sunspot latitude activity belts. The latitudes of these features (18° north and 22° south) are slightly poleward of the latitudes where sunspots were found during this period. The jets appear consistently in three different temporal averages.

Stay tuned, GONG is just getting going. 2. Acoustical Events as Source of the Global P-mode Energy

Stebbins and Goode (1987) studied phase change with altitude in Doppler velocities in one horizontal dimension in the p-mode band of frequencies and noted that these phase changes in certain temporally and spatially isolated events were much too large to be explained as (nearly evanescent, or phase-change-less) p-modes. Goode, Gough, and Kosovichev (1992) modeled these occurrences as traveling waves which are excited in impulsive acoustical events, and conclude that these events occur less than 200 km below the photosphere, and that many of the 5-minute modes are excited by them.

Rimmele, et al. (1995) studied three-dimensional velocity data derived from high-resolution observations and noted that the acoustical events occur preferentially in the intergranular lanes, and are associated with an extra darkening of the lane just prior to the maximum of the energy flux at the surface (the acoustical flux) in the traveling waves. They argued that the excitation of solar p-modes is closely associated with the cooling and collapse of the solar surface which follows convective overshooting—rather than arising from the drumming by the convective overshooting itself. They also demonstrated that the acoustical flux is comparable to the energy that is required to power the entire p-mode spectrum.

Rimmele, et al. (1995b) demonstrated an anticorrelation between the acoustical flux and the line-center intensity in a magnetically non-sensitive (g = 0) spectral line. Since moderate magnetic flux density enhances line-center intensity (Chapman and Sheeley, 1968; Solanki 1993), they conclude that acoustical flux is suppressed by magnetic field.

Strous (1996, work in progress) averages the characteristics of the largest 2,000 acoustical flux events in his data set and shows that the average acoustical event occurs off to the side of the intergranular lane, and that the lane apparently narrows at the height of the acoustical event. He also notes a significant residual 5-minute oscillation in the average velocity, which may point at a correlation between the occurrence of an acoustical event and the phase of the dominant p-mode(s) at that time and place, thus leading to a feedback loop in p-mode generation.

In summary, we now have strong indirect evidence that the acoustical events pump power into the p-modes. We are currently looking for direct observational evidence of this.

Chapman and Sheeley, 1968, Solar Physics, 5, 442 Goode, Gough, and Kosovichev, 1992, AstrophysicalJournal, 387, 707 Rimmele, Goode, Harold, and Stebbins, 1995a, Astrophysical Journal, AAA, 119 Rimmele, Goode, Strous, and Stebbins, 1995b, Proceedings SOH04, 1,219 Solanki, 1993, Space Science Reviews, 63, 1 Stebbins and Goode, 1987, Solar Physics, 110, 237

3. Chromospheric He I Observations: Looking for Solar Wind and Coronal Rain

Imaging spectroscopy with the NASA/NSO Spectromagnetograph at the NSO Kitt Peak Vacuum Telescope has been used to study dynamic events in the solar atmosphere. Recent work (Penn and Jones, 1996; Dupree, Penn, and Jones, 1996; Penn and Allen, 1996) has used line profile measurements of the He I 1083 nm absorption feature to study outflows, downflows, spicules, and oscillations high in the solar chromosphere. The He I absorption line is very weak (with a central depth of only a few percent of the intensity of the continuum), but data from the KPVT have been used to measure the asymmetry of the line profile (Dupree, Penn, and Jones, 1996). In the quiet Sun outside of coronal holes no line asymmetry was observed. But the line profile showed a blue asymmetry, consistent with an outflowing gas component, in large regions of coronal holes near the solar poles. The asymmetry varied with the cosine of the viewing angle, suggesting that the gas flow was radial on the Sun, with an outward velocity of 8 km s'1. Although there have been no previous observations of the solar wind outflow in the chromosphere, polar coronal holes have long been known to be a source of the high speed component of the solar wind. Some recent modeling of coronagraph data (Habbal, Esser, Guhathakurta, and Fisher, 1995) suggests that significant acceleration of this wind may occur at low heights, and these initial KPVT data may be measuring part of that acceleration. More work is in progress to follow up these early results.

In contrast to the broad outflow regions, redshifts in the He I line are observed in spatially compact features scattered across the whole solar disk. Time series observations (Penn and Allen, 1996) have shown that these downflow events undergo significant morphological changes during their lifetime, and often show large transverse velocities. The events have broad spectral line widths, indicating that turbulent or high temperature plasma is involved. It is not clear where the downflow material originates; is it a return of the previously discussed outflow? Is it associated with macrospicule eruptions? Or are these downflow events true condensation of hotter coronal plasma, perhaps a cool coronal rain associated with coronal loop interactions seen in higher temperature lines (Airapetian and Smartt, 1995)? These questions will be answered when data from the Solar and Heliospheric Observatory (SOHO) are combined with simultaneous KPVT observations to measure the dynamics of both hot and cold components of the coronal plasma.

Airapetian and Smartt, 1995, Astrophysical Journal, 445, 489 Dupree, Penn, and Jones, 1996, Astrophysical Journal, 467, L121 Habbal, Esser, Guhathakurta, and Fisher, 1995, Geophysical Research Let., 22, 1465 Penn and Jones, 1996, Solar Physics, in press Penn and Allen, 1996, Solar Physics, submitted

IV. DIVISION OPERATIONS

A. Cerro Tololo Inter-American Observatory

1. CTIO Telescope Upgrades and Instrumentation

CTIO's program continues to focus on upgrading and instrumenting our telescopes so that they remain at a high level of scientific productivity in an era of modern 4-m and 8-m apertures. The Gemini 8-m project is well advanced on Cerro Pachon, and it should have a modern 4-m companion in the SOAR telescope. Various NOAO/CTIO in-house projects will be coming on-line in the next 3-5 years, and we anticipate that CTIO technical and scientific resources will be used extensively in the SOAR (and possibly Gemini) instrumentation and commissioning. The combination of SOAR and the Blanco 4-m, and their instruments, will be configured as far as possible—through sharing arrangements between the 4-m telescopes—as a complementary observing system in support of work with Gemini.

4-m Upgrades A main focus in FY 1996 continued to be upgrading the performance and general maintainability of the Blanco 4-m Telescope. The addition of active optics, image analyzer, and careful thermal monitoring and controls over the past several years have been very successful, and delivered image performance has improved significantly.

The image analyzer has been in routine use at the Cassegrain focus during the year, which has allowed the active primary support system and careful collimation of the prime focus and secondaries to deliver optical images as good as 0.56 arcsec FWHM. During FY 1996 monitoring of the thermal environment of the telescope and dome has been extensive. Analysis of the data produced by the many temperature probes installed on the telescope and on the dome interior has indicated that heat sources in the dome and building interior are still significant; control and removal of these heat sources are being addressed. The primary-mirror cooling system is run for up to several hours each day to try to bring the mirror to within 0.5 degree of the estimated mean nighttime air temperature. The system is under computer control, and we are experimenting with the algorithm so as to improve the accuracy of the nighttime temperature prediction. The capacity of the cooling system has proven to be marginal during wintertime, and we are investigating ways to improve this. An air extraction system was installed to flush the primary mirror cell and chimney area during observing, which has also helped to maintain proper mirror temperature.

During this year, a 10-week shutdown of the 4-m was undertaken for several purposes: 1) to renovate the old control wiring and logic; 2) to test the servo performance to investigate guiding and tracking issues; and 3) to upgrade aspects of the TCS and computer control system. Most of the control wiring and logic for the 4-m was more than 20 years old. Not only was the performance well below today's standards, but it is no longer possible to get spare parts for basic elements such as encoders and drive servos. During the shutdown, the antiquated 4-m telescope control logic has been replaced with a modem programmable- logic-controller-based system, following the upgrades made to the KPNO 4-m several years ago. With the improvement of the optical quality of the telescope, tracking and guiding performance have become limiting factors on delivered image quality. During FY 1996 (and continuing into FY 1997) effort has therefore been devoted to studying and improving the servo systems performance. Initially this involved careful tuning of the existing servo system and the addition of filters and ramps in the servo loop, which has been accomplished in the shutdown. We have also begun a pilot project to replace the actual servo system itself, to provide a modem and maintainable level of performance.

Previously the telescope has tracked at a fixed rate in RA and not at all in Dec. A number of effects including misalignment of the polar axis, flexure, and refraction, result in position-dependent tracking rates. These terms are included in the pointing model. In order to improve the open loop tracking, tracking corrections are now being derived from the first derivative of the pointing model.

The Cassegrain instrument rotator is now being controlled via a Smart Motor Controller rather than manually. This will allow for example, the spectrograph slit to be set to the parallactic angle while the telescope is slewing to the target coordinates and the guide

10 probe is being moved to the position of a suitable guide star. The scope of the project was extended to include the handling of signals passed through the old MUX system such as the readout of the guide probe position, and control lines for the rotator mirror and the image analyzer. This has the laudable goal of eliminating the old CAMAC system, which has been a source of heat as well as an increasing maintenance problem.

Major Instrumentation Efforts A major feature of the program in the past year has been preparations for new instruments which are due to arrive in 1997-98. In collaboration with the Tucson IPG effort, we will be equipping the Blanco 4-m with: a) the Cryogenic Optical Bench (COB) with at least a 512 x 512 InSb array; b) the NOAO 8K Mosaic imager at prime focus; c) the Phoenix high- resolution IR spectrometer; and d) the Hydra/CTIO multi-fiber spectrograph. Thus within two years we should have a 4-m telescope with excellent image quality over a small field at f/14, mainly for near IR imaging and spectroscopy. In the optical, the wide-field aspects are emphasized with the Mosaic imager and Hydra spectrograph; the telescope will be able to deliver good image quality over a 45 arcmin field.

During the past year, work has started on a new 400 mm camera for the 4-m bench spectrograph. Most of the optical figuring has been finished, and the camera will be installed next year, for initial implementation with the Argus multifiber spectrograph. Remaining aspects of the spectrograph will be modified next year in preparation for the Hydra system, involving a change in collimator and detector, to accommodate the slower f/ratio in the change from the prime focus to Cass and the larger number of fibers (from 48 to 138). A SITe 2K CCD has been purchased and will be the detector for this system.

One of our top-priority projects has been the implementation of the new f/14 secondary mirror on the 4-m telescope. The goal is to make our IR instrumentation compatible with the KPNO 4-m (f/15) and Gemini (f/16). The new secondary is also being installed with piezo-electric actuators in place to make it "tip-tilt ready." This will give CTIO the only major ER tip-tilt capability in the southern hemisphere. This is the logical extension of the program to improve the imaging capability of the Blanco Telescope. The emphasis needs to be on the near IR (JHK) because this is where tip-tilt achieves the greatest proportional gains in image diameter for a 4-m telescope with good seeing. This will produce an important improvement in the performance of our near-IR instrumentation.

This project to implement the tip-tilt capability for IR imaging and spectroscopy and also for optical imaging began in FY 1995 and is now more than half complete. Some delays have occurred due to difficulties with the final figuring of the secondary; it will be installed in early September 1996. The guider box at the Cassegrain focus uses a dichroic or beam-splitter to feed light from a guide star through re-imaging optics to a fast CCD camera. The guider box will have a remotely controlled x-y stage for the guide camera, and eventually will offer remotely controlled selection between different dichroics and beam splitters. The fast CCD camera is an upgraded version of our existing CCD-TV acquisition cameras, and has been shown in lab tests to work at 700 Hz for small readouts, with acceptable noise performance. The project includes a significant software effort to make the system efficient to use for visiting astronomers. The guider box and fast CCD are scheduled for engineering tests on the telescope in October-November 1996. The principal remaining work (which will carry over into FY 1997) will thus be software, user interface, and integration of the tip-tilt system.

11 This tip-tilt focus will feed the Cryogenic Optical Bench (COB), which is being upgraded by the Tucson IPG with a InSb array with at least 512x512 usable pixels. COB is scheduled for engineering tests on the Blanco Telescope in early FY 1997. In preparation for COB, cryocoolers and associated plumbing are being installed in both the 4-m and in the La Serena laboratories.

CCD Implementation and Arcon Controller Development Implementation of CCDs on our telescopes and the development of the Arcon controller continued to be a central part of our optical instrumentation program this year. All of our detector systems are now under Arcon control and continue to work reliably; our ancient VEB CCD controllers were finally retired this year. Two new CCDs were implemented:

•A thinned Loral 1200 x 800 CCD was successfully commissioned on the spectrograph of the 1.5-m telescope. This chip replaced a small-format, thick, GEC CCD, and the resultant throughput gains are more than a factor of two. It has been in routine use throughout the year.

•A SITe 2048 x 2048 CCD (with two good amplifiers) was purchased, eventually to be used for the Hydra spectrograph. It will be used initially as an imaging system (thus we will have four 2K chips running, including the STIS on the Schmidt), and then will be dedicated for use with the Argus/Hydra spectrograph. First science use is scheduled in September 1996.

During FY 1996 a major effort has gone into production of the five Arcons needed for the NOAO 8K Mosaic Imager system; this integrated hardware and software effort is finishing now, and the system should be delivered to Tucson in September 1996. Several engineers and scientists from CTIO have participated in engineering runs at KPNO in May, June, and September 1996 as part of this project.

During the Arcon development work over the past year, hardware and software upgrades have allowed a speed improvement of more than a factor of two, and current systems on Tololo are capable of reading out a conventional CCD at 100K pix/sec/channel. For the Mosaic work, planned upgrades should allow a readout approximately twice this fast, or 200K pix/s/ch. We intend to begin retrofitting the existing ARCONS on CTIO with the final versions of three new controller electronics cards (Video, VTT and ADC), which have been developed over the past year.

Small Telescopes Our second largest telescope, the 1.5-m suffers from a poor thermal environment and several optical problems with the secondary mirrors. Ventilation doors have been designed and constructed for the 1.5-m dome, and are scheduled to be installed starting in October 1996. An array of 32 doors with a total area of over 500 square feet will be installed in the segments around the lower rim of the dome. A new project has been started to provide more stable secondary mirror mounts, with encoders to permit reliable collimation runs.

At the Schmidt, the long-awaited NFCCD mounting box, shutter/filterbolt and smart motor controller were integrated and installed. The Schmidt now joins the 4-m in having a fully automated focus from the Arcon user-interface, thus increasing observing efficiency. The 0.9-m now has the focus readout also via computer, with the focus motor control loop

12 scheduled to be closed near the end of September. The 1.5-m telescope is scheduled early next year for a focus readout upgrade.

The Save-the-Bits (STB) software and dedicated exabyte drives have been installed on the 0.9-m and Schmidt telescopes. STB, a completely automatic data archiver, was transferred to CTIO from the successful KPNO system. STB will be installed on other telescopes and for use with IR data systems during engineering runs occurring in 1996-1997.

Other Although Cerro Tololo and Cerro Pachon are still very dark sites, CTIO has become increasingly concerned with the growing threat of light pollution from neighboring cities and towns. Thus we have begun to collaborate with local officials as well as private industry to ensure that future lighting installations are as "astronomer-friendly" as possible. This program has concentrated on several fronts, including public information, consultations on street lighting installation in local towns, and a regional light pollution ordinance as part of a newly-created national environmental commission.

Following a meeting of the international SOAR consortium in Chapel Hill, North Carolina in August, the following press release was issued in Tucson in mid-October along with locally-tailored versions in Brazil, Chile, North Carolina and Michigan:

National Observatories to Get New Telescope through International Partnership The Tucson-based National Optical Astronomy Observatories (NOAO) announced today that they have entered into an international partnership to construct a new state-of-the-art telescope. The telescope will have a primary mirror 4 meters (160 inches) in diameter, comparable to that of the Mayall Telescope on Kitt Peak. The observatory will be located in the western foothills of the Chilean Andes. The facility will be operated by the staff of the National Observatories' Cerro Tololo Inter-American Observatory, with headquarters in La Serena, Chile, on the coast about 300 miles north of Santiago.

The new telescope will be designed with actively controlled optics to produce images sharper than those made by older generation 4-meter telescopes. The new WIYN Telescope on Kitt Peak is of similar design, with the primary mirror resting on a bed of dozens of computer-controlled supports. WIYN routinely produces the sharpest images of any ground-based telescope of its size. A small, rapidly deformable mirror can be added to compensate for the blurring of turbulence in the Earth's atmosphere. With that addition, the new telescope will be capable of producing images in deep red light from the ground that are as sharp as those of Hubble Space Telescope.

Astronomers will design the light-analyzing instruments to be operated remotely. Scientists and students in their labs at their home universities or at the NOAO Tucson Headquarters will then be able to carry out their observations on the telescope in Chile. The plan calls for several instruments to be mounted on the telescope simultaneously. A quick change capability will allow a wide variety of programs to be carried out during any observing session.

The astronomical consortium chose the Southern Hemisphere site for several reasons: The site has dark skies and clear, dry air. The location is near the large, existing Cerro Tololo observatory and the new Gemini 8-meter telescope, now under construction and managed by another international consortium based in Tucson. The Southern skies offer astronomers

13 the additional viewing advantage of our nearest neighbor galaxies, the Magellanic Clouds, the center of our Milky Way Galaxy, and the brightest nearby stars. Many of these regions of the sky are not accessible to existing telescopes situated north of the equator.

The telescope facility will be named SOAR, the Southern Observatory for Astronomical Research. The international partnership consists of the US National Optical Astronomy Observatories (NOAO) supported by the US National Science Foundation, the country of Brazil, the University of North Carolina, and Michigan State University. The total project cost is 42 million for constraction and operations. Astronomers are planning for the SOAR telescope to be up and running within five years. NOAO will get about 1/3 of the time on the SOAR telescope. Astronomers throughout the US will compete for that time on the basis of project proposals. Astronomers from Chile will also get time on SOAR because the country provides access to the excellent site.

An English-language Web page is being set up in Tucson for SOAR. Look under the NOAO home page: http://www.noao.edu/ and click on SOAR (in the list of NOAO Observatories and Telescope Projects).

2MASS at Cerro Tololo 2MASS is a project to carry out an all-sky infrared survey with 2.0" pixels to 10-sigma limiting magnitudes of J = 15.8, H = 15.1 and K = 14.3. The sole existing large-area survey in the near infrared, the Two-Micron Sky Survey, reaches only to 3rd magnitude, covers just half the sky, and contains 5600 objects. With the 25,000-fold sensitivity improvement, 2MASS is expected to catalog 100 million point sources and hundreds of thousands of galaxies and other extended objects. Near-term scientific objectives include the study of Galactic structure via IR luminous stars visible throughout the galaxy, galaxies in the local universe (imaged at wavelengths that characterize their underlying mass distribution), and searches for rare objects such as brown dwarfs. Since the most exciting applications of the 2MASS database will probably be unforeseen ones, the Project team has a strong commitment to making the completed Survey data available to the community without a lengthy proprietary period.

Two telescopes of 1.3-m aperture are being constructed to carry out the survey—one will be installed on Mount Hopkins, the other on Cerro Tololo. The project is being managed by a group at the University of Massachusetts, with the data product to be produced by the Infrared Processing and Analysis Center at Cal Tech. CTIO is acting as a contractor for construction on the Tololo site, and will play some contract role in operations as well.

On 14 May CTIO scientific, engineering and administrative staff members met with the UMass Project Manager to decide the most desirable site location for the southern 2MASS Telescope, explore practical construction solutions, and discuss the future operation of this telescope on CTIO. These meetings were later complemented with a visit to the designated telescope construction site just below the GONG site above the North-East face of Tololo.

A month later, on 14 June, CTIO presented two proposals for the construction of the enclosure and the control room (designs prepared by CTIO and 3M Engineering). UMASS opted for the CTIO version, which uses reinforced concrete for the enclosure and brickwork for the control room. We are currently working on the civil engineering design detail and statement of work concepts. Construction work began on the site in September.

