List of cosmic microwave background experiments

A comparison of the sensitivity and resolution of WMAP with COBE and Penzias and Wilson's telescope, simulated data[1]

This list is a compilation of experiments measuring the cosmic microwave background (CMB) radiation anisotropies and polarization since the first detection of the CMB by Penzias and Wilson in 1964. There have been a variety of experiments to measure the CMB anisotropies and polarization since its first observation in 1964 by Penzias and Wilson. These include a mix of ground-, balloon- and space-based receivers.[2][3] Some notable experiments in the list are COBE, which first detected the temperature anisotropies of the CMB, and showed that it had a black body spectrum; DASI, which first detected the polarization signal from the CMB;[4] CBI, which made high-resolution observations and obtained the first E-mode polarization spectrum; WMAP; and the Planck spacecraft, which has produced the highest resolution all-sky map to-date of both the temperature anisotropies and polarization signals.[5] Current scientific goals for CMB observation include precise measurement of gravitational lensing, which can constrain the mass of the neutrino; and measurement of B-mode polarization as possible evidence for cosmic inflation.

The design of cosmic microwave background experiments[2][3][4][6][7] is a very challenging task. The greatest problems are the receivers, the telescope optics and the atmosphere. Many improved microwave amplifier technologies have been designed for microwave background applications. Some technologies used are HEMT, MMIC, SIS and bolometers.[7] Experiments generally use elaborate cryogenic systems to keep the amplifiers cool. Often, experiments are interferometers which only measure the spatial fluctuations in signals on the sky, and are insensitive to the average 2.7 K background.[4]

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Another problem is the 1/f noise intrinsic to all detectors. Usually the experimental scan strategy is designed to minimize the effect of such noise.[6] To minimize side lobes, microwave optics usually utilize elaborate lenses and feed horns. Finally, in ground-based (and, to an extent, balloon-based) instruments, water and oxygen in the atmosphere emit and absorb microwave radiation. Even at frequencies where the atmospheric transmission is high, atmospheric emission contributes photon noise that limits the sensitivity of an experiment. CMB research therefore uses of air- and space-borne experiments, as well as dry, high altitude locations such as the Chilean Andes and the South Pole.[8]

Cosmic microwave background experiments

This list is incomplete; you can help by expanding it.

The list below consists of a partial list of past, current and planned CMB experiments. The name, start and end years of each experiment are given, followed by the basis of the experiment—whether space, balloon or ground based—and the location where appropriate. The frequency and amplifier technologies used are given, as is the main targets of the experiments.[9]

