The Atacama Cosmology Telescope (Act): Beam Profiles and First Sz Cluster Maps
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Analysis and Measurement of Horn Antennas for CMB Experiments
Analysis and Measurement of Horn Antennas for CMB Experiments Ian Mc Auley (M.Sc. B.Sc.) A thesis submitted for the Degree of Doctor of Philosophy Maynooth University Department of Experimental Physics, Maynooth University, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland. October 2015 Head of Department Professor J.A. Murphy Research Supervisor Professor J.A. Murphy Abstract In this thesis the author's work on the computational modelling and the experimental measurement of millimetre and sub-millimetre wave horn antennas for Cosmic Microwave Background (CMB) experiments is presented. This computational work particularly concerns the analysis of the multimode channels of the High Frequency Instrument (HFI) of the European Space Agency (ESA) Planck satellite using mode matching techniques to model their farfield beam patterns. To undertake this analysis the existing in-house software was upgraded to address issues associated with the stability of the simulations and to introduce additional functionality through the application of Single Value Decomposition in order to recover the true hybrid eigenfields for complex corrugated waveguide and horn structures. The farfield beam patterns of the two highest frequency channels of HFI (857 GHz and 545 GHz) were computed at a large number of spot frequencies across their operational bands in order to extract the broadband beams. The attributes of the multimode nature of these channels are discussed including the number of propagating modes as a function of frequency. A detailed analysis of the possible effects of manufacturing tolerances of the long corrugated triple horn structures on the farfield beam patterns of the 857 GHz horn antennas is described in the context of the higher than expected sidelobe levels detected in some of the 857 GHz channels during flight. -
Clover: Measuring Gravitational-Waves from Inflation
ClOVER: Measuring gravitational-waves from Inflation Executive Summary The existence of primordial gravitational waves in the Universe is a fundamental prediction of the inflationary cosmological paradigm, and determination of the level of this tensor contribution to primordial fluctuations is a uniquely powerful test of inflationary models. We propose an experiment called ClOVER (ClObserVER) to measure this tensor contribution via its effect on the geometric properties (the so-called B-mode) of the polarization of the Cosmic Microwave Background (CMB) down to a sensitivity limited by the foreground contamination due to lensing. In order to achieve this sensitivity ClOVER is designed with an unprecedented degree of systematic control, and will be deployed in Antarctica. The experiment will consist of three independent telescopes, operating at 90, 150 or 220 GHz respectively, and each of which consists of four separate optical assemblies feeding feedhorn arrays arrays of superconducting detectors with phase as well as intensity modulation allowing the measurement of all three Stokes parameters I, Q and U in every pixel. This project is a combination of the extensive technical expertise and experience of CMB measurements in the Cardiff Instrumentation Group (Gear) and Cavendish Astrophysics Group (Lasenby) in UK, the Rome “La Sapienza” (de Bernardis and Masi) and Milan “Bicocca” (Sironi) CMB groups in Italy, and the Paris College de France Cosmology group (Giraud-Heraud) in France. This document is based on the proposal submitted to PPARC by the UK groups (and funded with 4.6ML), integrated with additional information on the Dome-C site selected for the operations. This document has been prepared to obtain an endorsement from the INAF (Istituto Nazionale di Astrofisica) on the scientific quality of the proposed experiment to be operated in the Italian-French base of Dome-C, and to be submitted to the Commissione Scientifica Nazionale Antartica and to the French INSU and IPEV. -
Searching for the Missing Baryons in Clusters
