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Cosmological Parameters from the QUaD CMB Polarization Experiment

Castro, P. G. and Ade, P. and Bock, J. and Bowden, M. and Brown, M. L. and Cahill, G. and Church, S. and Culverhouse, T. and Friedman, R. B. and Ganga, K. and Gear, W. K. and Gupta, S. and Hinderks, J. and Kovac, J. and Lange, A. E. and Leitch, E. and Melhuish, S. J. and Memari, Y. and Murphy, J. A. and Orlando, A. and Pryke, C. and Schwarz, R. and O'Sullivan, C. and Piccirillo, L. and Rajguru, N. and Rusholme, B. and Taylor, A. N. and Thompson, K. L. and Turner, A. H. and Wu, E. Y. S. and Zemcov, M. (2009) Cosmological Parameters from the QUaD CMB Polarization Experiment. Astrophysical Journal, 701 (2). pp. 857-864. ISSN 0004-637X.

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In this paper, we present a parameter estimation analysis of the polarization and temperature power spectra from the second and third season of observations with the QUaD experiment. QUaD has for the first time detected multiple acoustic peaks in the E-mode polarization spectrum with high significance. Although QUaD-only parameter constraints are not competitive with previous results for the standard six-parameter ΛCDM cosmology, they do allow meaningful polarization-only parameter analyses for the first time. In a standard six-parameter ΛCDM analysis, we find the QUaD TT power spectrum to be in good agreement with previous results. However, the QUaD polarization data show some tension with ΛCDM. The origin of this 1σ-2σ tension remains unclear, and may point to new physics, residual systematics, or simple random chance. We also combine QUaD with the five-year WMAP data set and the SDSS luminous red galaxies 4th data release power spectrum, and extend our analysis to constrain individual isocurvature mode fractions, constraining cold dark matter density, α_(cdmi) < 0.11 (95% confidence limit (CL)), neutrino density, α_(ndi) < 0.26 (95% CL), and neutrino velocity, α_(nvi) < 0.23 (95% CL), modes. Our analysis sets a benchmark for future polarization experiments.

Item Type:Article
Related URLs:
URLURL TypeDescription
Bock, J.0000-0002-5710-5212
Rusholme, B.0000-0001-7648-4142
Zemcov, M.0000-0001-8253-1451
Additional Information:© 2009. The American Astronomical Society. Received 2008 December 19; accepted 2009 May 11; published 2009 July 28. QUaD is funded by the National Science Foundation in the USA, through grants AST-0096778, ANT-0338138, ANT-0338335, and ANT-0338238, by the UK Science and Technology Facilities Council (STFC) and its predecessor the Particle Physics and Astronomy Research Council (PPARC), and by the Science Foundation Ireland. J.R.H. acknowledges the support of an NSF Graduate Research Fellowship, a Stanford Graduate Fellowship and a NASA Postdoctoral Fellowship. C.P. and J.E.C. acknowledge partial support from the Kavli Institute for Cosmological Physics through the grant NSF PHY-0114422. E.Y.W. acknowledges receipt of an NDSEG fellowship.Y.M. acknowledges support from a SUPAPrize studentship. P.G.C. acknowledges funding from the Fundação para a Ciência e a Tecnologia. M.Z. acknowledges support from a NASA Postdoctoral Fellowship. This work has made use of the resources provided by the Edinburgh Compute and Data Facility (ECDF) that is partially supported by the eDIKT initiative. We also thank Licia Verde and Joanna Dunkley for useful discussion.
Funding AgencyGrant Number
Science and Technology Facilities CouncilUNSPECIFIED
Department of DefenseUNSPECIFIED
SUPA Prize studentshipUNSPECIFIED
Fundação para a Ciência e a TecnologiaUNSPECIFIED
e-Science Data, Information and Knowledge TransformationUNSPECIFIED
Particle Physics and Astronomy Research CouncilUNSPECIFIED
Science Foundation IrelandUNSPECIFIED
Stanford UniversityUNSPECIFIED
Subject Keywords:cosmic microwave background; cosmological parameters; methods: statistical; polarization
Issue or Number:2
Record Number:CaltechAUTHORS:20090825-104125123
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Official Citation:Cosmological Parameters from the QUAD CMB Polarization Experiment P. G. Castro, P. Ade, J. Bock, M. Bowden, M. L. Brown, G. Cahill, S. Church, T. Culverhouse, R. B. Friedman, K. Ganga, W. K. Gear, S. Gupta, J. Hinderks, J. Kovac, A. E. Lange, E. Leitch, S. J. Melhuish, Y. Memari, J. A. Murphy, A. Orlando, C. Pryke, R. Schwarz, C. O'Sullivan, L. Piccirillo, N. Rajguru, B. Rusholme, A. N. Taylor, K. L. Thompson, A. H. Turner, E. Y. S. Wu, M. Zemcov (The QUaD collaboration) 2009 ApJ 701 857-864 doi: 10.1088/0004-637X/701/2/857
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:15296
Deposited By: Ruth Sustaita
Deposited On:25 Aug 2009 22:57
Last Modified:09 Mar 2020 13:19

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