14 An outline description of the project and more information (so far mainly about the identical northern telescope on Mount Hopkins) can be found at: http://pegasus.phast.umass.edu/2mass/telescope.html.

2. Facilities Operations

This year the CTIO budget was once again afflicted by financial constraints that seem to have become a permanent feature of our operations. This condition was further aggravated by the fact that the budgeting levels wereunknown until we were well into the fiscal year.

Certainly the most distressing result of these budget cuts was the formal Reduction In Force in March, when approximately 12% of the Observatory workforce was laid off, culminating in a series of observatory-wide staff reductions totaling more than 20% over the last three years.

Following is a summary of the main activities performed in the Administrative Services and Operations Division during the FY 1996.

Logistics and Administration Reduction in Force (RIF) The loss of 16 people from Operations and Administration in less than 12 months has brought with it the need to make a number of radical changes in the management strategies of CTIO. The most relevant change was the merging of the Administrative and Operations Divisions, in order to provide for a more efficient use of CTIO's shrinking manpower

resources.

IVA (Value Added Tax) Refund Procedures AURA has continued to exercise its prerogatives granted by Law Decree 560 of 18 June 1985, whereby it can request from the Chilean Treasury Department the reimbursement of IVA Tax paid by CTIO. In the past these presentations were submitted at irregular periods; a more efficient strategy has been implemented in which refund claims are presented to the government comptrolling agencies on a monthly basis.

Information Service Upgrade - Phase I: Hardware The quality of the Information Services in Administration has suffered for several years now. These problems originated mostly in the choice of inadequate technologies, archaic software, shortage of resources, and lack of a coherent plan to provide the observatory with reliable business information services.

Upgrading of the Administrative LAN hardware is now underway. Completion of the first stage of this project is expected to occur during the first quarter of FY 1997; in addition to upgrading current access, the LAN will incorporate crucial additional stations located in Santiago, Cerro Tololo, and La Serena.

The next step is to replace the old administrative computer software with modem and efficient applications that will contribute to increase the quality, availability, and timely reception of the information that Administration originates. The local market offers software applications for the Chilean environment to improve the Accounting, Payroll, Warehouse and Personnel modules' efficiency, with the added benefit of an array of

15 analysis and report tools to provide the means for increasing the soundness and quality of financial controls.

Blanco 4-m Telescope - Fire Prevention The first stage of the installation of a modem fire detection and alarm system for the Blanco Telescope has been completed. The second phase of this project is underway and involves the installation of control mechanisms that will automatically shut off all ventilation equipment and shutters in the event of a fire, thus preventing potential contamination from gases and fumes that might otherwise escape and spread throughout the building. Funds permitting, we plan to install an automatic fire-fighting system for unattended areas of this telescope.

In addition to the above, our personnel continue to be trained in modem fire-fighting programs and fire prevention techniques.

La Serena Water System During the month of March the installation of a new industrial-type water filter for the water distribution system in La Serena was completed. This 5 urn activated-carbon filter will completely eradicate particles, algae and other solids from the compound's drinking water.

Support ofthe Gemini Project in Chile Between 6-8 May, a delegation of NOAO and Gemini Management representatives met with CTIO management staff members in La Serena to identify future management and logistics requirements for the administration of the Gemini construction stage as well as for the subsequent operational phase. During the course of these meetings the critical need for common strategic administrative information systems, in order to seek full data compatibility between Gemini, NOAO, and CTIO, was addressed.

Gemini assigned CTIO Logistics and Administration Division the responsibility of conducting negotiations with the Irrigation Department, regional mining concerns, the Public Works Ministry, and ultimately, with the Road Department, to reach an agreement for the enlargement of the Puclaro Road tunnel, in order to allow the passage of large cargoes of telescope components exceeding the width of the original tunnel design. Attempts to persuade local companies, which might benefit from an increased tunnel width, to join forces with us and seek financing for the enlargement of the tunnel proved unsuccessful. After a long and difficult negotiation, an agreement between the Road Department and AURA, Inc. (on behalf of Gemini) was reached whereby Gemini would contribute the incremental financing required to enlarge the width of the tunnel, in strict conformity with the requirements and interests of the project.

CTIO Operations personnel have been increasingly involved in assisting Gemini with the logistics and administrative management of incoming ocean cargo consigned to the project operations in Chile.

The Cerro Pachon road improvement was successfully completed, as specified by Gemini, to allow for the passage of loads of up to 10 mts. wide.

16 2MASS On 14 May CTIO scientific, engineering, and administrative staff members met with the 2MASS Project Manager to decide the most desirable site location for the southern 2MASS telescope, explore practical construction solutions, and discuss the future operation of this telescope on Cerro Tololo. These meetings included a visit to the telescope construction site.

The University of Massachusetts accepted CTIO's proposal for the construction of the enclosure building and control room for their telescope. This construction is expected to be completed in December.

Robotic Camera On 21 June a set of pictures, coordinates, and site plan drawings was sent to John E. Gaustad for the installation of a Robotic Camera on CTIO. The installation schedule for this instrument has been set for 11 October 1996.

B. Kitt Peak National Observatory

Both significant milestones and a critical failure marked FY 1996 for Kitt Peak National Observatory. The WIYN Observatory completed a most successful first year of science operation. The prime focus focusing mechanism of the Mayall 4-m was completely replaced during Summer Shutdown to enable the CCD Mosaic to be installed in fall 1996. The high resolution IR spectrometer, Phoenix, began commissioning and the Mayall 4-m was closed from 30 October to 27 December because of a catastrophic failure of the dome shutter gearbox.

1. New KPNO Programs in FY 1996

The WIYN Observatory began science operations in July 1995 (NOAO receives 40% of the time on WIYN to schedule and operate for the astronomical community) and in its first year has proven to meet its design goals and to enable excellent astronomical research. NOAO time on WIYN is primarily scheduled for the Queue Observing Experiment where KPNO support staff obtain observations for observing programs submitted to NOAO from the astronomical community. The goals of this mode of operation are to complete highly ranked proposals in a timely fashion, to provide new science opportunities by allowing a wider range of program lengths, and to develop observing processes applicable to the Gemini telescopes. In addition, the WIYN Queue is designed to match the observing program to the observing conditions so as to increase telescope effectiveness. The first semester—fall 1995—was very highly oversubscribed, reflective of the interest in the new scientific opportunity which WIYN provides, and the WIYN Queue had a steep learning curve to climb. As expected, the second semester—spring 1996—ran much more smoothly and more productively. During spring 1996 nights were divided between classically scheduled time, programs selected where it was advantageous to have the PI on site, and the Queue. The WIYN Queue will continue to be fine tuned and optimized in the future to maximize the scientific output (e.g., to provide scientifically useful partial data-sets when 100% program completion is not possible) and to define how queue and service operations should be ran on Gemini before Gemini operations begin.

WIYN has now been fully integrated into KPNO operations, both in day-to-day operations and maintenance and in improvement projects. An Operations Readiness Review (ORR) for

17 WIYN was held in February 1996 to review the as-built status of the telescope, instruments, and enclosure. The WIYN ORR panel generated a list of actions considered significant in bringing the observatory up to its full potential and to operate in a safe fashion. Many of these action items have been incorporated as future improvement projects for WIYN. The biggest challenge for WIYN is to achieve in a reasonable amount of time and resources a steady state level of reliable operation comparable to other KPNO telescopes.

The success of CTIO in improvement of image quality at the Blanco 4-m indicates that the "old" technology telescopes like the Blanco and KPNO Mayall can be improved to deliver better images—the Blanco now routinely averages sub-arc second images—if one is willing to spend the time and resources. Two significant programs were initiated in FY 1996 at the Mayall 4-m: to collimate the optics with wave-front curvature analysis and to begin regular (several times a night), systematic measurement of the delivered image quality (DIQ). WIYN aided in addressing an underlying question: is it worth the effort to make the Mayall better? Since WIYN is designed not to degrade the free atmosphere seeing conditions, the image size delivered by WIYN demonstrates that Kitt Peak is a much better site than previously thought. Between September 1994 and June 1996 the average DIQ at WIYN was 0.8 arcsec, with 24% of the time better than 0.7 arcsec and 11% better than 0.6 arcsec. For several months in spring 1996, the average measured DIQ at the Mayall 4-m was 1.1 arcsec. The poorer DIQ at the 4-m relative to WIYN can be attributed to the effects of turbulence in the dome and adjacent to the mirror and to optical collimation. As a part of Summer Shutdown 1996 activities the primary mirror support system was refurbished and a careful end-to-end alignment of the optics carried out. For several nights before resuming operations the DIQ was measured at both the 4-m and WIYN at essentially the same time and under optimal conditions where there was no mirror or dome degradation of the 4-m DIQ. Within the precision of measurement and seeing variability, the measured DIQ was exactly the same at both sites, indicating that under these circumstances the Mayall delivered essentially site-limited seeing. The goal for FY 1997 is to decrease the average DIQ and to increase the number of nights when excellent seeing conditions are achieved because the free atmosphere seeing is better than average (e.g., less than 0.7 arcsec).

2. KPNO Observing Improvements

Improvement projects this year were severely set back by the catastrophic failure of the dome shutter gear assembly.The root cause of the failure was wear over thirty years of use. The original gears were cast-iron with a hardened surface. When the hardening wears through, rapid wearing of the gears occurs with the teeth then easily breaking. All of the gears showed pitting from wear, an indication of surface fatigue failure, but without signs of scoring, which would indicate oil film failure due to excessive loads or aging lubricant. All of the bearings in the gearbox showed similar wear and were replaced. The new gears are made of solid steel with wear properties superior to cast-iron. In addition, the two original motors—one for slow speed and one for fast—were replaced with a single DC motor that ramps up to the set speed, thus placing less load on the gearbox when starting and stopping. All astronomers affected by the closure were informed of the schedule for repair and asked when they would like to be re-scheduled. By shortening the block assigned for DLIRIM proposals, two canceled programs were scheduled. Five proposals canceled in the fall were scheduled in early spring 1996. The remainder were given special consideration for fall 1996.

18 Essentially all major improvement projects and summer shutdown activities in FY 1996 focused on the Mayall 4-m telescope. The prime focus mechanism (the "pedestal") and ancillary electronics were completely replaced to support the Mosaic CCD imager. As usual, all guiders and filter wheels were inspected, cleaned, and aligned, IRAF and computer operating systems were brought up to the latest releases, and CCD dewars cleaned and freshly evacuated with CCDs flooded for ultraviolet sensitization.

The multi-slit entrance masks for multi-object spectroscopy with the R-C Spectrograph or Cryogenic Camera at the 4-m have been made from photographic film with a 10% throughput loss in the film-base material. We have now developed a new technique using thin etched stainless steel for the mask material which has zero throughput loss, effectively increasing the speed by 10%. Other deficiencies corrected by this adaptation of integrated circuit technology are occasional scale errors due to drifts in the film recorder electronics and internal fringing in the film base.

Because oversubscription for imaging at the Mayall 4-m and at WIYN means that many requests for moderately high resolution optical imaging must be rejected, imaging was made available at the 2.1-m starting in fall semester 1996 with a Tektronix 1024 x 1024 CCD (TIKA). The ILS camera system, which replaced the venerable IDT guider as part of making the 2.1-m user-friendly for astronomer operation, has been upgraded with a neutral density filter and remote focus for efficient operation with imaging. The demand was quite high for imaging at the 2.1-m with 32 nights scheduled in fall semester 1996.

The high demand for CCD imaging with the Burrell Schmidt during both KPNO and CWRU time has resulted in the decision to offer only a CCD as a detector; photographic plates will no longer be an option. Consequently, the opportunity arose to remove the plate holder hardware which obstructs a significant fraction of the incoming starlight. Tests indicate that a throughput gain of 60% was achieved. At the same time the lead screw in the CCD focus mechanism was replaced to reduce sky-position-dependent focus variations and a new collimation technique developed. The resulting images were less than two pixels over the entire chip, i.e., under-sampled.

3. KPNO Instrumentation Improvements

Kitt Peak CCD controllers have used 15-bit analog-to-digital converters for many years with a dynamic range of 32,767—a dynamic range which requires some compromises between using all of the linearity range of the CCD and fully sampling the readout noise. A related problem concerns the effects of saturated stars on the CCD electronics and on the resulting data. While we have in recent past optimized the electronics for the gain which minimizes these effects, a higher digitization limit would achieve a better compromise of larger dynamic range and better sampling of the readout noise. With the start of the fall 1996 observing schedule, all of the KPNO CCD controllers now have 16-bit A-D converters that allow either twice the dynamic range or two times better sampling of the read noise at the previous dynamic range. An added benefit is that the new A-Ds operate faster, and some 16 seconds will be trimmed from every 2048 x 2048 CCD readout. While this does not seem a lot of time, the 16 seconds faster readout translates to an hour per night over the various KPNO telescopes and 5-10 nights worth of telescope time over the course of a year.

19 New imaging correctors to accommodate the 8K x 8K CCD Mosaic Imager were designed and constructed for the 0.9-m and 4-m telescopes. The 0.9-m corrector, a simple doublet of fused silica, with the Mosaic imager enables observations of a field 59 arcmin square with 0.43 arcsec pixels. The 4-m corrector, which includes atmospheric dispersion compensation, with the Mosaic imager provides a field of view at the Mayall Prime Focus of 36 arcmin square with 0.26 arcsec pixels. Both correctors are designed to maximize transmission in the ultraviolet and to minimize scattered light. The correctors were designed to produce spot sizes less than a single pixel over the whole field, and on- telescope tests indicate that off-axis images are not degraded by the corrector.

The new high-resolution IR spectrometer, Phoenix, has begun commissioning on the mountain. With an instrument the scale of Phoenix—it is larger and more massive than other IR instruments—a number of small, but significant improvements were required to the 2.1-m telescope and facility. All of these have been completed and Phoenix will begin a special opportunity observing process in the fall 1996 Telescope Schedule.

C. National Solar Observatory

1. Kitt Peak

The McMath-Pierce Solar-Stellar Spectrograph The community has made available resources from individual grants in order to renew the nighttime program with the solar-stellar spectrograph. Nighttime operations at the McMath- Pierce facility will resume by the beginning of FY 1997. A resident observer will obtain synoptic observations with the solar-stellar spectrograph. The mix of scientific programs based on the contributed funding includes both solar-system studies and solar-stellar investigations. In addition, approximately 30-40 nights of synoptic time will be available to the general solar-stellar community on a competitive proposal basis.

The program was terminated in 1995 before the new cross-dispersion system could become fully operational. The solar-stellar spectrograph will therefore continue to operate in a single-order mode using the TI 800 x 800 CCD. We are still pursuing the possibility of replacing the current CCD with a large-format (1Kx3K) device from the NOAO instrumentation program. Thus far, ultra-thinned devices that may be unaffected by the resolution degradation problem of the other 1Kx3K arrays have not been successfully produced. Array development and testing continues.

Digital Library Development During FY 1996, NSO began to populate its 300-disc CD-ROM jukebox with data from the FTS and the KPVT. Currently, the jukebox holds a complete set of 39 discs of FTS transformed spectra, eight discs of 512-channel magnetograph data, and three discs of spectromagnetograph data, for a total of about 35 GB of on-line storage. The jukebox is already being heavily used, with over 2000 files transferred in the period of 11 April-3 August 1996 in spite of the fact that there is no useful on-line search engine. The development of the NSO Digital Library will accelerate in FY 1997. The addition of resources from the NSF Space Weather Program and the NASA Space Physics Data System will speed up migration of the data into the jukebox, and allow progress to be made

20 on a search tool and user interface. These improvements will further reduce both the delay in the delivery of data to users, and the impact on scientific staff time to fill data requests.

NIM-2 (Near Infrared Magnetograph) The NIM-2 project is constructing an imaging vector magnetograph based on a piezoelectrically-tuned, servo-stabilized Fabry-Perot etalon. The existing Near Infrared Magnetograph maps the true magnetic field strength in the deep solar photosphere, using the McMath-Pierce Telescope, the 13.7-m vertical spectrograph, a liquid crystal polarimeter, and an infrared array camera that records two Zeeman-sensitive iron lines near 1565 nm. Using the same infrared camera with an improved polarimeter and data system, NIM-2 will achieve better time resolution and geometric stability (because the field of view is imaged simultaneously rather than built up by scanning) with little sacrifice in spectral resolution.

The project made major strides in FY 1996 and is ahead of schedule. The Fabry-Perot etalon and the prefilter were received and tested. The mechanical and optical designs were finalized. Mechanical fabrication is complete. The optics have been delivered and installed, although they will be sent out for coating after the first-light tests. A fast liquid crystal modulator was received which meets the primary switching-speed requirement but is being reworked for ancillary improvements. The camera readout system has been modified to almost double the exposure duty cycle. First light was achieved during August, and NIM-2 will be commissioned during FY 1997. The NIM-2 project is partially supported by a grant from NASA.

Large-Format IR Array Camera The McMath-Pierce facility offers capabilities that are unique in the world for infrared solar observations: an unobstructed, all-reflecting light path (giving full wavelength coverage with low thermal background) and large aperture (for angular resolution and photon flux). These capabilities cannot be fully exploited without a state-of-the-art infrared array detector at the focal plane.

The present detector is a commercial 256 x 256 InSb array from Amber Engineering, re housed in a dewar from Infrared Laboratories. We chose this system because of its low initial cost and 1-5 urn wavelength coverage. It has succeeded in jump-starting magnetic observations with NIM and enabling a new class of results from CO spectroscopy. However, the Amber system is becoming obsolete (this only takes 3-4 years in the realm of infrared technology).

NSO plans to replace the Amber array with a state-of-the-art 1-5 urn camera by taking advantage of NOAO's investment in the Aladdin array development project. The performance of an Aladdin-based system will surpass the Amber system in every important respect (dark current, readout noise, quantum efficiency, and immunity from electronic interference); its 15-20 Hz frame rate is well matched to the requirements of NIM and NIM-2.

During FY 1996, NSO prepared the way for the Aladdin era by purchasing a closed-cycle cryogenic cooling system and proving it in use by hosting KPNO's Simultaneous Quad- color Infrared Imaging Device (SQED) at the McMath-Pierce. During FY 1997 we will take the next step by hosting the Aladdin-based Phoenix instrument for solar infrared

21 spectroscopy. Also during FY 1997 NSO will purchase an Aladdin controller from NOAO/TPG, which has undertaken to produce a controller for NSO during FY 1998. Our program assumes that NOAO will provide one or more science-grade Aladdin arrays without cost to NSO.

Kitt Peak Vacuum Telescope Control Upgrade FY 1996 was the second year of a long-term project to upgrade the 23-year-old control and guiding systems of the KPVT. Maintenance of these systems is becoming difficult since many of the components are no longer available. Performance problems also limit the quality and quantity of data from the focal plane instruments.

The overall goals of the project include better control of image guiding and scanning, reduction of unwanted image motion, replacement of obsolete computerized control systems, and computer control of the Littrow spectrograph. The overall upgrade plan is divided into small, stand-alone segments that provide prioritized, incremental improvements.

To date, new gear boxes and motor drivers for the drive system of the No. 2 mirror have been installed. These have greatly reduced the amount of backlash and improved the reliability of these drives. A mounting and solenoid drive that will allow the No. 4 mirror to be rapidly tilted to reduce image motion has been constructed and tested. It is scheduled for installation in September 1996. The overall computer software and hardware architecture to be used to control the telescope has been specified. A design for new sensors to replace existing limb guiders and supporting electronics is underway. The design activities are intended to be transferable to similar upgrades planned for the McMath-Pierce Telescope and the proposed SOLIS project.

Milestones

FY 1995 - Design and start manufacture of new No. 2 mirror drive mechanical and electronic systems. Design fast tip mounting for No. 4 mirror. Start electronic design of No. 4 mirror drivers. Status: completed.