Searching for the missing baryons in clusters Bilhuda Rasheed, Neta Bahcall1, and Paul Bode Department of Astrophysical Sciences, 4 Ivy Lane, Peyton Hall, Princeton University, Princeton, NJ 08544 Edited by Marc Davis, University of California, Berkeley, CA, and approved January 10, 2011 (received for review July 8, 2010) Observations of clusters of galaxies suggest that they contain few- fraction in the richest clusters, it is still systematically below er baryons (gas plus stars) than the cosmic baryon fraction. This the cosmic value. This baryon discrepancy, especially the gas frac- “missing baryon” puzzle is especially surprising for the most mas- tion, is observed to increase with decreasing cluster mass (14, 15). sive clusters, which are expected to be representative of the cosmic This raises the questions: Where are the missing baryons? Why matter content of the universe (baryons and dark matter). Here we are they “missing”? show that the baryons may not actually be missing from clusters, Attempted explanations for the missing baryons in clusters but rather are extended to larger radii than typically observed. The range from preheating or other energy inputs that expel gas from baryon deficiency is typically observed in the central regions of the system (16–22, and references therein), to the suggestion of clusters (∼0.5 the virial radius). However, the observed gas-density additional baryonic components not yet detected [e.g., cool gas, profile is significantly shallower than the mass-density profile, faint stars (10, 23)]. Simulations, which do suggest a depletion of implying that the gas is more extended than the mass and that cluster gas in the inner regions of clusters, do not yet contain all the gas fraction increases with radius. -
Calibration of a Polarimetric Microwave Radiometer Using a Double Directional Coupler
remote sensing Article Calibration of a Polarimetric Microwave Radiometer Using a Double Directional Coupler Luisa de la Fuente 1,* , Beatriz Aja 1 , Enrique Villa 2 and Eduardo Artal 1 1 Departamento de Ingeniería de Comunicaciones, Universidad de Cantabria, 39005 Santander, Spain; [email protected] (B.A.); [email protected] (E.A.) 2 IACTEC, Instituto de Astrofísica de Canarias, 38205 La Laguna, Spain; [email protected] * Correspondence: [email protected] Abstract: This paper presents a built-in calibration procedure of a 10-to-20 GHz polarimeter aimed at measuring the I, Q, U Stokes parameters of cosmic microwave background (CMB) radiation. A full-band square waveguide double directional coupler, mounted in the antenna-feed system, is used to inject differently polarized reference waves. A brief description of the polarimetric microwave radiometer and the system calibration injector is also reported. A fully polarimetric calibration is also possible using the designed double directional coupler, although the presented calibration method in this paper is proposed to obtain three of the four Stokes parameters with the introduced microwave receiver, since V parameter is expected to be zero for the CMB radiation. Experimental results are presented for linearly polarized input waves in order to validate the built-in calibration system. Keywords: radiometer; polarimeter calibration; microwave polarimeter; radiometer calibration; radio astronomy receiver; cosmic microwave background receiver; Stokes parameters Citation: de la Fuente, L.; Aja, B.; Villa, E.; Artal, E. Calibration of a 1. Introduction Polarimetric Microwave Radiometer Remote sensing applications employ sensitive instruments to fulfill the scientific goals Using a Double Directional Coupler. of dedicated missions or projects, either space or terrestrial. -
Proposal 2003.Tex
i TABLE OF CONTENTS SUMMARY OF PERSONNEL AND WORK EFFORT -3 1 SUMMARY 1 2 INTRODUCTION, OBJECTIVES, AND SIGNIFICANCE 2 3 TECHNICAL APPROACH 5 3.1 Introduction 5 3.2 Radiometer Design and Calibration 6 3.3 Radiometer Module — “Radiometer on a Chip” 6 3.4 Massive Array Integration 8 3.5 Optical Design 9 3.6 Orthomode Transducers 10 3.7 Data Acquisition and Bias Control Board 10 4 BOLOMETERS AND HEMTs: Comparative Assessment 11 5 IMPACT ON THE FIELD & RELATIONSHIP TO PREVIOUS AWARD 13 5.1 Impact on the Field 13 5.2 Results of Previous Work 13 6 RELEVANCE TO NASA STRATEGIC PLAN 14 7WORK PLAN 14 7.1 Overview 14 7.2 Roles of Investigators 15 7.3 Management