Image Name Start End Basis Location Frequency (GHz) Detector technology Targets References
Advanced Cosmic Microwave Explorer (ACME)
Also HACME: HEMT+ACME
1988 1996 Ground 26–35; 38–45 HEMT Temperature anisotropies [9]
Antarctic Plateau Anisotropy Chasing Experiment (APACHE) 1995 1996 Ground Antarctic 100, 150, 250 Bolometer Temperature anisotropies [9]
Absolute Radiometer for Cosmology, Astrophysics, and Diffuse Emission (ARCADE) 2001 2006 Balloon 3, 5, 7, 10, 30, 90 HEMT CMB Spectrum [9]
Archeops 1999 2002 Balloon 143, 217, 353, 545 Bolometer Measured large and intermediate scale with improved precision at the larger scales. [9]
Arcminute Cosmology Bolometer Array Receiver (ACBAR) 2001 2008 Ground South Pole 150, 219, 274 Bolometer Temperature anisotropies [9]
Arcminute Microkelvin Imager (AMI) 2005 Ground UK: Mullard Radio Astronomy Observatory 12-18 Interferometer SZ effect, Temperature anisotropies [9]
Q U I JOint TEnerife (QUIJOTE) 2012 Ground Tenerife 11, 13, 17, 19, 30, 40 Polarizer / OMT Polarization on degree angular scales [9]
ARGO 1988, 1990, 1993 1993 Balloon 150-600 Bolometer [9]
Array for Microwave Background Anisotropy (AMiBA) 2007 Ground Hawaii: Mauna Loa 86-102 Interferometer/MMIC SZ effect; Polarization [9][10][11]
Atacama B-Mode Search (ABS) 2012 Ground Chile: Atacama Desert 145 Bolometer Polarization [9][12]
Atacama Cosmology Telescope (ACT) 2008 Ground Chile: Atacama Desert 148, 218, 277 Bolometer Temperature anisotropies [9]
Atacama Pathfinder Experiment (APEX) 2007 Ground Chile: Atacama Desert 150, 217 Bolometer Temperature anisotropies; SZ effect [9]
Australia Telescope Compact Array (ATCA) 1991 1997 Ground Paul Wild Observatory, New South Wales, Australia 8.7 HEMT [9]
Background Emission Anisotropy Scanning Telescope (BEAST) 2000 Balloon, Ground 25-35; 38-45 HEMT A ground single dish CMB observatory at the University of California's White Mountain Peak Research station. [9]
Background Imaging of Cosmic Extragalactic Polarization (BICEP1) 2006 2008 Ground South Pole 100, 150, 220 Bolometer Measured degree-scale polarization with improved precision. [9][13]
BICEP2 2009 2012 Ground South Pole 150 Bolometer Degree-scale B-mode polarization. [9][14]
Keck Array 2010 Ground South Pole 95, 150, 220 Bolometer Degree-scale B-mode polarization. [9]
Balloon-borne Anisotropy Measurement (BAM) 1995 1998 Balloon University of British Columbia and Brown University balloon experiment 110-250 Spectrometer Used differential Fourier Transform Spectrometer to measure degree scale anisotropy [9][15]
Balloon-borne Radiometers for Sky Polarisation Observations (BaR-SPoRT) Cancelled Balloon 32, 90 Polarizer / OMT [9]
Berkeley-Illinois-Maryland Association (BIMA) 1986 2004 Ground Hat Creek Radio Observatory, California, USA 70-116; 210-270 SIS [9]
BOOMERanG experiment 1997 2003 Balloon Long-duration balloon above Antarctica 90-420 Bolometer Intermediate scale fluctuations [9]
B-mode RAdiation INterferometer (BRAIN) Never Ground Dome-C, Antarctica
Clover Cancelled Ground 97, 150, 230 Bolometer Cancelled experiment to measure the small scale fluctuations and to search for B-mode polarization. [9]
Cobra 1982 1990 Sounding Rocket University of British Columbia 27-900 Bolometers/ FTS Frequency spectrum of CMB [16][17]
Cosmic Anisotropy Polarization Mapper (CAPMAP) 2002 2008 Ground Crawford Hill Telescope, New Jersey 40, 90 MMIC/HEMT [9]
Cosmic Anisotropy Telescope (CAT) 1994 1997 Ground Mullard Radio Astronomy Observatory 13-17 Interferometer / HEMT Very small scale fluctuations in small regions of the sky. [9]
Cosmic Background Imager (CBI) 2000 2008 Ground Llano de Chajnantor Observatory, Chile 26-36 HEMT Very small scale temperature and polarization anisotropies in a small patch of sky. [9][18]
Cosmology Large Angular Scale Surveyor (CLASS) 2015 Ground Llano de Chajnantor Observatory, Chile 40, 90, 150, 220 TES Bolometer B-mode polarization signal at multipoles from 2 to 100 [9][19]
Primordial Inflation Polarization Explorer (PIPER) Future Balloon 200, 270, 350, 800 TES bolometers B-mode polarization signal [9][20]