FY 1996 - Complete the fabrication and installation of the upgraded mechanical drive assemblies on the No. 2 mirror. Complete the fabrication and installation of the mechanical components of the image-motion compensation. Start the design and fabrication of the image-motion compensation electronics. Start the design of the guider control electronics and software. Specify the architecture of the telescope control software and hardware. The bulk of the computer hardware required to complete the upgrade will be purchased in late FY 1996.

FY 1997 - Complete the installation and testing of the image-motion compensation electronics. Complete the installation and testing of the guider control electronics and software. Complete computer control of the Littrow spectrograph.

22 2. Sac Peak

Mark II Correlation Tracker The development of the Mark U correlation tracker (CT) at NSO/SP has been mostly finished during FY 1996. The CT system was integrated from off-the-shelf hardware components, will be easily maintainable, and can be cloned for use at other observatories. A tip/tilt mirror system, purchased from the Kiepenheuer Institut fur Sonnenphysik using Air Force Phillips Lab funds, was integrated into the system as a corrective element. The servo loop was successfully closed in a test setup in the optical laboratory and the performance of the CT system was characterized. The CT will see first light at the Vacuum Tower Telescope (VTT) in September 1996. We anticipate that a minimal software effort will be required in early FY 1997 in order to integrate the CT as a user-friendly instrument into the VTT system. A permanent optical setup, that allows for easy alignment and calibration of the CT was also installed during FY 1996.

Fast CCD Cameras We are working toward replacing the custom-built MDA detector system with state-of-the- art, large format CCD detectors. A Thomson IK x IK camera with 10-bit resolution and a frame rate of up to 5 frames/sec and a KODAKMegaplus, with a 1317 x 1035 pixel format and 8-bit resolution running at 6 frames/sec, are now available at NSO/SP. These cameras can be used for high speed imaging and frame selection. A 2K x 2K 12-bit camera has been ordered from Xedar. The prototype of the 2K x 2K CCD, developed for the RISE project, has been delivered and is currently being tested and evaluated at NSO/SP. A second 2K x 2K camera will be delivered to NSO/SP in October 1997. Additional 2K x 2K CCD detectors will be added as funds become available.

Image Quality Improvement at the VTT In FY 1996 the optical performance of the VTT was measured, both by Shack-Hartmann wavefront sensing using sunspots and stars as targets, and by interferometry. The results show that the image degradation arising from the telescope alone can be worse than that caused by atmospheric seeing at Sac Peak. Earlier work showed that solar heating of the entrance window and its cell, which predominantly affects the edge of the window, produces time-varying spherical aberration and higher order circular modes in the wavefront. These effects have been studied in detail using interferograms made by combining laser light reflected from the two sides of the window. Besides the circular modes caused by the heated edge, these measurements also show considerable astigmatism that may be temporarily variable, as well as some coma.

The thermal effects on the wavefront due to heating of the window have been greatly reduced by an active cooling system that senses the gradient of temperature both across the face of the window and through its 4-cm thickness by combining the measurements from pairs of sensors on the outside and on the vacuum side of the window. The error signal for the servo is derived by comparing the average of one pair of sensors at the edge of the window to another pair 10 cm in from the edge. Interferograms show that the window figure errors have been reduced from several waves to a fraction of a wave, implying that the window temperature is now uniformly maintained to a few tenths of a degree. The performance of the VTT has been significantly improved by this: frame selection procedures now achieve diffraction limited resolution.

23 A Shack-Hartmann WFS was used to measure the aberrations of the entire telescope, including the entrance window. Comparison of the wavefront errors produced by the window alone to the overall wavefront measured with the Shack-Hartmann showed that a significant portion of the image degradation coming from the telescope does not arise in the window. Subsequent tests of the two 1.1-m diameter Cervit turret mirrors using a Ritchey- Chretien test set up with a 1.27 meter aperture sphere on loan from the KPNO optical shop showed that the edge of one of the Cervit mirrors is turned down by at least two waves. This mirror is being resurfaced and should be back in the telescope by the end of FY 1996.

Active Optics Further improvement of the optical performance of the VTT can be achieved by using a deformable mirror aimed at correcting fixed and slowly-changing aberrations. A relatively slow system with a bandwidth of a fraction of a Hz, using a Shack-Hartmann wavefront sensor with a limited number of subapertures, is faster and less costly to implement than a high bandwidth adaptive system aimed at full atmospheric compensation. Such an "active" optics system is currently under development at Sac Peak, based on a 97-actuator Xinetics mirror purchased with USAF and NSO funds. This active optics system is regarded as a stepping stone to the more elaborate adaptive optics system that has been under development at Sac Peak for a number of years. Not only should it further improve the performance of the VTT on an interim basis, but also it will provide experience and insight into solar-related AO problems, such as wavefront sensing using solar granulation. In FY 1996 a first successful active optics experiment was performed at the VTT in collaboration with the Lasers and Imaging (LI) Directorate of the Air Force Phillips Lab/Albuquerque using a 127-element LCD wavefront corrector provided by LI in conjuction with the Hartmann-Shack wavefront sensor developed at NSO/SP. The active optics development will continue through FY 1997.

Adaptive Optics Since the successful demonstration of the Lockheed 19-segment adaptive mirror at Sac Peak in 1991, there has been pressure by the users to build a facility AO system for the VTT. Technical problems and lack of personnel have slowed the realization of this goal. Progress has been made in all aspects of the supporting optical system, and much of the optics for the innovative LCD wavefront sensor is in place.

The wavefront sensing problem in solar adaptive optics is more difficult compared to nighttime AO because no point source is available on the solar disk. A solar wavefront sensor has to function with solar granulation, an extended low-contrast scene. NSO is using a 640 x 640 pixel thin-film transistor LCD display to create a spatial mask for filtering the granulation scene and thereby encoding wavefront slopes as intensity variations at the detector. The concept is not unlike the "knife-edge" or Foucault test, the generalizations being that the edges are placed over intensity features (granules) everywhere in a scene, and that the mask is dynamic, being updated as the granulation pattern changes. Because the LCD display is large, the wavefront sensor optical system is placed in one of the large instrument vacuum tanks in the VTT.

The NSO efforts during FY 1996 were concentrated on validating this wavefront sensor concept and comparing its performance to the modified Shack-Hartmann wavefront sensor. Evaluating and understanding the wavefront sensor is a crucial milestone to be achieved by early FY 1997.

24 A second milestone for FY 1996 was achieved by finishing the mechanical and electrical assembly of the 61 actuator continuous faceplate mirror.

Infrared Program NSO/SP maintains two near-IR camera systems which were developed by outside collaborations (with Michigan State University, Wyoming Infrared Observatory, and Haverford College). These cameras account for about 25% of the user time allocated at the VTT and the Evans coronagraph. Some year-end funds were allocated last year for IR optics and the purchase of an IR array. During the coming year we will develop a 1-2.5 um camera system that is available year-round at NSO/SP. The system will be developed in collaboration with MSU and Starfire Optical Range, Albuquerque.

In collaboration with the USAF, we have obtained two near-IR Fabry-Perot etalons and an additional controller. The etalons will be used in tandem for narrowband imaging between 1-1.8 um. Current projects include: coronal imaging in 1083.0 nm, velocity and magnetic field maps of the corona, and development of a prototypeimaging vector magnetograph for possible use in an upgrade of the AF solar observing network. The etalons will be available for user programs during 1997.

D. US Gemini Program

The US Gemini Program (USGP) serves as a liaison between the International Gemini Project Office (IGPO) and the US community. The Gemini Project is an international consortium to build two 8-m telescopes, one on Mauna Kea, Hawaii, and one on Cerro Pachon, Chile, in which the US maintains a 50% share. The USGP is led by the US Gemini Project Scientist, and currently includes one Astronomer, a Project Engineer, and a Technical Administrator.

A major part of the work of the USGP during the past year has been connected with procurement of the Gemini instruments assigned to the United States. The United States is responsible for three instruments, a near-IR (1-5 um) imager, a near-IR spectrograph, and a mid-IR (8-30 um) imager. The near-IR imager was assigned by the NSF to the University of Hawaii; the USGP is responsible for the procurements of the other two instruments. The near- IR spectrograph was assigned to the NOAO instrumentation group through a competitive selection in FY 1995. The mid-IR imager is still in the selection process. At the request of the IGPO, the USGP has taken on the management of these instruments as the Gemini IR Instrument Program. This approach allows one group, the USGP, to look out for interface issues, areas of commonality among instruments, and to identify and help to solve problems in areas of budget, schedule, and risk.

During FY 1996, the USGP defined a plan for the procurement of the mid-IR imager, involving a two-stage competitive selection open to the entire US community. The first phase of this was a competition for an award to conduct a conceptual design study. This was carried out in FY 1996, and negotiations are underway with two groups to do this work. This work will be completed in early 1997 and will be followed by another open competition to produce a detailed design and fabricate the instrument.

In addition to these instruments, the United States has been asked to provide the optical and infrared detectors and controllers for the Gemini instruments. The USGP has been monitoring

25 development programs at a number of CCD vendors, and a plan for procurement of these and the CCD controllers is being finalized. The specified near-IR arrays are the 1024 x 1024 InSb ALADDIN arrays being developed jointly by NOAO, the US Naval Observatory, and the Santa Barbara Research Center. The USGP has worked with the NOAO instrumentation group and Gemini representatives to develop a plan by which a foundry ran following the ALADDIN effort will provide Gemini with the detectors it needs.

After the selection of a supplier for each instrament is made, the USGP remains responsible to the Gemini Project in seeing through the successful design, fabrication, and delivery of each US-allocated instrament. This activity includes day-to-day monitoring of progress by each of the instrament suppliers, identifying concerns that have implications for cost, schedule, or risk, and helping the groups work out solutions to these concerns. During FY 1996, USGP personnel worked with the University of Hawaii near-IR imager group to develop a realistic schedule and management plan for that instrament. USGP staff have coordinated discussions and testing of common aspects such as cryogenic motors, software, and on-instrament wavefront sensors. The USGP works with the Gemini Project in organizing and conducting design reviews and acceptance tests.

In August 1996, the USGP organized a workshop on the US interests in future instruments for the Gemini telescopes. The discussion was focused on the science that the community will want to do with the Gemini telescopes and in the context of the entire suite of facilities available to the US community. About 25 astronomers from around the country participated in this two-day meeting in Tucson. Major elements of the plan endorsed by the group are an aggressive adaptive optics program, ultra-high resolution optical spectroscopy, and Near-IR spectroscopy with spatial multiplexing, either with multiple slitlets or with an integral field feed.

In order to encourage a better understanding of the Gemini capabilities by the South American partners and to foster collaboration between southern hemisphere and northern hemisphere Gemini partners, the USGP organized and carried out a Gemini workshop at the 7th Regional Latin American Astronomy meeting held in Montevideo, Uruguay in November 1995. This workshop included a Gemini display, a session of talks on the Gemini telescopes, instrumentation, operations plans, and a question and answer session. The meeting was attended by a number of astronomers and national project office staff from the US, the UK, and Canada.

The USGP is responsible for keeping the community informed about Gemini's progress and fostering community support for Gemini. Displays are regularly presented at AAS meetings and USGP staff contribute status information to both NOAO and Gemini newsletters. The USGP is also in the process of developing a World Wide Web site to provide all the information and support that US astronomers will need to use the Gemini telescopes effectively.

Another USGP responsibility is the monitoring of technical developments within the project. The US Gemini Project Scientist serves on the Gemini Science Committee (GSC) and represents there the views of the US scientific community. In addition to the GSC and project scientist team teleconferences, formal input is contributed through participation in reviews and working group meetings organized by the project. The USGP also solicits membership for US participants in these reviews and meetings and organizes the US participation in the GSC. One such meeting held in May 1996 was a scientific review of the High-Resolution Optical Spectrograph (HROS), an echelle spectrograph being designed in the UK for the southern Gemini telescope. A group of four US astronomers participated in a two-day meeting at

26 University College London where they helped to define the performance requirements for this instrament. HROS is now proceeding toward a conceptual design review late in 1996.

In a similar way, the national project managers meet regularly to discuss procurements and other management issues. USGP staff take part in these discussions, and the US Project Scientist represents US issues in these matters at semi-annual national project managers' meetings and the Gemini Director's review.

In a less formal sense, the USGP personnel interact frequently and directly with the Gemini Project to provide scientific and technical feedback, to identify scientific performance issues and to help define technical solutions to meet the science requirements, to evaluate implementation plans, and to participate in source selection for critical systems and components.

The USGP has participated intensively in the development of a plan for the evolution of responsibilities in the operations phase of Gemini. It is clear that the international Gemini Office will continue to depend on the national Gemini offices for a great deal of assistance in interacting with the user communities of the partner countries. The national Gemini offices will solicit proposals, perform technical evaluations, run national time allocation committees and national users committees, and will provide assistance to astronomers in writing Gemini proposals and reducing Gemini data. The USGP has begun to plan for these activities as well as other possibilities such as providing a remote observing center and developing tools to support queue observing with Gemini.

E. NOAO Instrumentation Program

The purpose of the Instrament Projects Group (IPG) is to develop and produce major instruments for the NOAO nighttime telescopes at both CTIO and KPNO. The NOAO scientific staff initiates, directs, and prioritizes projects, while the engineering managers are responsible for meeting schedule, budget, and performance requirements. NOAO astronomers generate new instrament projects in response to user requests, scientific staff interests, and advances in technology, particularly with the development of new detectors.

As in all of NOAO, dedicated and effective individuals are responsible for the success of the program. Neil Gaughan is the engineering projects manager. The IPG reports to him, and he reports to Larry Daggert, the Manager of ETS. Neil brought a background of detailed planning for projects including low-light sensor development. The Instrament Projects Advisory Committee has scientific oversight responsibility for the program, and the task of recommending priorities for major instrament development to the NOAO Director. The committee consists of Taft Armandroff, Bob Schommer (CTIO), Todd Boroson (US Gemini Program Scientist), Dave De Young (KPNO), Jay Elias (Gemini Near-IR Spectrograph Project Scientist), Richard Elston, and Richard Green (NOAO Deputy Director and Chair). The group meets monthly with the technical managers to review schedules, resource management issues, and priorities. It conducts quarterly reviews of the program, and holds an annual open meeting to discuss plans for activities for the next fiscal year. IPAC works with Neil Gaughan and Larry Daggert to produce the detailed plan for the annual allocation of technical resources that is recommended to the Director and the NSF. It also organizes and participates in non-advocate design reviews for major projects. A system of review gates controls the rate at which resources are released to a project, subject to successful completion of the previous stage.

27 Each approved instrumentation project has a project scientist responsible for the scientific performance and a project engineer who leads the instrament technical team in meeting performance requirements, cost, and schedule. The ETS technical group itself was formally reorganized in April 1995, to merge the former IR and O/UV Groups into a single Instrament Projects Group. The two wavelength ranges demand separate dedicated engineering expertise, but the design, drafting, and fabrication resources are fully integrated. Two major new instruments were neared completion during the reporting period, and two IR instruments were in the process of upgrades to new large-format arrays.

One of the major accomplishments of the joint program was the successful testing on the telescope of the new CCD Mosaic Imaging system. The imager has a detector mosaic of eight CCDs with 2048 x 4096 format of 15 micron pixels. It has a large filter transport mechanism holding 14 six-inch filters and a pneumatically controlled shutter mechanism that gives 1% timing accuracy in 1-second exposures. Accommodation of the Mosaic Imager at the Mayall 4-m prime focus required a nearly complete rebuilding of the pedestal and focus mechanism. A new multi-element corrector with atmospheric dispersion correcting prisms was designed, polished, and integrated in the optical shop. The technical team at CTIO had to multiplex together four ARCON controllers for rapid read-out and image reassembly. An initial telescope test ran in June led to a summer of intense activity, particularly on the electronics of the controller system. The entire system was integrated successfully for a ran at the end of September, and both engineering and scientific images were collected. Remaining work is primarily in software, mostly related to user and telescope interface issues and more rapid image reassembly and display. The Mosaic Imager will be made available to KPNO users on a shared risk basis during Spring semester. At the end of the fiscal year, NOAO joined with the Carnegie Observatories for a mass buy of scientific grade CCDs, which will replace the engineering grade arrays currently being used for commissioning. The replacement should take place during calendar year 1997. Longer term plans call for production of a clone, so that the twin 4-meter telescopes can offer such an imager in each hemisphere. The capability of wide- field surveying is necessary for support of follow-up programs suitable for the Gemini telescopes.

Equally impressive progress was made on the high-resolution near-infrared spectrograph, Phoenix. Phoenix operates from 1-5 microns, using two quadrants of a new ALADDIN InSb array detector. Spectral resolution delivered by the echelle grating is designed to be 100,000 for two-pixel sampling of the slit. This instrament resides in the largest cryogenic dewar yet integrated by NOAO, and includes foreoptics to cold stop the pupil, slit and pupil viewing, dichroic beam splitting for optical guiding on the target, and a double-pass collimator-camera optical system. After first light on the telescope in June, the summer was spent tackling issues of thermal control and very low-noise performance of the ALADDIN array and new mounting. A return to the telescope in September has given confidence that the instrament is close to meeting all its performance goals. It will be available to users as a facility instrament on the 2.1-m in the spring semester.

The ALADDIN program mentioned above is a joint development effort among NOAO, the US Naval Observatory Flagstaff Station, and Hughes Santa Barbara Research Corporation. Its goal is to develop the technology for producing 1024 square InSb arrays for astronomical use. Failure modes can be benign in that arrays can have a smaller number of working quadrants which can still be useful for science. The initial investment may produce between 12 and 16

28 arrays to be shared by NOAO and USNOFS. Technical progress has been slow but steady; as of this reporting seven hybrids have been produced, and three are working in astronomical instruments.

At the same time, NOAO has been advancing its development of array controllers to handle the vastly increased number of near-IR pixels in these arrays. A hardware architecture was produced to handle the multiplexing of four quadrants read as rapidly as the array capacitance will allow, around 20 frames per second. The core of the digital system is the Datacube Digital Signal Processor, which was the basis of the DLIRIM real-time shift-and-add experiment. Several improvements have also been made in the analog front end of the controllers, with a design that supports four ADCs per card with significant noise immunity.

The two other arrays have been deployed in upgrading two existing instruments. One is COB, the Cryogenic Optical Bench. This multiple purpose imager had been used at KPNO with a 256 square InSb array to conduct the shift-and-add experiment, sampling the point spread function with 0.1" pixels. Those optics will remain in place, while the detector has been replaced by an ALADDIN array with a single working 512 square quadrant, and a suitable upgrade to the WILDFIRE controller. An initial telescope ran showed a number of minor problems to be resolved as of the end of this FY. The instrament will be shipped to CTIO in November. There it will be used with the new f/14 secondary just delivered from the Tucson optical shop. The tip/tilt capability of the secondary designed and implemented at CTIO combined with the fine angular sampling will provide an early taste of Gemini image quality to CTIO users of the Blanco Telescope.

The other instrament upgraded with an ALADDIN array is being made available through a cooperative arrangement with the Ohio State University and the Michigan-Dartmouth-MIT Observatory. OSU built their MOSAIC instrament to cover the J-K bands with cold interchangeable cameras for imaging, and slit spectroscopy with single grisms for each band. The optics were designed with large-format detectors in mind, so NOAO has provided an ALADDIN array with two (adjacent) working quadrants for the upgrade. An initial engineering ran of the TIFKAM (The Instrament Formerly Known as Mosaic) in September provided a good basis for final optimization of the system. It will be available to KPNO users on the 2.1-m and 4-m telescopes during spring semester.

Work for the Gemini Project represents the highest priority of the instrament program. NOAO won the competition to build the Gemini Near-IR Spectrograph, and began design work in FY 1996. Jay Elias is the NOAO Project Scientist and Dan Vukobratovich, formerly of University of Arizona Optical Sciences, is the Project Manager. The instrament will be the largest cryogenic device produced by NOAO, with a length of some 2 meters. It successfully passed its Conceptual Design Review in the spring. The Preliminary Design Review will be held in October. The bulk of FY 1997 will be spent bringing the design to the level of detail required for constraction and the Critical Design Review, which will be held in October 1998.