Structure 15 7.4 Technical Challenges 15 7.5 Milestones 15 REFERENCES 16 SUMMARY OF PERSONNEL AND WORK EFFORT iii SUMMARY OF PERSONNEL AND WORK EFFORT The proposed work is one piece of a larger effort with many components, funded from several sources, as detailed in the proposal. The table below lists the fractional support for investigators requested in this proposal alone, and also the total fraction of time they are devoting to the entire larger effort. Percentages are averages over two years. See budget and text for details. TIME Name Status Institution This prop. Total T. Gaier ................... PI JPL 22% 72% C. R. Lawrence ............. CoI JPL 5% 15% M. Seiffert ................. CoI JPL 18% 45% S. Staggs .................. CoI Princeton 10% B. Winstein ................ CoI UChicago 20% E. Wollack ................. CoI GSFC 10% A. C. S. Readhead .......... CoIlaborator Caltech T. -
A Bit of History Satellites Balloons Ground-Based
Experimental Landscape ● A Bit of History ● Satellites ● Balloons ● Ground-Based Ground-Based Experiments There have been many: ABS, ACBAR, ACME, ACT, AMI, AMiBA, APEX, ATCA, BEAST, BICEP[2|3]/Keck, BIMA, CAPMAP, CAT, CBI, CLASS, COBRA, COSMOSOMAS, DASI, MAT, MUSTANG, OVRO, Penzias & Wilson, etc., PIQUE, Polatron, Polarbear, Python, QUaD, QUBIC, QUIET, QUIJOTE, Saskatoon, SP94, SPT, SuZIE, SZA, Tenerife, VSA, White Dish & more! QUAD 2017-11-17 Ganga/Experimental Landscape 2/33 Balloons There have been a number: 19 GHz Survey, Archeops, ARGO, ARCADE, BOOMERanG, EBEX, FIRS, MAX, MAXIMA, MSAM, PIPER, QMAP, Spider, TopHat, & more! BOOMERANG 2017-11-17 Ganga/Experimental Landscape 3/33 Satellites There have been 4 (or 5?): Relikt, COBE, WMAP, Planck (+IRTS!) Planck 2017-11-17 Ganga/Experimental Landscape 4/33 Rockets & Airplanes For example, COBRA, Berkeley-Nagoya Excess, U2 Anisotropy Measurements & others... It’s difficult to get integration time on these platforms, so while they are still used in the infrared, they are no longer often used for the http://aether.lbl.gov/www/projects/U2/ CMB. 2017-11-17 Ganga/Experimental Landscape 5/33 (from R. Stompor) Radek Stompor http://litebird.jp/eng/ 2017-11-17 Ganga/Experimental Landscape 6/33 Other Satellite Possibilities ● US “CMB Probe” ● CORE-like – Studying two possibilities – Discussions ongoing ● Imager with India/ISRO & others ● Spectrophotometer – Could include imager – Inputs being prepared for AND low-angular- the Decadal Process resolution spectrophotometer? https://zzz.physics.umn.edu/ipsig/ -
Wideband Digital Correlator Development for Amiba
1 Wideband Digital Correlator Development for AMiBA Chao-Te Li*, Homin Jiang, Howard Liu, Derek Kubo, Kim Guzzino and Ming-Tang Chen ionization (EoR), when the protostars were formed to re-ionize Abstract—A wideband digital correlator using high ‐ speed the HI in the early universe [4], a digital correlator is needed to analog‐to‐digital converters (ADCs) and field‐programmable gate obtain finer spectral resolutions for molecular line observations. arrays (FPGAs) was developed for the Array for Microwave Assuming CO is abundant in galaxies, the observations of CO Background Anisotropy (AMiBA). The objective is to detect lines can trace the protostars and galaxies. The results would be spectral lines for intensity mapping in cosmology. To make use of complementary to the HI observations. However, AMiBA the 16‐GHz intermediate frequency (IF) bandwidth of AMiBA, a receivers may have to observe at lower frequencies because the 5 giga sample per second (Gsps) ADC was developed. The IF signals were downconverted, digitized, and then streamed through spectral lines have been red shifted. FPGA‐based processing units for correlation. A prototype one‐ baseline correlator using 5‐Gsps ADC modules has been deployed. The correlator for a seven‐ element system is currently under development. Index Terms—AMiBA, correlator, digital signal processing (DSP), FPGA, intensity mapping I. INTRODUCTION he Array for Microwave Background Anisotropy (AMiBA) T [1] detects finite differences in the cosmic microwave background (CMB) - the thermal remnant of the Big Bang. AMiBA receivers observe in the W‐band, from 86 to 102 GHz, where the foreground contamination, such as dust emission, Fig. -