COSMOSOMAS 1998 2007 Ground Teide Observatory, Tenerife, Spain 10-18 HEMT Circular scanning experiments for CMB and foregrounds [9][21]
Cosmic Background Explorer (COBE) 1989 1993 Space Earth orbit 31.5, 53, 90 (DMR) Temperature anisotropies; frequency power spectrum; solar system and galactic dust foregrounds. [9][22]
TRIS 1994 2000 Ground 0.6, 0.82, 2.5 CMB frequency power spectrum [9]
COMPASS 2001 2001 Ground Pine Bluff, Wisconsin 26 to 36 HEMT Polarization on degree angular scales [23]
Cosmological Gene (CG) 1999 2009 Ground RATAN-600, Caucasus, Russia 0.6 to 32 HEMT [9][24]
Degree Angular Scale Interferometer (DASI) 1999 2003 Ground South Pole 26-36 HEMT Temperature and polarization anisotropy on degree angular scales [9]
The E and B Experiment (EBEX) 2012 2013 Balloon Antarctica 150-450 Bolometer Inflationary gravitational-wave background (IGB) signal in B-mode polarization [9][25]
Far Infra-Red Survey (FIRS) 1989 1989 Balloon National Scientific Balloon Facility, Fort Sumner, New Mexico 170-680 Bolometer Temperature anisotropy on large angular scales. [9][26]
KU-band Polarization IDentifier (KUPID) 2003 Ground Crawford Hill Telescope, New Jersey 12-18 HEMT [9][27]
Medium Scale Anisotropy Measurement (MSAM) 1992 1997 Balloon 150-650 Bolometer [9]
Millimeter Anisotropy eXperiment IMaging Array (MAXIMA) 1995, 1998, 1999 1999 Balloon Near Palestine, Texas 150-420 Bolometer Intermediate scale temperature fluctuations. [9]
Millimeter Interferometer (MINT) 2001 2002 Ground Cerro Toco, Chile 145 SIS Temperature anisotropies around multipole 1500 [9][28]
Millimeter-Wave Bolometric Interferometer (MBI-B) Future Ground 90 Bolometer [9]
Mobile Anisotropy Telescope (MAT) 1997, 1998 1998 Ground Cerro Toco, Chile 30-140 HEMT / SIS [9][29]
Polarization Observations of Large Angular Regions (POLAR) 2000 2000 Ground Pine Bluff, Wisconsin, USA 26-46 HEMT Polarization at large angular scales [9][30]
POLARBEAR 2012 Ground Chajnantor plateau (Chile) 150 Antenna-coupled TES CMB Polarization. Primordial and lensed B-modes. [9]
Polatron Never Ground 100 Bolometer [9]
Princeton I, Q, and U Experiment (PIQUE) 2002 2002 Ground Princeton University 90 Bolometer [9]
Python 1992 1997 Ground South Pole 30-90 HEMT / Bolometer Temperature anisotropy on intermediate angular scales [9][31]
QMAP 1996 1996 Balloon 30-140 HEMT / SIS [9][32]
QUaD 2005 2007 Ground South Pole 100, 150 Bolometer Polarization at intermediate angular scale [9]
Qubic Future Ground 97, 150, 230 Bolometer B-mode polarization on intermediate angular scale.
Q/U Imaging ExperimenT (QUIET) 2008 2010 Ground Llano de Chajnantor Observatory, Chile 40, 90 HEMT [9][33]
RELIKT-1 1983 1984 Space Earth orbit 37 Temperature anisotropies [9]
Saskatoon experiment 1993 1995 Ground Saskatchewan 26-46 HEMT [9]
Sky Polarization Observatory (SPOrt) Cancelled Space International Space Station 22-90 Polarization [9]
South Pole Telescope 2006 Ground South Pole Small scale temperature and polarization. [9]
SPIDER 2015 Balloon Antarctica 90, 150, 220 Bolometer Large scale polarization. [9]
Sunyaev-Zeldovich Array (SZA) 2004 2008 Ground Owens Valley Radio Observatory 26-36; 85-115 Interferometer Produced sensitive CMB anisotropy constraints at l ~ 4000, measured the SZ effect in 100s of galaxy clusters. Now part of CARMA [9]
MUltiplexed Squid/Tes Array for Ninety Gigahertz (MUSTANG) 2007 Ground 90 TES bolometers Sunyaev-Zeldovich effect [9]
Sunyaev-Zeldovich Infrared Experiment (SuZIE) 1996 Ground Caltech Submillimeter Observatory, Mauna Kea, Hawaii 150, 220, 350 Bolometer SZ effect [9]
Tenerife Experiment 1984 2000 Ground Tenerife 10, 15, 33 HEMT Temperature anisotropies from degree to arcminute angular scales [9]
TopHat 2001 2001 Balloon Antarctica 150-720 Bolometer [9][34][35]
Very Small Array 2002 2008 Ground Tenerife 26-36 Interferometer / HEMT Intermediate and small scale fluctuations in small regions of the sky. [9][36]
Wilkinson Microwave Anisotropy Probe (WMAP) 2001 2010 Space Lagrange 2 23-94 HEMT Temperature anisotropies; Polarization [9]
Planck 2009 2013 Space Lagrange 2 30-857 HEMT / Bolometer Temperature and polarization anisotropies; foregrounds [9]

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