Design progress also advanced on a second-generation near-IR multi-color imager/ spectrograph. The plan calls for an instrament that can ultimately accommodate four full- format ALADDIN arrays. Since the IR opto-mechanical team is fully occupied with the Gemini spectrograph, NOAO is working in partnership with the Ohio State University for development and fabrication of this instrament. A successful conceptual design review was

29 held in May, and a Preliminary Design Review will be held in first or second quarter of FY 1997.

The Instrament Projects Group is fully committed for the activities planned for FY 1997. The first quarter will see final commissioning of the CCD Mosaic Imager, Phoenix, and the Cryogenic Optical Bench. Besides the high priority design work on the Gemini Near-Infrared Spectrograph, the Gemini Project has delegated to NOAO the responsibility for procurement of ALADDIN-type near-infrared arrays, and the production of controllers for the Gemini imager and spectrograph. The controllers effort is an upgrade of the WILDFIRE architecture to compatibility with Gemini software standards, particularly EPICS, and routine use of the Datacube DSP for image reassembly and real time shift-and-add accumulation. On the completion of the first controller system and delivery to Gemini in July 1997, a comparable system will be adapted to the upgrade of SQIID, the four-color imager, to one-quadrant ALADDIN arrays and deployment on Kitt Peak. On the optical/UV side, the joint CTIO/KPNO Users Committee recommended as their highest priority a version of the Hydra robotic multi- fiber positioner for the CTIO 4-m Blanco Telescope. That project also includes the production of a wide-field corrector with atmospheric dispersion compensation for the R-C focus. For the longer term, the optical/UV scientific group is investigating the technology for a novel approach to high-throughput optical spectroscopy. The further enrichment of the IR complement at CTIO and Gemini South leads to a plan for a clone of the Gemini IR Spectrograph that NOAO will produce for the Gemini North telescope.

V. MAJOR PROJECTS

A. Global Oscillation Network Group

The Global Oscillation Network Group (GONG) is an international, community-based project to conduct a detailed study of the internal structure and dynamics of the closest star by measuring resonating waves that penetrate throughout the solar interior. To overcome the limitations of current observations imposed by the day-night cycle at a single observatory, GONG has deployed and is now operating a six-station network of extremely sensitive and stable solar velocity mappers located around the Earth to obtain nearly continuous observations of the "five-minute" pressure oscillations. GONG has also established a distributed data reduction and analysis system to facilitate the coordinated analysis of these data. GONG data are available to any qualified investigator whose proposal has been accepted, but active membership in a GONG Scientific Team will allow early access to the data and the collaborative scientific analysis that the Teams have already initiated.

FY 1996 marked the first year of operations for the full six-site GONG network. The project has already collected more data on a wider range of oscillation modes than any preceding program. These have been provided to the Science Teams who have been aggressively analyzing them. Seven first-results papers were published by the Teams in the 31 May 1996 issue of Science magazine, and presented at various sessions at the June Meeting of the AAS in Madison.

A Scientific Advisory Committee—consisting of P. Gilman (Nat. Center for Atmospheric Research), R. Noyes (Harvard-Smithsonian Center for Astrophysics), A. Title (Lockheed- Martin Palo Alto Research Lab.), J. Toomre (U. of Colorado, Chair), and R. Ulrich (U. of

30 California, Los Angeles)—continues to provide overall scientific guidance to the Project. In addition, the Data Management and Analysis Center Users' Committee—consisting of Philip Stark (U. of California, Berkeley/Chair), Rachel Howe (Queen Mary and Westfield College), Sylvain Korzennik (Harvard-Smithsonian Center for Astrophysics), Jesper Schou (Stanford U.), and Steve Tomczyk (High Altitude Obs.)—provides important community input in the development of this critical part of the Project.

In the instrument realm, the field stations are operating at the Big Bear Solar Observatory in California, the High Altitude Observatory's site on Mauna Loa in Hawaii, the Learmonth Solar Observatory in Western Australia, the Udaipur Solar Observatory in India, the Observatorio del Teide on Tenerife in the Canary Islands, and the Cerro Tololo Inter-American Observatory in Chile.

The Project's operations group maintains daily contact with the automatically operating instruments, largely through the internet. Daily status reports and sample images are obtained from the instruments' computer systems, with e-mail or telephone contact with the host sites' support groups as required. A database of the some 200 different instrament operational parameters is being compiled for each system. Routine analyses of these data are conducted to verify performance and detect trends. Small technical teams are dispatched to roughly one site a month in a routine cycle of on-site preventative maintenance.

The technical performance of the network has been excellent, especially considering that these new systems are in their initial year of remote operation. The data duty cycle including both weather and downtime has hovered at about 90% (as high as 93%)—nominally the value predicted by the site survey. Of all the possible images that could be obtained at the individual sites, only about 0.4% have been lost to equipment difficulties, and many of these were backed up by images taken at adjacent sites.

The instrument-support arm of the operations group continues to operate the Tucson prototype station as a "ground simulator" for hardware and software enhancements that eventually propagate to the field stations. The group is also in the early stages of a feasibility study to explore the possibility of incorporating a higher resolution camera into the existing stations.

The Data Management and Analysis Center is processing the incoming data at a furious pace to keep up with the more than one gigabyte per day of data coming in from the field, and satisfy the voracious appetites of the GONG science community. These data are reduced to 36-day time series (a "GONG month") of oscillation-mode coefficients and transformed to obtain the frequency spectram for each mode and, finally, tables of mode-frequency peaks. The data from each of these and several other intermediate steps are archived as defined data products in the Data Storage and Distribution System.

The distribution of archived data to the science community is proceeding at a good rate as well. Data requests are received by e-mail, the World Wide Web, and by other forms of communication. Data distributions have exceeded five gigabytes per working day. The recent distributions have been at a rate approaching 1.5 million files per year.

The data group is continuing to provide support to the Data Scientist's in-house team and interested contributors from the community in the ongoing effort to improve understanding of the data themselves and enhance the quality of the data reduction processes. A number of such

31 enhancements have already been developed and will be incorporated into the current data pipeline and a planned reprocessing of early data to produce a more homogeneous data set as time goes on.

The Annual GONG Meeting was held in conjunction with the June AAS Meeting in Madison, Wisconsin. It was very well attended and featured a separate poster session to provide peeks at many interesting works in process. A series of Science Team meetings engaged in organization and planning for several Team science papers expanding on the first results. These papers will be sent to appropriate archival journals early in FY 1997.

Representatives from the sites participated in a separate meeting following the Annual Meeting, and we have had several-month-long scientific visitors from three of the sites participating in the development of analysis techniques in Tucson.

Observations have now established convincingly that the solar internal structure and dynamics—as measured by the p-mode frequencies that GONG utilizes—vary significantly during the solar activity cycle. Thus, the Project and the community are beginning to look seriously at the technical and scientific milestones leading up to a decision on whether to continue GONG operations beyond the baseline of three years. The exciting scientific possibilities and technical feasibility of an upgrade to a high-resolution square-pixel camera format are also being explored.

B. Precision Solar Photometric Telescope (PSPT)

The PSPT program is part of the NSF SunRISE project, which is devoted to understanding the mechanisms of solar luminosity variations. NSO began development in FY 1994 of a small network of photometric telescopes to measure solar surface brightness variations. The instruments are designed around a 15-cm objective, a 2K x 2K pixel CCD, and fast frame- selection electronics. Full-disk surface photometry with 0.1% per pixel accuracy with a one- hour cadence will be obtained.

Highlights from this year include: (1) Deployment of a prototype PSPT instrament in Rome, (2) Completion of the 2K x 2K photometric camera, and (3) Construction of the final PSPT instrument at NSO/SP.

The project is actively working to minimize development costs by seeking other scientific partners interested in the PSPT hardware. For example, the Kiepenheuer Institut fiir Sonnenphysik is currently duplicating the lKx IK prototype camera for their observatory. NSO will also share in the software development for the 2K x 2K Thomson camera system. The new camera will be useful for a broad range of high-spatial and photometric dynamic range problems, and we expect the instrument/camera costs to decrease as additional partners are identified.

C. SOLIS

Improved long-term measurements of solar activity are key to any scientific strategy for understanding the solar cycle. NSO is already the acknowledged world leader in full-disk synoptic measurements. SOLIS, proposed to NSF in February 1996 as part of the "Renewing NOAO" proposal, represents a new generation of instruments that will form the core of the US

32 synoptic capability for the next twenty years and can serve as a prototype for a worldwide synoptic network.

In order to relate measurements from GONG, RISE/PSPT, and other space- and groundbased instraments to the overall pattern of solar activity, it is necessary to make daily measurements of magnetic and velocity fields, as well as chromospheric and coronal structure, with a stable suite of well-calibrated instraments. The data provided by the SOLIS instruments will be dramatically improved in quality, quantity, and network availability compared with what is currently available. SOLIS will be cheaper to operate because of consolidation, automation, and modernization. SOLIS will replace NSO's existing synoptic facilities.

SOLIS comprises four instrament packages: a Vector Spectromagnetograph that measures the strength and direction of the magnetic field in the photosphere over the full solar disk every 15 minutes, which is of prime importance for understanding the dynamics of magnetic fields and their relation to chromospheric and coronal structure (the present spectromagnetograph only measures the net magnetic flux along the line of sight, typically once a day); a Full Disk Patrol that delivers digital full-disk images of the Sun in various spectral lines at high cadence (the present instraments typically deliver one image per day on film with a very limited selection of spectral lines); a Coronal Emission-line Imager and Photometer that provides intensity and velocity images of the corona in at least five spectral lines with high spatial resolution (the current coronal photometer performs intensity scans around the solar disk at coarse resolution once per day in three lines); and a Sun-as-a-star Precision Spectrometer that delivers very precise spectra of integrated sunlight over a substantial spectral range (current measurements are performed in a labor-intensive manner with a heterogeneous collection of older instruments using just a few spectral lines).

It is important to build and operate SOLIS soon to study the next solar maximum around the year 2000 and to support SOHO, TRACE, GONG, RISE, and other ground- and spacebased observations.

During FY 1996, NSO prepared for SOLIS by using its existing synoptic telescopes as testbeds for state-of-the-art hardware and software concepts applicable to SOLIS; by reaching out to the solar physics community through the SOLIS Web page, the NSO Users' Committee (which has strongly endorsed SOLIS), AAS/SPD meetings, and the community-based Solar Magnetism Initiative; and by pursuing the possibility of partnerships. Potential partners include the US Air Force, the NCAR High Altitude Observatory, and the NOAA Space Environment Center.

D. CLEAR Feasibility Study

Large solar telescopes are needed to answer a number of important science issues. Among these are (1) high angular resolution needed to resolve the scales at which most of the action is in solar magneto-hydrodynamics, (2) access to the infrared part of the solar spectram wanted to extend the range of physical conditions over which the solar atmosphere is studied, (3) accurate polarization observations needed to measure solar magnetic fields, (4) high sensitivities, essential to study variations in these and other solar conditions, and (5) coronagraphic capability to observe magnetic fields and small scale stractures in the solar corona. The Coronagraph and Low Emissivity Astronomical Reflector (CLEAR) is a concept which attempts to combine these qualities in one telescope.

33 This year saw major progress in the development of the CLEAR project. A technical and budgetary feasibility study of the CLEAR project has so far shown no showstoppers. This study focuses on a strawman CLEAR concept which has the following technical requirements:

Mount: alt-az, off-axis Gregorian Optics: 4 m. f/3.75 parabolic primary, f/30 Gregorian/Nasmyth/coude foci Spectral Range: 0.38 to 15 um minimal, 0.35 to 35 um optimal Image Quality: 0.1 arcsec over 5 arcmin field-of-view (FOV) FOV: 5 arcmin diameter Polarimetry: 0.01 % accuracy; 0.001 % sensitivity (photon flux allowing) Adaptive Opt: Tip-Tilt secondary mirror, adaptive optics designed for 1.6 um wavelength at 1 arcsec seeing (100 actuators). Allow in design for future growth to shorter wavelength and laser beacon use. Scatter: Coronagraphic quality

The cost model is considering various down-scoping options including relaxing the diameter and scattered light requirements. It also will include estimates of constraction and operation costs depending on site choice.

The study includes the design, modeling, analysis and costing of the telescope. Among these are modeling of the telescope structure and co-rotating telescope envelope, of the primary mirror support and thermal behavior, of the airflow in the telescope tube, and of the prime focus heatstop. Ahead of us are the constraction and testing of a 1/6 scale mock-up of the telescope enclosure to study issues related to seeing and dust control.

Parallel with the feasibility study, the CLEAR project is reviewing the suitability of existing solar observatory sites for the location of the facility. Site parameters of interest are the amount of time during which good seeing and/or coronal sky conditions are satisfied. The GONG site survey data are used as a uniform data base for sunshine hour values and extinction/sky conditions. Solar scintillometers, as seeing monitor proxies, are being installed on Hawaii, Big Bear Solar Observatory, Sac Peak, and La Palma (Canary Islands) to compare seeing conditions.

Outreach includes the CLEAR Web page (www.nso.noao.edu:80/~nsoclear/), lectures, and workshops.

VI. CENTRAL COMPUTER SERVICES

Central Computer Services consists of two groups: the IRAF (Image Reduction and Analysis Facility) group, and the Tucson computing support group.

The first bug fix patch for IRAF V2.10.4 was released early in FY 1996 for SunOS, Sun Solaris, and OSF/1. Most of the bug fixes were minor, although a serious world coordinate system bug fix was included that affected writing QPOE files in the PROS/XRAY package.

IRAF V2.10.4 for PCs ranning Linux was released at the same time (the initial release included the patch mentioned above). The IRAF V2.10.4 port to Linux was done using the Slackware 2.3 Linux distribution and the version 1.2.11 Linux kernel. The initial testing for the port was done on two

34 platforms, a high end Pentium system and a more modest 486DX2 66MHz system. The distribution includes Linux versions of xgterm and ximtool as well as an option to ran gzexe-compressed executables on those systems with limiteddiskspace.

The IRAF V2.10.4 distribution for PCs ranning Linux has been a hot item since its release. In the first several months since the release there have been roughly 275 distributions of PC-IRAF, either from the network archive or by purchase of a CD-ROM (there have been about 2500 total copies of IRAFV2.10 downloaded from our serverfor all platforms in the past couple years).

The second patch to IRAF V2.10.4 (V2.10.4-p2) was completed for the SunOS, Solaris, Linux (Slackware), and DEC Alpha OSF/1 platforms. There were some minor bug fixes as well as enhancements to support specific outside projects, but from the viewpoint of most users the main reason for its release was platform support, i.e., to support changes to operating system software or compilers. For Solaris/TRAF the patch adds support for Solaris 2.5 and the SunSoft version 4 compilers. This same distribution also supports Solaris 2.3 and 2.4. For Linux/IRAF the patch includes support for ELF-based versions of Linux, but still uses the a.out format binaries. For OSF/1, patch 2 was simply a bug fix upgrade since we are still ranning an older OSF/1 V2.0 operating system on our DEC Alpha. The current OSF1/IRAF release should ran fine under OSF/1 V3 but not the newly released Digital Unix 4.0. IRAF V2.10.4-p2 is also available now for SGLTRIX. This was essentially a new port and is a major upgrade for this platform. The port was done under IRDC 5.3. XI IIRAF binaries were also released for this platform, including support for ximtool, xgterm, and xtapemon. We would like to thank Wisconsin and the WIYN Observatory for letting us use their SGI for IRAF support.

The IRAFUsers' Committee, which met in Tucson in February (see below), made a strongplea that we upgrade our support for those platforms neglected by recent IRAF software introductions and patches. In particular we plan to make the XI IIRAF utilities (xgterm and ximtool), which have been in use for one to two years now, available on all supported platforms. A new release of XI IIRAF is due out soon and this version will be made available for all IRAF platforms. We have begun negotiations with the vendors to update our platforms in preparation for the V2.ll release. This includes updating hardware where necessary and obtaining and installing the current versions of ADC, HPUX, IRDC, Digital UNIX, and OpenVMS (and a few others). This process is already underway. Support for some older platforms will be dropped; support for Apple A/UX has already been discontinued, as our A/UX Macintosh has died. Sun 386i support was dropped previously. Unless we hear pleas from users we will probably drop support for the VAXstation running Ultrix (not to be confused with DECstation Ultrix, which is still supported, although it is slated for eventual retirement).

IRAF V2.10.4 is now available for distribution on a CDROM that includes all V2.10.4 distributions, all IRAF documentation (mostly as PostScript files), selected NOAO layered packages, and other miscellaneous items. These CDROMs are intended mainly as an alternative to tape or network distributions.

Work continues on IRAF V2.ll, currently ranning on all the IRAF development systems. V2.ll will add the FITS image kernel and the latest versions of all applications, and will upgrade all the remaining IRAF platforms not already supported by V2.10.4-p2.

We are pleased to announce that a mirror of the IRAF network archive and Web pages at the Rutherford Appleton Labs in the UK is now operational, as part of a collaborative effort with the Starlink group at RAL. The FTP archive is available via anonymous FTP to starlink-ftp.rl.ac.uk,

35 directory pub/mirrors/iraf. The URL for access to the IRAF Web pages is http://star- www.rl.ac.uk/iraf. We expect this site will be popular with UK IRAF users who have found the network connections to the US to be very slow. We are still learning how to operate a mirror efficiently; once things are ranning routinely we hope to set up additional mirrors at other locations, especially overseas.

Members of the IRAF Group attended the ADASS '95 Conference in Tucson in late October 1995, and presented various papers on current IRAF projects. The IRAF BOF held on Monday during the conference had a new format this year, emphasizing ERAF development by user sites. A number of interesting contributed talks were given, followed by a presentation on IRAF system development, and concluding with a group discussion of IRAF priorities and plans. An IRAF Developer's Workshop was held on Thursday following the conference and was attended by over 60 participants. Software developers from around the world attended the workshop to discuss their various IRAF projects. Special topics for this year included Pipeline Software, Archiving, and Data Stractures. The workshop concluded with a group discussion of future directions and priorities for IRAF development.

The IRAF User's Committee met in Tucson on 6 February to review the status of the IRAF project and to advise NOAO in setting priorities for the IRAF project during the coming year. The IRAF User's Committee is appointed by the NOAO Director to provide a communication link between NOAO and the IRAF user community. The current committee members are Jeff Pier (USNO) (Chair), Peter Eisenhardt (JPL), Andrea Prestwich (CfA, Harvard), Bill Romanishin (Oklahoma), Bill Sparks (STScI), and Steve Walton (CalState, Northridge).

A major development for the ERAF project in this fiscal year was the award of a three-year NASA ADP grant to IRAF to support the Open ERAF initiative. The Open IRAF initiative will evolve and enhance IRAF in many ways to allow better integration of IRAF with non-IRAF software and data formats, and improve the support for user software development. These enhancements will include improved facilities for host execution of IRAF tasks and scripts, multi-language support, support for host-callable IRAF libraries, and support for dynamically loadable modules. The multi-language support will give the developer a choice of any of several different programming languages including C, Fortran, and probably C++. The Open IRAF funding will also aid our efforts to develop ERAF support for distributed objects and messaging and object component technology. This project represents a collaboration of the ERAF group at NOAO and all the major ERAF development sites within NASA, including HST, AXAF, SAO, and CEA.

A major development project for IRAF will be software support for the NOAO mosaic. The NOAO Mosaic is an 8K x 8K CCD mosaic generating 128 MB (64 megapixel) images. Work thus far has concentrated on keywords and the data dictionary, the Mosaic archival FITS data format, and design of the messaging system and the real time display and mosaic viewer. The real time display and mosaic viewer will provide near real time display and quick look analysis of single frame or mosaic data during readout. The facility will be highly extensible to support integration with local instrumentation, to support various messaging systems for data capture, custom data formats, permit on the fly calibration, and so on.