Measuring the Polarization of the Cosmic Microwave Background
Measuring the Polarization of the Cosmic Microwave Background CAPMAP and QUIET Dorothea Samtleben, Kavli Institute for Cosmological Physics, University of Chicago Outline Theory point of view Ø What can we learn from the Cosmic Microwave Background (CMB)? Ø How to characterize and describe the CMB Ø Why is the CMB polarized? Experiment point of view Ø CMB polarization experiments Ø CAPMAP experiment, first results Ø Future of CMB measurements Ø QUIET experiment, status and plans Where does the CMB come from? Ø Temperature cool enough that electrons and protons form first atoms => The universe became transparent Ø Photons from that ‘last scattering surface’ give direct snapshot of the infant universe Ø Still around today but cooled down (shifted to microwaves) due to expansion of the universe CMB observations Interstellar CN absorption lines 1941! Accidental discovery 1965 Blackbody Radiation, homogenous, isotropic DT £ (1- 3)x10-3 (Partridge & Wilkinson, 1967) WHY? T Rescue by Inflationary models Inflation increases volume of universe by 1063 in 10-30 seconds Consequences (observables) for CMB: Ø Homogenous, isotropic blackbody radiation Ø Scale-invariant temperature fluctuations Ø On small scales (within horizon) temperature fluctuations from ‘accoustic oscillations’ (radiation pressure vs gravitational attraction) Ø Polarization anisotropies, correlated with temperature anisotropies Ø Gravitational waves, produced by inflation, cause distinct pattern in CMB polarization anisotropy Ø Reionization period will impact the fluctuation pattern -
June 19, 2008 19:16 WSPC/Guidelines-MPLA 02808
June 19, 2008 19:16 WSPC/Guidelines-MPLA 02808 Modern Physics Letters A Vol. 23, Nos. 17{20 (2008) 1675{1686 c World Scientific Publishing Company AMIBA: FIRST-YEAR RESULTS FOR SUNYAEV-ZEL'DOVICH EFFECT JIUN-HUEI PROTY WU, TZI-HONG CHIUEH, CHI-WEI HUANG, YAO-WEI LIAO, FU-CHENG WANG Physics Department, National Taiwan University No.1 Sec.4, Roosevelt Road, Taipei 106, Taiwan [email protected] PABLO ALTIMIRANO, CHA-HAO CHANG, SU-HAO CHANG, SU-WEI CHANG, MING-TANG CHEN, GUILLAUME CHEREAU, CHIH-CHIANG HAN, PAUL T. P. HO, YAO-DE HUANG, YUH-JING HWANG, HOMIN JIANG, PATRICK KOCH, DEREK KUBO, CHAO-TE LI, KAI-YANG LIN, GUO-CHIN LIU, PIERRE MARTIN-COCHER, SANDOR MOLNAR, HIROAKI NISHIOKA, PHILIPPE RAFFIN, KEIICHI UMETSU Academia Sinica, Institute of Astronomy and Astrophysics, P.O.Box 23-141, Taipei 106, Taiwan MICHAEL KESTEVEN, WARWICK WILSON Australia Telescope National Facility, P.O.Box 76, Epping NSW 1710, Australia MARK BIRKINSHAW, KATY LANCASTER University of Bristol, Tyndall Avenue, Bristol BS6 5BX, U.K. We discuss the observation, analysis, and results of the first-year science operation of AMiBA, an interferometric experiment designed to study cosmology via the measure- ment of Cosmic Microwave Background (CMB). In 2007, we successfully observed 6 galaxy clusters (z < 0:33) through the Sunyaev-Zel'dovich effect. AMiBA is the first CMB interferometer operating at 86{102 GHz, currently with 7 close-packed antennas of 60 cm in diameter giving a synthesized resolution of around 6 arcminutes. An observ- ing strategy with on-off-source modulation is used to remove the effects from electronic offset and ground pickup. -
Downloaded E E E From
APJS, 191:423–438,2010 DECEMBER Preprint typeset using LATEX style emulateapj v. 11/10/09 THE ATACAMA COSMOLOGY TELESCOPE (ACT): BEAM PROFILES AND FIRST SZ CLUSTER MAPS A. D. HINCKS1, V. ACQUAVIVA2,3 ,P.A.R.ADE4 , P. AGUIRRE5,M.AMIRI6,J.W.APPEL1,L.F.BARRIENTOS5,E.S.BATTISTELLI7,6, J. R.BOND8 ,B.BROWN9,B.BURGER6,J.CHERVENAK10,S.DAS11,1,3 ,M.J.DEVLIN12,S.R.DICKER12,W.B.DORIESE13, J. DUNKLEY14,1,3 ,R.DÜNNER5, T. ESSINGER-HILEMAN1,R.P.FISHER1,J.W.FOWLER1,A.HAJIAN8,3,1 ,M.HALPERN6, M. HASSELFIELD6,C.HERNÁNDEZ-MONTEAGUDO15,G.C.HILTON13,M.HILTON16,17 ,R.HLOZEK14,K.M.HUFFENBERGER18, D. H. HUGHES19,J.P.HUGHES2,L.INFANTE5,K.D.IRWIN13,R.JIMENEZ20,J.B.JUIN5 ,M.KAUL12,J.KLEIN12,A.KOSOWSKY9, J. M. LAU21,22,1 ,M.LIMON23,12,1 , Y.-T. LIN24,3,5 ,R.H.LUPTON3, T. A. MARRIAGE25,3 ,D.MARSDEN12 ,K.MARTOCCI26,1 , P. MAUSKOPF4, F. MENANTEAU2,K.MOODLEY16,17 ,H.MOSELEY10,C.B.NETTERFIELD27,M.D.NIEMACK13,1,M.R.NOLTA8,L.A.PAGE1, L. PARKER1,B.PARTRIDGE28,H.QUINTANA5,B.REID20,1 ,N.SEHGAL21,J.SIEVERS8,D.N.SPERGEL3, S.T.STAGGS1,O.STRYZAK1, D.S. SWETZ12,13,E.R.SWITZER26,1,R.THORNTON12,29 ,H.TRAC30,3 ,C.TUCKER4,L.VERDE20,R.WARNE16,G.WILSON31, E. WOLLACK10, AND Y. ZHAO1 1 Joseph Henry Laboratories of Physics, Jadwin Hall, Princeton University, Princeton, NJ 08544, USA 2 Department of Physics and Astronomy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854-8019, USA 3 Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544, USA 4 School of Physics and Astronomy, Cardiff University, The Parade, Cardiff, Wales CF24 3AA, -