Another current ERAF systems project is the transparency monitor, an automated camera that continually observes Polaris to monitor the transparency of the sky (or at least a portion of the sky). This is a high priority for KPNO and WIYN for monitoring observing conditions during photometric rans and to help manage queue observing. It is an important and interesting project for ERAF involving developing new capabilities which are important for the future evolution of ERAF,

36 such as distributed objects and messaging, support for heterogeneous systems (integrating ERAF and non-IRAF components), and other elements of the Open IRAF initiative.

Lindsey Davis has continued work on the new world coordinate driven image matching package, a first version of which was released early in FY 1996. The celestial coordinate transformations are performed using the Starlink positional astronomy library SLALEB which has recently been ported to IRAF. Lindsey has also begun work on defining the requirements for the new ERAF Astrometry package, which will be a collaborative effort of Lindsey and others in the ERAF group, working with astronomers and astrometric catalogproviders from the generalcommunity.

Rob Seaman has been busy this fiscal year with the planned expansion of the NOAO "Save the Bits" archive to include a dedicated CD-ROM based archive and data distribution system for the WEYN telescope. We are also in the process of installing Save the Bits at CTEO, working with the CTIO staff. CTIO data will be saved to dual Exabytes as is currentlydone at KPNO. Updates to the ICE CCDACQ CCD data acquisition package and to the prototypeFINDERpackage for generating plate solutions from the image display using the HST Guide Star Catalog are in various stages of completion.

Frank Valdes has been working on tools for the automated identification of arc-line spectra. The task allows various types of constraining information such as approximate central wavelength and dispersion. A minimum input to the task would be the arc line spectram, a line list, and an optional wavelength-calibrated template spectram. The new auto-identification facilities should greatly simplify the process of spectral dispersion calibration. Frank is currently extending the algorithms to multi-order echelle spectra. Other recently completed projects include improvements to the astronomical image header editor and a new astronomical calculator tool. The calculator tool may be used for many purposes, one of which is a new task that identifies, from a large set of images, a subset of images within a specified distance of a point in the sky. Frank has also enhanced the EMEXAMENE and PSFMEASURE tasks for fitting stellar profiles to include Moffat profiles. Since many groundbased stellar profiles are a better match to a Moffat profile than a Gaussian profile, the new fitting model gives better full-width at half-maximum values.

The downtown Tucson computing facilities continue to evolve as older systems are replaced by newer, more cost-effective and easier-to-maintain systems. In particular, the machines Gemini (used as a Server on the Scientist Workstation Network) and Ursa (used for data reduction and analysis by staff and visitors) were significantly upgraded during FY 1996. Also, several older disk drives on various CCS systems failed during the year and were replaced by more reliable, and also larger, disks. Similarly, older laser printers were replaced by newer, more capable printers.

The proliferation of desktop workstations, PCs and X-terminals to scientists' and engineers' offices has slowed as saturation is approached; however, many desktop systems were upgraded to faster systems over the course of the year. The network infrastructure in the downtown Tucson office building was upgraded with the addition of several special purpose networks (including a Fast Ethernet subnet) and the implementation of switched Ethernet on the building backbone network.

During FY 1996, a project was begun to completely rewrite the 14-year old Addresses, Lists and Proposals System (ALPS) used to manage observing proposals and telescope usage statistics. ALPS currently rans on a Sun system while the new version will utilize networked PCs. Enhanced functionality and maintainability is the goal of the new project.

37 VII. SCIENTIFIC STAFF

A. CTIO Scientific Staff Changes

Alejandro Clocchiatti, one of the first recipients of a Gemini Fellowship, is spending a year at CTIO carrying out supernova research.

Jack Baldwin is spending close to a year on sabbatical at the Institute of Astronomy, Cambridge, UK. Jack's sabbatical ends in December.

Jay Elias transferred to Tucson in January to take on the role of Project Scientist for the ER Spectrometer being built for Gemini by the NOAO.

Alistair Walker was promoted from Associate Astronomer with tenure to Astronomer during October.

Richard Elston was promoted from Assistant Astronomer to Associate Astronomer, also during the month of October.

Following his sabbatical here in FY 1996, Ron Probst has transferred to CTIO from KPNO for three years commencing in August. Ron will be a member of the ER program team here, with initial responsibilities for the f/14 tip tilt-system (after Richard Elston leaves) and for the cryogenic optical bench.

B. KPNO Scientific Staff Changes

Hired Date Name Position

10/1/95 Arjun Dey Research Associate 03/1/96 Michael Corbin Assistant Scientist 07/1/96 Paul Smith Assistant Scientist

Completed Employment Date Name Position

11/17/95 Stephane Chariot Research Associate 11/30/95 David Crawford Astronomer/Tenure 12/19/95 Paola Sartoretti Research Associate 12/31/95 Helmut Abt Astronomer/Tenure 12/31/95 Lloyd Wallace Astronomer/Tenure 04/15/96 Michael Corbin Assistant Scientist

38 Change ofStatus Date Name Position

10/1/95 Tod Lauer Promotion from Assistant Astronomer to Associate Astronomer 10/1/95 Philip Massey Promotion from Assistant Astronomer/Tenure to Astronomer/Tenure 02/1/96 Taft Armandroff Promotion from Associate Astronomer to Associate Astronomer/Tenure 07/1/96 David Silva Promotion from Assistant Scientist to Assistant Astronomer 08/1/96 Ronald Probst Transfer from KPNO to CTEO

C. NSO Scientific Staff Changes

Michael Dulick joined NSO/T as an NSF/Chemistry-funded Assistant Scientist, on 31 January 1996.

Rudolf Komm joined NSO/T as an SOI-funded Jr. Scientist on 15 August 1996.

John Varsik joined NSO/SP as a Research Associate on 9 October 1995.

During the reporting period, the following people visited NSO and stayed for a month or more: H.M. Antia (Tata Inst, of Fundamental Research), T. Alan Clark (U. of Calgary), Irene Gonzalez and Jesus Patron (Inst, de Astrofisica de Canarias), Jinghao Sun (Beijing Astronomical Obs.), Sushant Tripathy (Udaipur Solar Obs.), Li Yan (U. of Sydney), and Binxun Ye (Yunan Obs.).

VIII. DIRECTOR'S OFFICE

The current management stracture for NOAO consists of the following employees: Sidney Wolff, NOAO Director; Richard Green, NOAO Deputy Director; Malcolm Smith, CTIO Director/NOAO Associate Director; Mark Phillips, CTIO Assistant Director; Brace Bohannan, KPNO Assistant Director; Robert Barnes, Assistant to the KPNO Director; Jacques Beckers, NSO Director/NOAO Associate Director (Douglas Rabin served as Acting NSO Director during FY 1996); Todd Boroson, USGP Project Scientist/NOAO Associate Director; Glen Blevins, Manager, Central Administrative Services; Larry Daggert, Manager, Engineering and Technical Services; John Dunlop, Manager, Central Facilities Operations; Yvette Estok, Manager, Public Information Office; Steve Grandi, Manager, Central Computer Services.

The NOAO Director is responsible for the overall operation of NOAO, which includes providing scientific leadership for NOAO, determining priorities, planning budgets, and allocating resources. The Director represents NOAO, and in particular, the four scientific divisions (CTIO, KPNO, NSO, and USGP) to AURA, NSF and the scientific community.

39 IX. NOAO STATISTICS

A. CTIO Statistics

During the period of 1 October 1995 through 30 September 1996, a total 198 separate observing programs involving 417 scientists (223 visitors, 194 collaborators) were carried out at CTIO. In the same period, 194 papers were published based on the use of Cerro Tololo facilities. The number of nights CTIO scientific staff spent on CTIO during this period was 201. The number of public visitors to CTIO during this same period is estimated to be 5,960.

Breakdown ofCTIO Observational Statistics

The figures in the following table reflect the number of observers/users physically present at the Observatory and do not include multiple visits by a single observer/user. This table does not include NOAO staff. The total number of visits including multiple ones is 328. Visiting astronomers were assigned 93.2% of the observing time and the remaining 6.8% was assigned to the staff.

Observers/Users US Latin A. Foreign Total PhDs 105 17 37 159 Graduate Students 41 2 11 54

Technicians & Research Students 4 6 - 10 Total Visitors 150 25 48 223

Collaborators who were not physically present 134 8 52 194

Institutions represented by the above visits 63 32 102

USA Institutions (63) Lawrence Livermore Nat. Lab. Alma College Louisiana State U. Arizona State U. Maria Mitchell Obs. At&T Bell Labs. Massachusetts Inst, of Tech. Benedictine College Michigan State U. Brigham Young U. Millikin U. Caltech, IPAC NASA Ames Carnegie Inst, of Washington NASA Goddard Columbia U. NASA Johnson Cornell U. New Mexico State U. Darmouth College Ohio State U. Drew U. Pennsylvania State U. Fermi Nat. Accelerator Lab. Pomona College Franklin & Marshall College Princeton U. Georgia State U. Purdue U. Georgia Inst. Tech. Rice U. Harvard-Smithsonian Rutgers U. Imperial College, UK Saint John's College Johns Hopkins U. Space Telescope Science Inst.

40 State U. of New York Foreign Institutions (32) U. of Alabama Anglo-Australian Obs., Australia U. of Alaska Armagh Obs., Ireland U. of Arizona DAO, Canada U. of California, Berkeley Durham U., UK U. of California, Los Angeles Edinburgh U., UK U. of California, Santa Cruz European Southern Obs., Germany U. of Chicago Leicester U., UK U. of Colorado McMaster U., Canada U. of Hawaii Max-Planck Inst., Germany U. of Illinois MSSSO, Australia U. of Kansas Nagoya City U., Japan U. of Maryland Nat. Astron. Obs., Japan U. of Massachusetts Nat. Central U., Taiwan U. of Michigan Oxford U., UK U. of Minnesota SAAO, South Africa U. of Missouri Sternberg Astron. Inst., Russia U. of North Carolina Stockholm Obs., Sweden U. of Pennsylvania U. College London, UK U. of Oregon U. of Birmingham, UK U. of Texas U. of British Columbia, Canada U. of Washington U. of Cambridge, UK U. of Wisconsin U. of Central Lancashire, UK US Naval Obs. U. of Lisbon, Portugal Western Connecticut State U. U. of Montreal, Canada Yale U. U. of Sussex, UK U. of Toronto, Canada Latin American Institutions (7) U. of Victoria, Canada Las Campanas Obs., Chile U. of Wales, UK Obs. Astron. La Plata, Argentina U. of Waterloo Obs. Nacional, Brazil U. Nac. Mexico, Mexico U. de Sao Paulo, Brazil Yonsei U., Korea UFRGS, Brazil York U., Canada U. de Chile U. de La Serena, Chile

B. KPNO Statistics

During the period 1 October 1995 through 30 September 1996, a total of 254 observing programs were carried out by visitors and the NOAO staff at Kitt Peak. Associated with these programs were 492 individual scientists, and 42 programs were identified as graduate theses. Visiting astronomers were assigned 83% of the scheduled telescope time and the remaining 17% was assigned to the staff.

Astronomers using Kitt Peak telescopes in this period represented 86 US institutions and 28 foreign institutions. The top five represented are:

1) Space Telescope Science Institute (18); 2) University of Arizona (15);

41 3) Johns Hopkins University (10) and University of Colorado (10); 4) NASA Goddard Space Flight Center (8) and Pennsylvania State University (8); 5) University of Maryland (7), and Harvard-Smithsonian CfA (7).

Observers/Users US Foreign Total PhDs 243 36 279 Graduate Students 92 6 98

Technicians & Research Students 28 — 28 Total Visitors 363 42 405 Institutions represented by the above visits 86 28 114

The number of public visitors to Kitt Peak in this period is estimated to be 35,000. This estimate is based on the number of visitors attending two daily scheduled tours on Kitt Peak and does not factor in visitors taking self-guided tours or visitors scheduling special tours through the Public Information Office.

C. NSO Statistics

During the period of 1 October 1995 through 30 September 1996, a total of 211 observing programs, involving 138 individual scientific visitors and 33 staff were carried out at NSO facilities. Astronomers using NSO facilities during this period represented 42 US institutions and 25 foreign institutions. Visiting astronomers were assigned 33% of the scheduled telescope time and the remaining 67% was assigned to the staff.

During the reporting period a total of 914 outside users from 1020 institutions accessed the main NSO/Tucson data archive and distribution area a total of 11,025 times. A total of 30,425 data files were transferred during these accesses. In addition, 23 distributions per observing day are made automatically to outside users, adding approximately 5500 distributions per year for a total of over 36,000 data distributions annually to about 950 users. During this same time period, NSO web pages were accessed by outside users a total of 36,384 times. Note that these statistics are for NSO/Tucson only.

During the reporting period a total of 11608 scientific data files were transferred via anonymous ftp from NSO/Sac Peak.

Observers/Users US Foreign Total PhDs 110 35 145 Graduate Students 2 3 5 Technicians & Research Students 19 2 21 Total Visitors 98 40 138 Institutions represented by the above visits 42 25 67

D. NOAO Tucson Headquarters Building Statistics

During the period 1 October 1995 through 30 September 1996, a total of 1,777 visitors signed in at the NOAO Tucson headquarters building.

42 APPENDIX A

National Optical Astronomy Observatories October 1995 to September 1996 Technical Reports

The following papers were published by CCS personnel:

Barnes, J. (Editor) 1996, ASP Conf. 101: Astronomical Data Analysis Software and Systems V, ed. G.H. Jacoby, J. Barnes (ASP).

Bell, D.J., et al. 1996, ASP Conf. 101, ed. G.H. Jacoby (ASP), p.451, "An Automated System for Receiving KPNO Proposals by Electronic Mail"

Bell, D.J. 1996, PhD Thesis (U. of Illinois at Urbana-Champaign), "A Kinematic and Abundance Survey in the Galactic Rotational Directions"

Bragaglia, A., et al. 1996, ASP Conf. 92, ed. H. Morrison (ASP), p.175, "Definition of a Pure Sample of Nearby BHB Stars"

Cotton, S.D., Tody, D., Pence, W.D. 1995, A&AS, 113, p.159, "Binary Table Extension to FITS"

Davis, L.E. 1996, ASP Conf. 101, ed. G.H. Jacoby (ASP), p.147, "World Coordinate System Based Image Registration Tools for IRAF"

Fitzpatrick, M., Tody, D. 1996, ASP Conf. 101, ed. G.H. Jacoby (ASP), p.68, "Datastream Compression for IRAF Image Display"

Gillies, K., Walker, S. 1996, ASP Conf. 101, ed. G.H. Jacoby, p.347, "The Design of the Gemini Observatory Control System"

Heim, G.B., Buchholz, N., Fowler, A.M. 1995, SPEE, 2475, p.118, "Controlling an ALADDIN IK x IK Array with Wildfire"

Kinman, T.D., et al. 1996, AJ, 111, p.1164, "A Preliminary Discussion of the Kinematics of BHB and RR Lyrae Stars Near the North Galactic Pole"

Marshall, B., Gillies, K., Lewis, J. 1996, ASP Conf. 101, ed. G.H. Jacoby (ASP), p.408, "The Integration of Telescopes, Instruments, and User Interfaces at KPNO and WIYN"

McGehee, P.M., Wampler, S.B., Gillies, K.K. 1996, SPEE, 2479, p.193, "Command Completion Within an EPICS Database"

Mills, D. 1996, SPEE, 2479, p.50, "The WIYN Telescope Graphical User Interfaces"

Mills, D. 1996, ASP Conf. 101, ed. G.H. Jacoby (ASP), p.233, "BOF Session-Linux Users"

Seaman, R., Bohannan, B. 1996, ASP Conf. 87, ed. T.A. Boroson (ASP), p. 114, "Alternate Observing Options at Kitt Peak National Observatory"

Seaman, R. 1996, ASP Conf. 87, ed. T.A. Boroson (ASP), p.229, "Save the Bits at the Kitt Peak National Observatory" Seaman, R., Bohannan, B. 1996, ASP Conf. 101, ed. G.H. Jacoby (ASP), p.432, "Remote Observing and Automatic FTP on Kitt Peak"

Tody, D., Fitzpatrick, M. 1996, ASP Conf. 101, ed. G.H. Jacoby (ASP), p.322, "PC-ERAF: The Choice of a GNU Generation"

Valdes, F.G., et al. 1995,PASP, 107, p.1119, "FOCAS Automatic Catalog Matching Algorithms"

Valdes, F.G. 1996, ASP Conf. 101, ed. G.H. Jacoby (ASP), p.33, "Automated Arc Line Identifications in IRAF"

The following papers were published by ETS personnel:

Fowler, A.M., et al. 1995, SPIE, 2475, p.27, "ALADDEN, the 1024 x 1024 InSb Array: Test Results"

Fowler, A.M. (Editor) 1995, SPEE v.2475: Infrared Detectors and Instrumentation for Astronomy, ed. A.M. Fowler (SPIE).

Gregory, B., et al. 1995, SPEE, 2475, p.318, "Design of an Efficient Infrared Spectrometer for Large Telescopes"

Heim, G.B., Buchholz, N., Fowler, A.M. 1995, SPEE, 2475, p.118, "Controlling an ALADDIN IK x IK Array with Wildfire"

Roddier, N., et al. 1995, SPIE, 2479, p.364, "The WIYN Telescope Active Optics System" APPENDIX B

Cerro Tololo Inter-American Observatory October 1995 to September 1996 Publications List

Agostinho, R., et al. 1995, The Formation of the Milky Way, ed. E.J. Alfaro, A.J. Delgado (Cambridge U. Press), p. 211, "UVW Components, Proper Motions, Age and Chemical Composition of Disk Stars at the South Galactic Pole"

Alcock, C, et al. 1996, ApJ, 463, L67, "Real-Time Detection and Multisite Observations of Gravitational Microlensing"

Allain, S., et al. 1996, A&A, 305, p. 498, ARotational Periods and Starspot Activity of Young Solar- Type Dwarfs in the Open Cluster IC 4665"

Bailyn, CD., et al. 1995, Nature, 378, p. 157, "Dynamical Evidence for a Black Hole in the Eclipsing X- Ray Nova GRO J1655-40"

Baldwin, J., et al. 1995, ApJ, 455, LI 19, "Locally Optimally Emitting Clouds and the Origin of Quasar Emission Lines"

Baldwin, J.A., et al. 1996, ApJ, 461, p. 664, "Very High Density Clumps and Outflowing Winds in QSO Broad-Line Regions"

Baldwin, J.A., et al. 1996, ApJ, 468, LI 15 "Physical Conditions in Low- Ionization Regions of the Orion Nebula"

Balona, L.A., Krisciunas, K. 1995, ASP Conf. 83, ed. R.S. Stobie, P.A. Whitelock (ASP), p. 341, "Slowly Variable Early F-Type Stars"

Bautista, M.A., Pogge, R.W., DePoy, D.L. 1995, ApJ, 452, p. 685, "The Nebular Extinction in the Orion Nebula"

Beers, T.C., et al. 1996, AJ, 112, p. 1188, "Additonal Emission-Line Candidates From the HK Survey" Berdnikov, L.N., Turner, D.G. 1995, Astonomy Letters, 21, p. 803, "Photoelectric Observations of Southern Cepheids in 1995"

Berdnikov, L.N., Turner, D.G. 1995, Astronomy Letters, 21, p. 534, "Photoelectric UBV(RI)C Photometry of Southem-Sky Cepheids"

Bica, E., et al. 1996, ApJS, 102, p. 57, "Integrated UBV Photometry of 624 Star Clusters and Associations in the Large Magellanic Cloud"

Blum, R.D., DePoy, D.L., Sellgren, K. 1996, IAU Symp. 169, ed. L. Blitz, P. Teuben (Kluwer), p. 225, "A Comparison of Near Infrared Spectra of the Galactic Center HE I Emission Line Sources and Early Type Mass Losing Stars" Boesgaard, A.M. 1996, ASP Conf. 92, ed. H. Morrison, A. Sarajedini (ASP), p. 327, "Light Element Abundances in the Halo"

Brown, J.A., Wallerstein, G., Zucker, D. 1996, ASP Conf. 92, ed. H. Morrison, A. Sarajedini (ASP), p. 355, "Echelle Spectroscopy and Abundances in Ruprecht 106 and Pal 12"

Buta, R., Purcell, G.B., Crocker, D.A. 1995, AJ, 110, p. 1588, "Intrinsic Bar/Ring Misalignment and a Starburst Nuclear Ring in the Peculiar Spiral Galaxy ESO 565-11"

Caldwell, N., et al. 1996, AJ, 111, p. 78, "Spatial Distribution of the Starbursts in Post-Starburst Coma Cluster Galaxies"

Campusano, L., Hardy, E. 1996, IAU Symp. 173, ed. C.S. Kochanek, J.N. Hewitt (Kluwer), p. 125, "A Luminous Arc in A Z=0.042 Cluster of Galaxies, The Nearest Gravitational Arc Known?"