European Cosmic Microwave Background Studies: Context and Roadmap
European Cosmic Microwave Background Studies: Context and Roadmap A list of contributors can be found in the appendix. September 17, 2018 Contents 1 Introductory Summary 1 2 Science 1 3 Experimental Landscape 2 4 Proposed Roadmap 5 1 Introductory Summary Figure 1: Constraints on parameters of the base-ΛCDM The Cosmic Microwave Background has been one of the model from the separate Planck EE, TE, and TT high- primary drivers behind the advent of so-called precision l spectra combined with low-` polarization (lowE), and, cosmology. Europe in general, and the Planck Satellite in the case of EE also with BAO, compared to the joint in particular, has recently played a large role in the field. result using Planck TT,TE,EE+lowE. Parameters on the But as with any endeavor, planning and investment must bottom axis are sampled MCMC parameters with flat pri- be maintained in order to ensure that the European CMB ors, and parameters on the left axis are derived parameters −1 −1 community continues to thrive. The European CMB Co- (with H0 in km s Mpc ). Contours contain 68 % and ordinators have taken it upon themselves to proselytize for 95 % of the probability. From Planck Collaboration et al. such planning. With this Florence Process, we attempt to (2018) inventory the community's priorities and to clearly present them in order to help with resource prioritization. There are at least three broad CMB science axes, which 2 Science here we'll call the Primordial Universe, Large-Scale Struc- ture, and Spectroscopy. While we can do all these different While a satellite such as Planck, with an approximately things with the CMB, to do each well does take some spe- 1.7 m mirror and an orbit at the second Sun-Earth La- cialization and differentiation. -
How Accurately Can the SZ Effect Measure Peculiar Cluster Velocities
A&A 374, 1–12 (2001) Astronomy DOI: 10.1051/0004-6361:20010659 & c ESO 2001 Astrophysics How accurately can the SZ effect measure peculiar cluster velocities and bulk flows? N. Aghanim1,K.M.G´orski2,3, and J.-L. Puget1 1 IAS-CNRS, Bˆatiment 121, Universit´e Paris Sud, 91405 Orsay Cedex, France 2 ESO, Karl-Schwarzschild-Str. 2, 85748 Garching bei M¨unchen, Germany 3 Warsaw University Observatory, Poland Received 30 January 2001 / Accepted 4 May 2001 Abstract. The Sunyaev-Zel’dovich effect is a powerful tool for cosmology that can be used to measure the radial peculiar velocities of galaxy clusters, and thus to test, and constrain theories of structure formation and evolution. This requires, in principle, an accurate measurement of the effect, a good separation between the Sunyaev- Zel’dovich components, and a good understanding of the sources contributing to the signal and their effect on the measured velocity. In this study, we evaluate the error in the individual radial peculiar velocities determined with Sunyaev-Zel’dovich measurements. We estimate, for three cosmological models, the errors induced by the major contributing signals (primary Cosmic Microwave Background anisotropies, Sunyaev-Zel’dovich effect due to the background cluster population, residuals from component separation and instrumental noise). We generalise our results to estimate the error in the bulk velocity on large scales. In this context, we investigate the limitation due to the Sunyaev-Zel’dovich source (or spatial) confusion in a Planck-like instrumental configuration. Finally, we propose a strategy based on the future all-sky Sunyaev-Zel’dovich survey, that will be provided by the Planck mission, to measure accurately the bulk velocities on large scales up to redshift 1, or more.