Carney, B.W., et al. 1995. AJ, 110, p. 1674, "The Distance to the Galactic Center Obtained by Infrared Photometry of RR Lyrae Variables"

Carswell, R.F., et al. 1996, MNRAS, 278, p. 506, "The High-Redshift Deuterium Abundance: The z = 3.086 Absorption Complex Towards Q 0420-388"

Cellone, S.A., Forte, J.C. 1996, ApJ, 461, p. 176, "Washington Photometry of Low Surface Brightness Dwarf Galaxies in the Fornax Cluster: Constraints on Their Stellar Populations"

Churchwell, E., et al. 1996, ApJ, 469, p. 209, "The Western Rim of the Vela Shell"

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Wallerstein, G. 1996, PASP, 108, p. 408, "The Spectram of Wakuda's Eraptive Star Near the Time of Outburst"

Wallin, J.F. 1995, ApJ, 453, p. 641, "AM 1354-250: Photometric Observations and Models of a Collisional Ring System"

Walter, F.M., Wolk, S.J., Neuh@user, R. 1996, Nature, 379, p. 233, "Discovery of a Nearby Isolated Neutron Star"

Wang, L., et al. 1996, ApJ, 466 p. 998, "Hubble Space Telescope Spectroscopic Observations of the Ejecta of SN 1987A at 2000 Days"

Weiner, B.J., Williams, T.B. 1996, AJ, 111, p. 1156, "Detection of H" Emission from the Magellanic Stream: Evidence for an Extended Gaseous Galactic Halo"

Williger, G.M., et al. 1996, ApJS, 104, p. 145 "Large-Scale Structure at z ~ 2.5"

Williger, G.M., et al. 1996, ASP Conf. 94, ed. P. Coles, V.J. Martinez, M.J. Pons-Borderia (ASP) p. 183, "Large-Scale Stracture at z - 2.5"

Xu, J., Crotts, A.P.S., Kunkel, W.E. 1995, ApJ, 451, p. 806, "A Three-Dimensional Study Using Light Echoes of the Stracture of the Interstellar Medium in Front of SN 1987A"

Zacharias, N„ et al. 1995, AJ, 110, p. 3093, "A Radio-Optical Reference Frame. VHE. CCD Observations from KPNO and CTIO: Internal Calibration and First Results"

Zinn, R., Bames, S. 1996, AJ, 112, p. 1054, "The Horizontal Branches of Globular Clusters. I. The Color-Magnitude Diagram of NGC 6426"

xu Publications by Telescope FY 1996

Blanco 4-m = 91 1.5-m = 45 0.9-m = 42 1-m = 14 C.Schmidt = 9 0.6-m = 8 Staff = .25 Total = 234

These figures include usage of more than one telescope per publication.

Total Publications FY 1996: 194

Xlll

APPENDIX C

Kitt Peak National Observatory October 1995 to September 1996 Publications List

Abt, H.A. 1995, ApJ, 455, p.407, "Some Statistical Highlights of the Astrophysical Journal"

Abt, H.A. 1996, ASP Conf. 90, ed. E.F. Milone (ASP), p. 15, "Keynote Address: Questions for the Present and Future"

Abt, H.A., Willmarth, D.W. 1996, ASP Conf. 90, ed. E.F. Milone (ASP), p.105, "Observational Evidence of Binary Evolution in Open Clusters"

Abt, H.A., Zhou, H. 1996, PASP, 108, p.375, "What Fraction of Astronomers Become Relatively Inactive in Research after Receiving Tenure?"

Adelman, S.J., Philip, A.G.D. 1996, ASP Conf. 92, ed. H. Morrison (ASP), p.347, "Elemental Abundances of Eight Field Horizontal-Branch A Stars"

Adelman, S.J., Philip, A.G.D. 1996, MNRAS, 280, p.285, "Elemental Abundances of Field Horizontal Branch Stars - IV. HD 74721, 86986 and 93329"

Adelman, S.J., Philip, A.G.D. 1996, Baltic Astronomy, 5, p.l 17, "Some Superficially Normal Stars with Stromgren Photometry Similar to That of Field-Horizontal-Branch Stars"

Ajhar, E.A., et al. 1996, AJ, 111, p.l 110, "Hubble Space Telescope Observations of Globular Clusters in M31. I. Color-Magnitude Diagrams, Horizontal Branch Metallicity Dependence, and the Distance to M31"

Albright, G.E., Richards, M.T. 1996, ApJ, 459, p.L99, "Doppler Tomography of Accretion Disks in Algol Binaries"

Andreon, S., et al. 1996, A&AS, 116, p.429, "Morphological Classification and Stractural Parameters for Early-Type Galaxies in the Coma Cluster"

Armandroff, T.E., Olszewski, E.W., Pryor, C. 1995, AJ, 110, p.2131, "The Mass-To-Light Ratios of the Draco and Ursa Minor Dwarf Spheroidal Galaxies. I. Radial Velocities from Multifiber Spectroscopy"

Armandroff, T.E. 1995, ASP Conf. 84, ed. J.M. Chapman (ASP), p.21, "The Use of CCDs on Schmidt Telescopes"

Baggett, S.M., MacKenty, J.W. 1996, ASP Conf. 91, ed. R. Buta (ASP), p.224, "Box/Peanut Galaxies in the Near-IR"

Bally, J., et al. 1995, ApJ, 454, p.345, "Twin Herbig-Haro Jets and Molecular Outflows in L1228"

Barden, S.C, Armandroff, T. 1995, SPEE, 2476, p.56, "The Performance of the WIYN Fiber-Fed MOS System - Hydra" Barden, S.C. 1995, SPIE, 2476, p.2, "Review of FiberOptic Properties for Astronomical Spectroscopy"

Barden, S.C, Armandroff T.E., Pryor, CP. 1996, ASP Conf. 90, ed. E.F. Milone (ASP), p.89, "The Frequency of Binary Stars Near the Tumoff in the Globular Cluster M71"

Barden, S.C. (Editor) 1995, SPEE v.2476: Fiber Optics in Astronomical Applications, ed. S.C. Barden (SPEE).

Barrado y Navascues, D., Stauffer, J.R. 1996, A&A, 310, p.879, "Lithium Abundance in Binaries of the Hyades Open Cluster"

Barrientos, L.F., Schade, D., Lopez-Craz, O. 1996, ApJ, 460, p.L89, "Luminosity Evolution in Cluster Galaxies from z=0.41 to z=0.02"

Baum, W.A., et al. 1995, AJ, 110, p.2537, "Globular Clusters in Coma Galaxy NGC 4881"

Bazan, G., Sneden, C, Yoss, K. 1996, ASP Conf. 92, ed. H. Morrison (ASP), p.351, "High Resolution Spectroscopy of Metal-Rich Halo Stars"

Beers, T.C., et al. 1996, ApJS, 103, p.433, "A Catalog of Candidate Field Horizontal-Branch and A-Type Stars. II"

Beers, T.C., et al. 1996, AJ, 112, p.l 188, "Additional Emission-Line Candidates from the HK Survey"

Bell, D.J. 1996, Ph.D. Thesis (University of Illinois at Urbana-Champaign), "A Kinematic and Abundance Survey in the Galactic Rotational Directions"

Bell, D.J., et al. 1996, ASP Conf. 101, ed. G.H. Jacoby (ASP), p.451, "An Automated System for Receiving KPNO Proposals by Electronic Mail"

Belton, M.J.S., et al. 1996, Icaras, 120, p.l, "Galileo's Encounter with 243 Ida: An Overview of the Imaging Experiment"

Belton, M.J.S., et al. 1996, Icaras, 120, p.185, "The Discovery and Orbit of 1993 (243)1 Dactyl"

Bernstein, G.M., et al. 1995, AJ, 110, p.1507, "The Luminosity Function of the Coma Cluster Core for - 25 < MR < -9.4"

Bianchi, L., Hutchings, J.B., Massey, P. 1996, AJ, 111, p.2303, "The Winds of Hot Stars in External Galaxies. III. HST UV Spectroscopy of O and B Supergiants in M31 and M33"

Blanton, E.L., et al. 1995, AJ, 110, p.2868, "Observations of the Type II-P SN 1991G in NGC 4088"

Boroson, T. 1996, ASP Conf. 87, ed. T.A. Boroson (ASP), p.13, "Queue Scheduling - One Approach Toward Evaluating Gains and Drawbacks"

Boroson, T. (Editor) 1996, ASP Conf. 87: New Observing Modes for the Next Century, ed. T. Boroson, J. Davies, I. Robson (ASP).

ii Borra, E.F., et al. 1996, AJ, 111, p.1456, "Spectroscopy of Quasar Candidates Found with Slitless Spectroscopy. II. Six Northern Fields"

Bragaglia, A., et al. 1996, ASP Conf. 92, ed. H. Morrison (ASP), p.175, "Definition of a Pure Sample of Nearby GHB Stars"

Brooke, T.Y., Sellgren, K., Smith, R.G 1996, ApJ, 459, p.209, "A Study of Absorption Features in the 3 Micron Spectra of Molecular Cloud Sources with H2 Ice Bands"

Burstein, D., Willick, J.A., Courteau, S. 1995, The Opacity of Spiral Disks, ed. J.I. Davies (Kluwer), p.73, "Inclination-Dependenceof Spiral Galaxy Physical Properties: History and Tests"

Byun, Y-L, et al. 1996, AJ, 111, p.1889, "The Centers of Early-Type Galaxies with HST. n. Empirical Models and Stractural Parameters"

Callanan, P.J., et al. 1996, ApJ, 461, p.351, "Observations of GRO J0422+32. UI. A Low-Inclination Black Hole X-Ray Nova"

Calzetti, D., et al. 1995, AJ, 110, p.2739, "An Atlas of Ha Emitting Regions in M33: A Systematic Search for SS433 Star Candidates"

Calzetti, D., Kinney, A.L., Storchi-Bergmann, T. 1996, ApJ, 458, p.132, "Dust Obscuration in Starburst Galaxies from Near-Infrared Spectroscopy"

Calzetti, D. 1996, RevMexAA, Serie de Conferencias 3, p.173, "Dust in Starburst Galaxies: Insightsfrom Near-Infrared Spectroscopy"

Campbell, J.M., et al. 1995, ApJS, 101, p.237, "InfraredAbsorption and EmissionSpectra of SiO"

Cecil, G., Morse, J.A., Veilleux, S. 1995, ApJ, 452, p.613, "Spectral Evidence for Shock-Ionized Gas Along the Jets of NGC 4258"

Chaboyer, B., Demarque, P., Sarajedini, A. 1996, ApJ, 459, p.558, "Globular Cluster Ages and the Formation of the Galactic Halo"

Chapman, C.R., et al. 1996, Icaras, 120, p.231, "Cratering on Gaspra"

Chariot, S., Worthey, G., Bressan, A. 1996, ApJ, 457, p.625, "Uncertainties in the Modeling of Old Stellar Populations"

Chariot, S. 1996, ASP Conf. 98, ed. C. Leitherer (ASP), p.275, "Comparison of Models of Young/Star- Forming Galaxies"

Ciardullo, R., Bond, H.E. 1996, AJ, 111, p.2332, "A Survey for Pulsations in O VI Nuclei of Planetary Nebulae"

Claria, J.J., Piatti, A.E., Osbom, W. 1996, PASP, 108, p.672, "DDO Metal Abundances of High- Luminosity Late-Type Stars in Galactic Open Clusters"

iii Colless, M., Dunn, A.M. 1996, ApJ, 458, p.435, "Structure and Dynamics of the Coma Cluster"

Connolly, A.J., et al. 1995, AJ, 110, p.2655, "Slicing Through Multicolor Space: Galaxy Redshifts from Broadband Photometry"

Cote, P., Fischer, P. 1996, AJ, 112, p.565, "Spectroscopic Binaries in Globular Clusters. I. A Search for Ultra-Hard Binaries on the Main Sequence in M4"

Cote, P., et al. 1996, AJ, 112, p.574, "Spectroscopic Binaries in Globular Clusters. H. A Search for Long- Period Binaries in M22"

Courteau, S., Holtzman, J. 1995, The Opacity of Spiral Disks, ed. J.I. Davies (Kluwer), p.211, "Color Gradients in Spiral Disks"

Courteau, S., de Jong, R.S., Broeils, A.H. 1996, ApJ, 457, p.L73, "Evidence for Secular Evolution in Late-Type Spirals"

Courteau, S. 1996, ApJS, 103, p.363, "Deep r-Band Photometry for Northern Spiral Galaxies"

Cowan, J.J., et al. 1996, ApJ, 460, p.L115, "First Detection of Platinum, Osmium, and Lead in a Metal- Poor Halo Star: HD 126238"

Craig, N.,et al. 1996, IAU Colloq. 152, ed. S. Bowyer (Kluwer), p.491, "The EUVE Optical Identification Campaign II: Late-Type and White Dwarf Stars"

Crawford, D.L., Craine, E. 1996, ASP Conf. 89, ed. J.R. Percy (ASP), p.183, "GNAT: A Global Network of Small Astronomical Telescopes"

Crawford, D.L. 1996, Baltic Astronomy, 5, p.247, "Philosophy of Standard Stars as Tools in Astronomical Photometry"

Crawford, D.L., Craine, E. 1996, Baltic Astronomy, 5, p.255, "A Global Network of Small Telescopes as a Resource for Photometry"

Crawford, D.L. 1996, Baltic Astronomy, 5, p.263, "Light Pollution: The Problem and the Potential Solutions"

Currie, D.G., et al. 1996, AJ, 112, p.l 115, "Astrometric Analysis of the Homunculus of t| Carinae with the Hubble Space Telescope" da Costa, L.N., et al. 1996, ApJ, 468, p.L5, "The Mass Distribution in the Nearby Universe"

Davies, M.E., et al. 1996, Icaras, 120, p.33, "The Direction of the North Pole and the Control Network of Asteroid 243 Ida"

De Young, D.S., Charles, R.D. 1995, AJ, 110, p.3107, "Numerical Simulation of Airflow Over Potential Telescope Sites"

IV De Young, D.S. 1996, ASP Conf. 100, ed. P.E. Hardee (ASP), p.261, "Boundary Layer Development, Entrainment, and Energy Transport in Radio Sources"

Dempsey, R.C, et al. 1996, AJ, 111, p.1356, "Multiwavelength Observations of Two Moderate Rotation RS CVn Systems: V815 Herculis and IM Pegasi"

Dobrzycka, D., et al. 1996, AJ, 111, p.2090, "The Hot Component of RS Ophiuchi"

Duncan, D.K., Rebull, L.M. 1996, PASP, 108, p.738, "Lithium in Young Solar-Type Stars in the Orion Nebula Region"

Dunlop, J., et al. 1996, Nature, 381, p.581, "A 3-5-Gyr-Old Galaxy at Redshift 1.55"

Durrell, P.R., et al. 1996, AJ, 112, p.972, "Globular Cluster Systems in Dwarf Elliptical Galaxies. B. The Virgo Cluster"

Dyck, H.M., et al. 1996, AJ, 111, p.1705, "Radii and Effective Temperatures for K and M Giants and Supergiants"

Elmegreen, D.M., Chromey, F.R., Johnson, CO. 1995, AJ, 110, p.2102, "Near-Infrared Observations of a Central Bar in M81"

Elmegreen, D.M., et al. 1996, AJ, 111, p.1880, "Near-Infrared Observations of Isophotal Twists in Barred Spiral Galaxies"

Elmegreen, D.M., et al. 1996, ApJ, 469, p. 131, "Star Formation in the Outer Resonance Ring of NGC 1300"

Feibelman, W.A., et al. 1995, PASP, 107, p.914, "Variability of EUE Spectra of the Pulsating Nucleus of the Planetary Nebula K 1-16"

Fekel, F,C 1996, AJ, 112, p.269, "Chromospherically Active Stars. XV. HD 8357=AR Piscium, an Extremely Active RS CVn System"

Fekel, F.C., et al. 1996, ApJ, 462, p.L95, "HDE 233517: Lithium and Excess Infrared Emission in Giant Stars"

Feldmeier, J.J., Ciardullo, R., Jacoby, G.H. 1996, ApJ, 461, p.L25, "The Planetary Nebula Distance to M101"

Fesen, R.A., et al. 1995, AJ, 110, p.2876, "Optical and Radio Emission from the Galactic Supernova Remnant HB 3 (G132.6+1.5)"

Filippenko, A.V., et al. 1995, AJ, 110, p.2261, "Was Fritz Zwicky's "Type V" SN 1961V a Genuine Supernova?"

Forbes, D. 1996, AJ, 112, p.1073, "Star Formation in NGC 6531 - Evidence from the Age Spread and Initial Mass Function" Ford, H.C, et al. 1996, ApJ, 458, p.455, "The Stellar Halo of M104. I. A Survey for Planetary Nebulae and the Planetary Nebula Luminosity Function Distance"

Fowler, A.M., et al. 1995, SPIE, 2475, p.27, "ALADDEN, the 1024 x 1024 InSb Array: Test Results"

Freedman, W.L., Madore, B.F. 1996, ASP Conf. 88, ed. V. Trimble (ASP), p.9, "The Cepheid Extragalactic Distance Scale"

Friel, E.D., et al. 1995, The Formation of the Milky Way, ed. E.J. Alfaro (Cambridge U. Press), p.189, "New Results for the Oldest Open Clusters: Kinematics and Metallicities of the Old Disk"

Fuller, G.A., et al. 1995, ApJ, 453, p.754, "The Infrared Nebula and Outflow in Lynds 483"

Gardner, J.P., et al. 1996, MNRAS, 282, p.Ll, "A Wide-Field K-Band Survey -1. Galaxy Counts in B, V, I and K"

Gebhardt, K., et al. 1996, AJ, 112, p.105, "The Centers of Early-Type Galaxies with HST. III. Non- Parametric Recovery of Stellar Luminosity Distributions"

Geisler, D, Lee, M.G., Kim, E. 1996, AJ, 111, p.1529, "Washington Photometry of the Globular Cluster System of NGC 4472.1. Analysis of the Metallicities"

Geisler, D. 1996, AJ, 111, p.480, "New Washington System CCD Standard Fields"

Geisler, D., Sarajedini, A. 1996, ASP Conf. 92, ed. H. Morrison (ASP), p.524, "Standard Giant Branches in the Washington System: Calibration and Application to the Draco, Ursa Minor and Sextans Dwarf Spheroidal Galaxies"

Gonzalez, R.A., Graham, J.R. 1996, ApJ, 460, p.651, "Tracing the Dynamics of Disk Galaxies with Optical and Infrared Surface Photometry: Color Gradients in M99"

Graham, A., et al. 1996, ApJ, 465, p.534, "Brightest Cluster Galaxy Profile Shapes"

Gregg, M.D., et al. 1996, AJ, 112, p.407, "The First Bright QSO Survey"

Griffiths, R.E., et al. 1996, Science with the Hubble Space Telescope-B, ed. P. Benvenuti (STScI), p.l 19, "Cosmology with the HST Medium Deep Survey"

Grillmair, C.J., et al. 1996, AJ, 111, p.2293, "Hubble Space Telescope Observations of Globular Clusters in M31. II. Structural Parameters"

Guo, Z., et al. 1995, ApJ, 453, p.256, "X-Ray Morphology, Kinematics, and Geometry of the Eridanus Soft X-Ray Enhancement"

Guzman, R., et al. 1996, ApJ, 460, p.L5, "On the Nature of the Faint Compact Narrow Emmision-Line Galaxies: The Half-Light Radius-Velocity Width Diagram"

Haffner, L.M., Meyer, D.M. ApJ, 453, p.450, "A Search for Interstellar C3 in the Translucent Cloud Toward HD 147889"

vi Hall, P.B., et al. 1996, ApJ, 462, p.614, "A Deep Multicolor Survey. B. Initial Spectroscopy and Comparison with Expected Quasar Number Counts"

Hall, P.B., et al. 1996, APJS, 104, p.185, "A Deep Multicolor Survey. I. Imaging Observations and Catalog of Stellar Objects"

Halpem, J.P., Helfand, D.J., Moran, E.C. 1995, ApJ, 453, p.611, "No X-Ray-Luminous Starbursts in the Einstein Medium Sensitivity Survey, Either"

Harmer, D.L., Kellett, B.J., Stickland, D.J. 1996, Observatory, 116, p.17, "The Nature of HD 220820"

Hartigan, P., Edwards, S., Ghandour, L. 1995, ApJ, 452, p.736, "Disk Accretion and Mass Loss from Young Stars"

Hartigan, P., Edwards, S., Ghandour, L. 1996, RevMexAA, Serie de Conferencias 3, p.93, "Accretion and Outflow from Young Stars"

Hartigan, P., et al. 1996, AJ, 111, p.1278, "Jet Bow Shocks and Clumpy Shells of H2 Emission in the Young Stellar Outflow Cepheus A"

Hartkopf, W.E, Mason, B.D., McAlister, H.A. 1996, AJ, 111, p.370, "Binary Star Orbits from Speckle Interferometry. VIII. Orbits of 37 Close Visual Systems"

Helfenstein, P., et al. 1996, Icarus, 120, p.48, "Galileo Photometry of Asteroid 243 Ida"

Henden, A.A. 1996, AJ, 111, p.902, "Faint Cepheid Studies. I. Comparison with Existing Data Sets"

Henry, G.W., Fekel, F.C, Hall, D.S. 1995, AJ, 110, p.2926, "An Automated Search for Variability in Chromospherically Active Stars"

Hester, J.J., et al. 1996, AJ, 111, p.2349, "Hubble Space Telescope WFPC2 Imaging of M16: Photoevaporation and Emerging Young Stellar Objects"

Hill, G.J., Goodrich, R.W., DePoy, D.L. 1996, ApJ, 462, p.163, "Observations of Paschena in a Complete Sample of Radio Galaxies"

Hill, R.S., et al. 1996, AJ, 112, p.601, "UJT: New Ultraviolet Stellar Photometry and Surface Brightness Profiles of the Globular Cluster M79 (NGC 1904)"

Hinkle, K., Wallace, L., Livingston, W. 1995, PASP, 107, p.1042, "Infrared Atlas of the Arcturas Spectrum, 0.9-5.3 Microns"

Hinkle, K.H., Bambaum, C 1996, AJ, 111, p.913, "Infrared Velocities of Long-Period Variables: The Carbon Mira S Cep"

Hinkle, K.H., Pollard, K.R., Wahlgren, G.M. 1996, ASP Conf. 92, ed. H. Morrison (ASP), p.204, "Infrared Spectroscopy of the RV Tauri Star R Scuti"

vn Hollis, J.M., et al. 1996, ApJ, 456, p.644, "The Abell 35 Nebula Inside Out"

Homer, S. 1996, ApJ, 460, p.449, "A Search for Pulsations in Four Late-Type Giants"

Howell, S.B. 1995, Ph.D. Thesis (Universiteit van Amsterdam), "Photometric Observations of Faint Cataclysmic Variables"

Hu, X. 1996, RevMexAA, Serie de Conferencias 3, p.245, "Herbig-Haro Objects in the Orion Nebula"

Hunter, D.A., et al. 1996, ApJ, 456, p.174, "The Intermediate Stellar Mass Population in NGC 604 Determined from Hubble Space Telescope Images"

Hunter, D.A., et al. 1996, ApJ, 459, p.L27, "The Intermediate-Mass Population in the Core of the R136 Star Cluster"

Hunter, D.A., et al. 1996, ApJ, 468, p.633, "The Intermediate Stellar Mass Population in the M31 OB Association NGC 206"

Etoh, Y., Tamura, M, Gatley, 1. 1996, ApJ, 465, p.L129, "A Near-Infrared Survey of the Taurus Molecular Cloud: Near-Infrared Luminosity Function"

Jacoby, G.H., Ciardullo, R., Harris, W.E. 1996, ApJ, 462, p.l, "Planetary Nebulae as Standard Candles. X. Tests in the Coma I Region"

Jacoby, G.H., Pierce, M.J. 1996, AJ, 112, p.723, "Response to Schaefer's Comments on Pierce & Jacoby (1995) Regarding the Type IA Supernova 1937C"

Jacoby, G.H. 1996, ASP Conf. 101, ed. G.H. Jacoby (ASP), p.3, "Software Demands Imposed by H[0] Studies"

Jacoby, G.H. (Editor) 1996, ASP Conf. 101: Astronomical Data Analysis Software and Systems V, ed. G.H. Jacoby, J. Bames (ASP).

Jacoby, S.H. 1996, ASP Conf. 89, ed. J.R. Percy (ASP), p.225, "NOAO K-12 Educational Outreach Activities"

Janes, K. 1996, J. Geophys. Res., 101E, p.14,853, "Star Clusters: Optimal Targets for a Photometric Planetary Search Program"

Jannuzi, B.T., et al. 1995, ApJ, 454, p.Llll, "Detection of Extended Polarized Ultraviolet Radiation from the z=1.82 Radio Galaxy 3C 256"

Jannuzi, B.T. 1996, Science with the Hubble Space Telescope-H, ed. P. Benvenuti (STScI), p.69, "Quasar Absorption Lines and the Intergalactic Medium"

Kaluzny, J., Rucinski, S.M. 1995, A&AS, 114, p.l, "CCD Photometry of Distant Open Clusters. B. NGC 6791"

Vlll Kaluzny, J., Krzeminski, W., Mazur, B. 1995, The Formation of the Milky Way, ed. E.J. Alfaro (Cambridge U. Press), p. 185, "Open Clusters as Tracers of the Evolution of the Galaxy"

Kastner, J.H., et al. 1996, ApJ, 462, p.777, "H2 Emission from Planetary Nebulae: Signpost of Bipolar Stracture"

Kaufman, M., et al. 1996, AJ, 112, p.1021, "The Arc and Other Stractures in the Center of M81"

Keel, W.C, White, HI. R.E. 1995, The Opacity of Spiral Disks, ed. J.I. Davies (Kluwer), p.167, "Properties of Dust in Backlit Galaxies"

Keel, W.C. 1996, AJ, 111, p.696, "Seyfert Galaxies with Companions: Orbital and Kinematic Clues to AGN Triggering"

Keel, W.C, Byrd, G.G. 1996, ASP Conf. 91, ed. R. Buta (ASP), p.360, "A K-Band Search for Induced Bars in Interacting Systems"

Keel, W.C, Owen, F.N., Eilek, J.A. 1996, ASP Conf. 100, ed. P.E. Hardee (ASP), p.209, "Large-Scale Motions in the Hot ISM of M 87"

Keel, W.C. 1996, APJS, 106, p.27, "Rotation Curves and Velocity Measures for Spiral Galaxies in Pairs"

Keller, L.D., et al. 1996, RevMexAA, Serie de Conferencias 3, p.251, "Ha and [FE B] 1.6435 urn Luminosities of IC 443: A Standard Candle for Counting SNR in M82"

Kenney, J.D.P., et al. 1996, AJ, 111, p.152, "Evidence for a Merger in the Peculiar Virgo Cluster Sa Galaxy NGC 4424"

Kennicutt, Jr., R.C, Gamett, D.R. 1996, ApJ, 456, p.504, "The Composition Gradient in M101 Revisited. I. H II Region Spectra and Excitation Properties"

Kenyon, S.J., Hartmann, L. 1995, ApJS, 101, p.l 17, "Pre-Main-Sequence Evolution in the Taurus-Auriga Molecular Cloud"

Kim, E., Lee, M.G., Geisler, D. 1996, IAU Symp. 174, ed. P. Hut (Kluwer), p.391, "Spatial Stracture of the Globular Cluster System Around NGC 4472"

Kinman, T.D., Allen, C. 1996, ASP Conf. 92, ed. H. Morrison (ASP), p.36, "The Horizontal Branch Morphology of Halo Field Stars"

Kinney, A.L., et al. 1996, ApJ, 467, p.38, "Template Ultraviolet to Near-Infrared Spectra of Star-Forming Galaxies and Their Application to K-Corrections"

Kochanski, G.P., Tyson, J.A., Fischer, P. 1996, AJ, 111, p.1444, "Flickering Faint Galaxies: Few and Far Between"

Kormendy, J., et al. 1996, ApJ, 459, p.L57, "Hubble Space Telescope Spectroscopic Evidence for a 2 x 109 Msun Black Hole in NGC 3115"

ix Kormendy, J., et al. 1996, IAU Symp. 171, ed. R. Bender (Kluwer), p.105, "An HST Survey of Cores of Early-Type Galaxies"

Kovo, O., Beck, S.C, Wolk, S.J. 1996, AJ, 111, p.168, "The Interacting System Arp 30"

Kulkami, V.P., et al. 1996, MNRAS, 279, p.197, "Pruning the Lymana Forest of Q1331+170"

Kwok, S., Hrivnak, B.J., Geballe, T.R. 1995, ApJ, 454, p.394, "Four Newly Identified Sources with 21 Micron Emission"

Lada, C.J., Alves, J., Lada, E.A. 1996, AJ, 111, p.1964, "Near-Infrared Imaging of Embedded Clusters: NGC 1333"

Latham, D.W., Milone, A.A.E. 1996, ASP Conf. 90, ed. E.F. Milone (ASP), p.385, "Spectroscopic Binaries Among the M67 Blue Stragglers"

Lauer, T.R., et al. 1995, AJ, 110, p.2622, "The Centers of Early-Type Galaxies with HST. I. An Observational Survey"

Lawrence, C.R., et al. 1995, AJ, 110, p.2570, "MG 0414+0534: A Dusty Gravitational Lens"

Layden, A.C. 1995, AJ, 110, p.2288, "The Metallicities and Kinematics of RR Lyrae Variables. B. Galactic Stracture and Formation from Local Stars"

Layden, A.C. 1995, AJ, 110, p.2312, "The Metallicities and Kinematics of RR Lyrae Variables. BI. On the Production of Metal-Rich RR Lyrae Stars"

Layden, A.C. 1996, ASP Conf. 92, ed. H. Morrison (ASP), p.141, "Kinematics of RR Lyrae Stars in the Inner and High Halos"

Lee, M.G., Kim, E., Geisler, D. 1996, IAU Symp. 174, ed. P. Hut (Kluwer), p.393, "Metallicity and Luminosity Functions of the Globular Clusters in NGC 4472"

Lee, P., et al. 1996, Icaras, 120, p.87, "Ejecta Blocks on 243 Ida and on Other Asteroids"

Lehnert, M.D., Heckman, T.M. 1996, ApJ, 462, p.651, "Ionized Gas in the Halos of Edge-On Starburst Galaxies: Evidence for Supernova-Driven Superwinds"

Lellouch, E., et al. 1996, ApJ, 459, p.L107, "Detection of Sulfur Monoxide in Io's Atmosphere"

Leonardi, A.J., Rose, J.A. 1996, AJ, 111, p.182, "The Ages of Starbursts in Post-Starburst Galaxies"

Liu, C.T., Green, R.F. 1996, ApJ, 458, p.L63, "Spectrophotometry and Stellar Population Models of "E + A" Galaxies"

Lowenthal, J.D., et al. 1995, ApJ, 451, p.484, "Imaging and Spectroscopy of Damped Lya Quasi-Stellar Object Absorption-Line Clouds" Luck, R.E., Wepfer, G.G. 1995, AJ, 110, p.2425, "Chemical Abundancesfor F and G Luminosity Class B Stars"

Luck, R.E., Challener, S.L. 1995, AJ, 110, p.2968, "Chemical Abundances for Very Strong-Lined Giants"

Majewski, S.R., Munn, J.A., Hawley, S.L. 1996, ApJ, 459, p.L73, "Absolute Proper Motions to B ~ 22.5: Large-Scale Streaming Motions and the Stracture and Origin of the Galactic Halo"

Majewski, S.R., Hawley, S.L., Munn, J.A. 1996, ASP Conf. 92, ed. H. Morrison (ASP), p.l 19, "Moving Groups, Stellar Streams and Phase Space Substructure in the Galactic Halo"

Martin, CL. 1996, ApJ, 465, p.680, "Kinematic Evidence for Superbubbles in I Zw 18: Constraints on the Star Formation History and Chemical Evolution"

Marziani, P., et al. 1996, ApJS, 104, p.37, "Comparative Analysis of the High- and Low-Ionization Lines in the Broad-Line Region of Active Galactic Nuclei"

Mason, B.D., et al. 1996, ASP Conf. 90, ed. E.F. Milone (ASP), p.40, "Binaries in Clusters and the Field: First Results of a Speckle Survey of O Stars"

Mason, B.D., McAlister, H.A., Hartkopf, W.I. 1996, AJ, 112, p.276, "Binary Star Orbits from Speckle Interferometry. IX. The Nearby Solar-Type Speckle-Spectroscopic Binary Fin 347 Aa"

Massey, P., Johnson, K.E., DeGioia-Eastwood, K. 1995, ApJ, 454, p.151, "The Initial Mass Function and Massive Star Evolution in the OB Associations of the Northern Milky Way"

Massey, P., et al. 1995, AJ, 110, p.2715, "Hot, Luminous Stars in Selected Regions of NGC 6822, M31, and M33"

McAlister, H.A., et al. 1996, AJ, 112, p.l 169, "ICCD Speckle Observations of Binary Stars. XEV. A Brief Survey for Duplicity Among White Dwarf Stars"

McNamara, B.R., et al. 1996, ApJ, 466, p.L9, "Optical Stracture in the Abell 1795 Cluster Central Galaxy: Evidence for Stripping and Deflection of Radio Jets"

McNamara, B.R., O'Connell, R.W., Sarazin, CL. 1996, AJ, 112, p.91, "Optical, Radio, and X-Ray Structure in NGC 1275"

McNamara, B.R., et al. 1996, ApJ, 469, p.66, "U-Band Polarimetry of the Radio-Aligned Optical Continuum in the Abell 1795 Cluster Central Galaxy"

Merrill, K.M. 1996, ASP Conf. 101, ed. G.H. Jacoby (ASP), p.416, "Quicklook IRAF Scripts for Data Acquisition Management"

Meyer, M.R. 1996, Ph.D. Thesis (University of Massachusetts Amherst), "Stellar Populations in Deeply Embedded Young Clusters: Near-Infrared Spectroscopy and Emergent Mass Distributions"

XI Miller, B.W., Rubin, V.C. 1995, AJ, 110, p.2692, "Near-Nuclear Velocities in NGC 5907: Observations and Mass Models"

Miller, B.W., Hodge, P. 1996, ApJ, 458, p.467, "Spectroscopy of H B Regions in M81 Group Dwarf Galaxies"

Moody, J.W., et al. 1995, AJ, 110, p.2088, "Evidence for Mass Outflow from the Nucleus of M101: Knots, Rings, and a Geyser"

Morrison, H., et al. 1995, AEP Conf. 336, ed. S.S. Holt (AEP), p.157, "A FaintLuminous Halo That May Trace the Dark Matter Around Spiral Galaxy NGC 5907"

Mulchaey, J.S., Wilson, A.S. 1995, ApJ, 455, p.L17, "An Alignment Between Optical Continuum and Emission-Line Structures in the Circumnuclear Regions of Seyfert Galaxies"

Mulchaey, J.S., Wilson, A.S., Tsvetanov, Z. 1996, ApJS, 102, p.309, "An Emission-Line Imaging Survey of Early-Type Seyfert Galaxies. I. The Observations"

Mulchaey, J.S., Wilson, A.S., Tsvetanov, Z. 1996, ApJ, 467, p.197, "An Emission-Line Imaging Survey of Early-Type Seyfert Galaxies. II. Implications for Unified Schemes"

Oey, M.S., Massey, P. 1995, ApJ, 452, p.210, "Triggered Star Formation and the Dynamics of a Superbubble in the LMC: The OB Association LH 47/48 in DEM 152"

Ohta, K., et al. 1996,ApJ, 458, p.L57, "Discovery of a Type 2 Quasar at z = 0.9"

Olszewski, E.W., Pryor, C, Armandroff T.E. 1996, AJ, 111, p.750, "The Mass-To-Light Ratios of the Draco and Ursa Minor Dwarf Spheroidal Galaxies. B. The Binary Population and its Effect on the Measured Velocity Dispersions of Dwarf Spheroidals"

Oswalt, T.D., Smith, J.A. 1995, White Dwarfs, ed. D. Koester (Springer), p.24, "On the Luminosity Function of White Dwarfs in Wide Binaries"

Oswalt, T.D., et al. 1996, Nature, 382,p.692, "A LowerLimitof 9.5 Gyr on the Age of the Galactic Disk from the Oldest White Dwarf Stars"

Owen, F.N., Ledlow, M.J., Keel, W.C. 1996, AJ, 111, p.53, "Optical Spectroscopy of Radio Galaxies in Abell Clusters II. BL Lacs and FR I Unification"

Owen, F.N., et al. 1996, ASP Conf. 100, ed. P.E. Hardee (ASP), p.353, "Radio Galaxies and Environment"

Patel, K., Wilson, CD. 1995, ApJ, 453, p.162, "Are Galaxies Optically Thin to Their Own Lyman- Continuum Radiation? II. NGC 6822"

Perlman, E.S., et al. 1996, ApJS, 104, p.251, "The EinsteinSlew Survey Sample of BL Lacertae Objects"

Peterson, D.M., Slowik, D. 1996, IAU Symp. 169, ed. L. Blitz (Kluwer), p.703, "The Rotation Curve from A-F Supergiants"

xii Peterson, R.C, Rood, R.T., Crocker, D.A 1995, ApJ, 453, p.214, "Rotation and Oxygen Line Strengths in Blue Horizontal-Branch Stars"

Phelps, R.L., et al. 1995, The Formation of the Milky Way, ed. E.J. Alfaro (Cambridge U. Press), p.187, "Berkeley 17: The Oldest Open Cluster?"

Phelps, R.L., Janes, K.A. 1996, AJ, 111, p.1604, "The Old Open Cluster, Berkeley 66"

Philip, A.G.D., Drilling, J.S. 1996, ASP Conf. 92, ed. H. Morrison (ASP), p.179, "The Photometric Classification of Field Horizontal Branch Stars"

Philip, A.G.D. 1996, Baltic Astronomy, 5, p.425, "CCD Photometry of Globular Clusters in the Four- Color System"

Piatti, A.E., Claria, J.J., Abadi, M.G. 1995, AJ, 110, p.2813, "Chemical Evolution of the Galactic Disk: Evidence for a Gradient Perpendicular to the Galactic Plane"

Pierce, M.J., Jacoby, G.H. 1995, AJ, 110, p.2885, ""New" B and V Photometry of the "Old" Type EA Supernova SN 1937C: Implications for H0"

Pilachowski, C, et al. 1995, PASP, 107, p.983, "High-Resolution Spectrographs for Large Telescopes"

Pilachowski, C.A., Armandroff, T.E. 1996, AJ, 111, p.l 175, "The Average Oxygen Abundance in the Globular Cluster Ml3"

Pilachowski, C.A., Sneden, C, Kraft, R.P. 1996, AJ, 111, p.1689, "Sodium Abundances in Field Metal- Poor Stars"

Pilachowski, C.A., Armandroff, T.E. 1996, ASP Conf. 92, ed. H. Morrison (ASP), p.379, "The Abundance of Oxygen in Ml3"

Pilachowski, C.A., et al. 1996, AJ, 112, p.545, "Proton Capture Chains in Globular Cluster Stars. I. Evidence for Deep Mixing Based on Sodium and Magnesium Abundances in M13 Giants"

Pustilnik, S.A., et al. 1996, IAU Symp. 171, ed. R. Bender (Kluwer), p.435, "The Large Range of Dark Matter Content in Dwarf Galaxies and Its Implications"

Rand, R.J. 1996, ApJ, 462, p.712, "Diffuse Ionized Gas in Nine Edge-On Galaxies"

Regan, M.W., Vogel, S.N. 1995, ApJ, 452, p.L21, "NGC 6946: Molecular Spiral Arms Masquerading as a Bar?"

Regan, M.W., Vogel, S.N. 1996, ASP Conf. 91, ed. R. Buta (ASP), p.129, "Morphology of Dust Lanes in Bars"

Reitzel, D., Guhathakurta, P., Gould, A. 1996, IAU Symp. 171, ed. R. Bender (Kluwer), p.437, "Isolating Red Giants in M31's Outer Spheroid: The Metallicity Gradient"

xin Reitzel, D.B., Guhathakurta, P., Gould, A. 1996, ASP Conf. 92, ed. H. Morrison (ASP), p.540, "Isolating Red Giants in M31's Outer Spheroid: The Metallicity Gradient"

Rice, W., et al. 1996,AJ, 112, p.l 14, "Near-InfraredStracture of the Edge-On Spiral NGC 4565"

Richstone, D., et al. 1996, IAU Symp. 174, ed. P. Hut (Kluwer), p.53, "The Centers of Galaxies"

Roberts, Jr., L.C., et al. 1995, AJ, 110, p.2463, "A Speckle Interferometric Survey for Asteroid Duplicity"

Romanishin, W., et al. 1995, ApJ, 455, p.516, "The Galaxy Component and Nuclear Flux Measurements of NGC 5548 from Direct Imaging"

Rose, J.A. 1996, ASP Conf. 86, ed. A. Buzzoni (ASP), p.157, "The Role of Environment on the Stellar Content of Early-Type Galaxies"

Ryans, R.S.I., et al. 1996, MNRAS, 278, p.132, "A Differential Abundance Analysis of the Early-Type Halo Star PHL 346"

Saha, A., et al. 1996, AJ, 111, p.197, "Variable Stars in the Dwarf Galaxy IC 10"

Samarasinha, N.H., Mueller, B.E.A., Belton, M.J.S. 1996, Planet. Space Sci., 44, p.275, "Comments on the Rotational State and Non-Gravitational Forces of Comet 46P/Wirtanen"

Sarajedini, A., Layden, A. 1996, ASP Conf. 92, ed. H. Morrison (ASP), p.297, "Metallicities and Reddenings for Young Globular Clusters"

Sarajedini, V.L., Green, R.F., Jannuzi, B.T. 1996, ApJ, 457, p.542, "Requirements for Investigating the Connection Between Lymana Absorption Clouds and the Large-Scale Distribution of Galaxies"

Sarajedini, A. (Editor) 1996, ASP Conf. 92: Formation of the Galactic Halo, ed. H. Morrison, A. Sarajedini (ASP).

Saraniti, D.W., Petrosian, V, Lynds, R. 1996, ApJ, 458, p.57, "Gravitational Lens Models of Arcs in Abell 2218"

Sartoretti, P., Belton, M.J.S., McGrath, M.A. 1996, Icaras, 122, p.273, "S02 Distributions on Io."

Seaman, R., Bohannan, B. 1996, ASP Conf. 87, ed. T.A. Boroson (ASP), p.l 14, "Alternate Observing Options at Kitt Peak National Observatory"

Seaman, R., Bohannan, B. 1996, ASP Conf. 101, ed. G.H. Jacoby (ASP), p.432, "Remote Observing and Automatic FTP on Kitt Peak"

Schade, D., et al. 1996, ApJ, 464, p.L63, "Evolution of Cluster and Field Elliptical Galaxies at 0.2 < z < 0.6 in the CNOC Cluster Survey"

Schweizer, F. 1996, AJ, 111, p.109, "Colliding and Merging Galaxies. BI. The Dynamically Young Merger Remnant NGC 3921"

xiv Shaya, E.J., et al. 1996, AJ, 111, p.2212, "Hubble Space Telescope Planetary Camera Images of NGC 1316 (Fomax A)"

Silva, D.R., Wise, M.W. 1996, ASP Conf. 86, ed. A. Buzzoni (ASP), p.l 17, "On Constraining Elliptical Galaxy Core Dust Distributions"

Silva, D.R., Wise, M.W. 1996, ApJ, 457, p.L15, "Interpreting Central Surface Brightness and Color Profiles in Elliptical Galaxies"

Silva, D.R. 1996, Spiral Galaxies in the Near-ER, ed. D. Minniti (Springer), p.3, "When Do Near-ER Colors Help in Studying Stellar Populations"

Simonelli, D.P., et al. 1996, Icaras, 120, p.38, "Ida Lightcurves: Consistency with Galileo Shape and Photometric Models"

Simpson, C, et al. 1996, ApJ, 457, p.L19, "An Ionization Cone and Dusty Disk in Markarian 348: The Obscuring Torus Revealed?"

Smith, D.A., et al. 1996, ApJS, 104, p.217, "Starburst Galaxies. B. Imaging and Spectroscopy of a Radio- Selected Sample"

Sneden, C, et al. 1996, ApJ, 467, p.819, "The Ultra-Metal-Poor, Neutron-Capture-Rich Giant Star CS 22892-052"

Soffner, T., et al. 1996, A&A, 306, p.9, "Planetary Nebulae and HII Regions in NGC 300"

Stepanian, J.A., et al. 1996, A&A, 309, p.702, "SBS 1425+606: A Bright, High-Redshift QSO. Illuminating a Damped Lya Absorber"

Straizys, V., Crawford, D.L., Philip, A.G.D. 1996, Baltic Astronomy, 5, p.83, "The Stromvil System: An Effective Combination of Two Medium-Band Photometric Systems"

Sullivan, R., et al. 1996, Icaras, 120, p. 119, "Geology of 243 Ida"

Szomoru, A., van Gorkom, J.H., Gregg, M.D. 1996, AJ, 111, p.2141, "An H I Survey of the Bootes Void. I. The Data."

Szomoru, A., et al. 1996, AJ, 111, p.2150, "An HI Survey of the Bootes Void. II. The Analysis"

Thomas, P.C, et al. 1996, Icaras, 120, p.20, "The Shape of Ida"

Thorbum, J.A., Hobbs, L.M. 1996, AJ, 111, p.2106, "Beryllium Abundances of Six Halo Stars"

Thomley, M.D. 1996, ApJ, 469, p.L45, "Uncovering Spiral Stracture in Flocculent Galaxies"

Tolstoy, E., et al. 1995, AJ, 110, p. 1640, "Variable Stars in the Irregular Galaxy NGC 2366 (DDO 42)"

xv Tolstoy, E. 1995, Ph.D. Thesis (Rijksuniversiteit Groningen), "Modelling the Resolved Stellar Populations of Nearby Dwarf Galaxies"

Tolstoy, E. 1996, ApJ, 462, p.684, "The Resolved Stellar Population of Leo A"

Tripp, T.M., Lu, L., Savage, B.D. 1996, ApJS, 102, p.239, "High Signal-to-Noise Echelle Spectroscopy of Quasar Absorption-Line Systems in the Direction of HS 1946+7658"

Usher, P.D., Mitchell, K.J., Huang, K.-L. 1995, ApJ, 454, p.654, "Faint Blue Objects at High Galactic Latitude. VB. Spectroscopy of Narrow-Line Objects and the Morphological Selection Criterion of the US Survey"

Van de Steene, G.C, Jacoby, G.H., Pottasch, S.R. 1996, A&AS, 118, p.243, "Optical Observations of Planetary Nebula Candidates from the Northern Hemisphere"

Van de Steene, G.C, Jacoby, G.H. 1996, ASP Conf. 102, ed. R. Gredel (ASP), p.299, "Spectroscopy of New Planetary Nebulae Close to the Galactic Center" van Dokkum, P.G., Franx, M. 1996, MNRAS, 281, p.985, "The Fundamental Plane in CL 0024 at z=0.4: Implications for the Evolution of the Mass-to-Light Ratio"

Veilleux, S., Cecil, G., Bland-Hawthorn, J. 1996, Sci. Am., 274, no.2, p.98, "Colossal Galactic Explosions"

Vennes, S., Thorstensen, J.R. 1995, White Dwarfs, ed. D. Koester (Springer), p.313, "White Dwarfs in Close Binaries in the Extreme Ultraviolet Explorer All-Sky Survey"

Veverka, J., et al. 1996, Icarus, 120, p.66, "Ida and Dactyl: Spectral Reflectance and Color Variations"

Veverka, J., et al. 1996, Icaras, 120, p.200, "Dactyl: Galileo Observations of Ida's Satellite"

Vrba, F.J., et al. 1995, Ap&SS, 231, p.85, "An Optical-IR Counterpart for SGR B1900+14?"

Vrba, F.J., et al. 1996, ApJ, 468, p.225, "The Double Infrared Source Toward the Soft Gamma-Ray Repeater SGR 1900+14"

Wallace, L., Hinkle, K. 1996, ApJS, 103, p.235, "An Infrared Spectral Atlas of Arcturas for the Range 10750-11500 cm"1 (8690-9300 A)"

Wallace, L., et al. 1996, APJS, 106, p.165, "Infrared Spectral Atlases of the Sun from NOAO"

Weintraub, D.A., Kastner, J.H., Whitney, B.A. 1995, ApJ, 452, p.L141, "In Search of HL Tauri"

Weintraub, D.A., et al. 1996, ApJ, 468, p.L45, "Diffraction-Limited 3.8 Micron Imaging of Protostellar Outflow Sources"

White B, J.C, Schlegel, E.M., Honeycutt, R.K. 1996, ApJ, 456, p.777, "BT Monocerotis: Another Extraordinary Old Nova"

xvi Willick, J.A., et al. 1996, ApJ, 457, p.460, "Homogeneous Velocity-Distance Data for Peculiar Velocity Analysis. II. Calibration of Field Samples."

Willmer, C.N.A., et al. 1996, ApJS, 104, p. 199, "A Medium Survey of a Minislice at the North Galactic Pole. II. The Data"

Wise, M.W., Silva, D.R. 1996, ApJ, 461, p.155, "The Effects of Dust on Broadband Color Gradients in Elliptical Galaxies"

Wolk, S.J., Walter, F.M. 1996, AJ, 111, p.2066, "A Search for Protoplanetary Disks Around Naked T Tauri Stars"

Woolf, V.M., Tomkin, J., Lambert, D.L. 1995, ApJ, 453, p.660, "The r-Process Element Europium in Galactic Disk F and G Dwarf Stars"

Yang, H., et al. 1996, AJ, 112, p. 146, "The Violent Interstellar Medium of NGC 604"

Zacharias, N., et al. 1995, AJ, 110, p.3093, "A Radio-Optical Reference Frame. VBI. CCD Observations from KPNO and CTIO: Internal Calibration and First Results"

xvn

APPENDIX D

National Solar Observatory October 1995 to September 1996 Publications List

Altrock, R.C, Henry, T.W. 1996, Solar-Geophysical Data, Part 1, Prompt Reports 607, ed. H.E. Coffey, "Sacramento Peak Coronal Line Synoptic Maps, 1995"

Altrock, R.C, Henry, T.W. 1996, Solar-Geophysical Data, Part 1, Prompt Reports 607, ed. H. E. Coffey, "Coronal Line Emission (Sacramento Peak), 1995"

Altrock, R.C, Henry, T.W. 1996, ASP Conference 95, eds. K.S. Balasubramaniam, S.L. Keil, R.N. Smartt, (ASP), p.324, "Prediction of Coronal-Hole Solar Wind Velocities at Ulysses from NSO/SP Coronal Data"

Andretta, V., Giampapa, M.S., Jones, H.P. 1995, Irish Astronomical Journal, 22, p. 177, "Helium in the Spectram of the Sun and of Solar-Type Stars"

Aschwanden, M.J., et al. 1995, ApJ, 454, p.512, "Solar Rotation Stereoscopy in Microwaves"

Balasubramaniam, K.S., Keil, S.L. 1996, ASP Conference 95, eds. K.S. Balasubramaniam, S.L. Keil, R.N. Smartt, (ASP), p.189, "A Search for Large-Scale Photospheric Flows as Drivers of Mass Ejections"

Balasubramaniam, K.S., Keil, S.L., Smartt, R.N. eds. 1996, ASP Conference 95, 628 pp.

Balasubramaniam, K.S., Keil, S.L., Smartt, R.N. 1996, ASP Conference 95., viii-x, "Solar Drivers of Interplanetary and Terrestrial Disturbances: Preface"

Beck, J.G., Hathaway, D.H., Simon, G.W. 1996, ASP Conference 95, eds. K.S. Balasubramaniam, S.L. Keil, R.N. Smartt, (ASP), p.196, "Observing Large-Scale Solar Surface Flows with GONG: Investigation of a Key Element in Solar Activity Buildup"

Beck. J.G., Hill, F., Ulrich, R.K. 1995, ESA SP 376, Fourth SOHO Workshop, ed. J.T. Hoeksema, (ESA), Vol. 2, p.401, "A Study of the Background Solar Velocity Spectram Using GONG Data"

Benner, D.C., et al. 1995, J. Quan. Spectr. Rad. Trans., 173, p.705, "A Multispectram Nonlinear Least Squares Fitting Technique"

Berger, T.E., et al. 1995, ApJ, 454, p.531, "New Observations of Subarcsecond Photospheric Bright Points"

Bemasconi, P.N., et al. 1995, A&A, 302, p.533, "Direct Measurements of Flux Tube Inclinations in Solar Plages"

Bocchialini, K., Koutchmy, S. 1995, ESA SP 376, Fourth SOHO Workshop, ed. J.T. Hoeksema, (ESA), Vol. 2, p.499, "Chromospheric Oscillations from Simultaneous Sequences of He I 1093 and Ca B K 393.4 Spectroscopic Measurements" Bogart, R.S., et al. 1995, ESA SP 376, Fourth SOHO Workshop, ed. J.T. Hoeksema, (ESA), Vol. 2, p.147, "Plane-WaveAnalysisof Solar Acoustic-Gravity Waves: a (Slightly) New Approach"

Bogart, R.S., et al. 1995, ESA SP 376, Fourth SOHO Workshop, ed. J.T. Hoeksema, (ESA), Vol. 2, p.151, "Preliminary Results from Plane-Wave Analysis of Helioseismic Data"

Bogdan, T.J., Braun, D.C. 1995, ESA SP 376, Fourth SOHO Workshop, ed. J.T. Hoeksema, (ESA) Vol. 2, p.31, "Active Region Seismology"

Brajsa, R., et al. 1996, Solar Phys., 163, p.79, "Helium 10830 A Measurements of the Sun"

Braun, D.C. 1995, ApJ, 451, p.859, "Scattering of p-Modes by Sunspots. I. Observations"

Brynildsen, N., Kjeldseth-Moe, O., Maltby, P. 1996, ApJ, 462, p.534, "Quiet-Sun Connection Between the C iv Resonance Lines and the Photospheric Magnetic Field"

Chang, E.S., Deming, D. 1996, Solar Phys., 165, p.257, "Observation of Infrared Lines in a Prominence at 1-5 Microns"

Christensen-Dalsgaard, J., et al. 1996, Science, 272, p.1286, "The Current State of Solar Modeling"

Cliver, E.W., et al. 1995, 24th International Cosmic Ray Conference, Vol. 4 (International Union of Pure and Applied Physics), p.257, "Extreme Propagation of Solar Energetic Particles"

Coulter, R., Kuhn, J.R., Rimmele, T. 1996, Solar Phys., 163, p.7, "Using Scintillation Measurements to Achieve High Spatial Resolution in Photometric Solar Observations"

D'Silva, S. 1996, ApJ, 462, p.519, "Measuring the Solar Internal Rotation Using Time-Distance Helioseismology: I. The Forward Approach"

Dupree, A., Penn, M.J., Jones, H.P. 1996, ApJ, 467, L121, "He I 10830 A Wing Asymmetry in Polar Coronal Holes: Evidence for Radial Outflows"

Duvall, T.L. 1995, ESA SP 376, Fourth SOHO Workshop, ed. J.T. Hoeksema, (ESA), Vol. 1, p.107, "Other Groundbased Observations"

Duvall, T.L., et al. 1996, Nature, 379, p.235, "Downflows Under Sunspots Detected by Helioseismic Tomography"

Esser, R„ et al. 1995, J. Geophys. Res., 100, p.19829, "Using FeX 6374 A and Fe XEV 5303 A Spectral Line Intensities to Study the Effect of Line of Sight Integration on Coronal Temperature Inferences"

Fan, Y., Braun, D.C, Chou, D.Y. 1995, ApJ, 451, p.877, "Scattering of p-Modes by Sunspots. B. Calculations of Phase Shifts from a Phenomenological Model"

Fan, Y., Fisher, G.H. 1996,Solar Phys., 166, p.17, "Radiative Heating and the Buoyant Rise of Magnetic Flux Tubes in the Solar Interior" Fisher, G.H., et al. 1996, IAU 153, eds. Y. Uchida, T. Kosugi, H. S. Hudson, (Kluwer), "The Dynamics of Magnetic Flux Tubes in the Solar Convection Zone — a Study of Active Region Formation"

Frohlich, C, et al. 1995, Solar Phys., 162, p.101, "Virgo: Experiment for Helioseismology and Solar Irradiance Monitoring"

Giampapa, M.S., Craine, E.R., Hott, A. 1995, Icaras, 118, p.199, "Comments on the Photometric Method for the Detection of Extrasolar Planets"

Giampapa, M.S., et al. 1995, ApJ, 463, p.707, "The Coronae of Low Mass Dwarf Stars"

Giampapa, M.S., Craine, E.R. 1995, Icarus, 118, p. 199, "The Photometric Method for the Detection of Extrasolar Planets"

Giver, L.P., et al. 1996, J. Mol. Spectr., 175, p.104, "The Rovibrational Intensities of the (40°1) <- (00°0) Pentad Absorption Bands of !2C1602 Between 7284 and 7921 cm"1"

Gough, D., et al. 1996, Science, 272, p.1281, "Perspectives in Helioseismology"

Gough, D., et al. 1996, Science, 272, p.1296, "The Seismic Stracture of the Sun"

Gu, Y. 1995, Chinese Science, 46, no. 6, "The Sun Never Sets: an Introduction to the Global Oscillation Network Group"

Guelachvili, G., et al. 1996, Spectrochimica Acta, 52A, p.717, "High-Resolution Wave-Number Standards for the Infrared"

Haber, D.A., et al. 1995, Fourth SOHO Workshop, ed. J.T. Hoeksema (ESA), p.141, "Local Area Analysis of High-Degree Solar Oscillations: New Ring Fitting Procedures"

Hanaoka, Y. 1996, Solar Phys., 165, p.275, "Flares and Plasma Flow Caused by Interacting Coronal Loops"

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