The Atacama Cosmology Telescope: DR4 Maps and Cosmological Parameters
We present new arcminute-resolution maps of the Cosmic Microwave Background temperature and polarization anisotropy from the Atacama Cosmology Telescope, using data taken from 2013-2016 at 98 and 150 GHz. The maps cover more than 17,000 deg\(^2\), the deepest 600 deg\(^2\) with noise levels below 10...
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Published in | arXiv.org |
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Main Authors | , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , |
Format | Paper Journal Article |
Language | English |
Published |
Ithaca
Cornell University Library, arXiv.org
03.12.2020
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Subjects | |
Online Access | Get full text |
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Summary: | We present new arcminute-resolution maps of the Cosmic Microwave Background temperature and polarization anisotropy from the Atacama Cosmology Telescope, using data taken from 2013-2016 at 98 and 150 GHz. The maps cover more than 17,000 deg\(^2\), the deepest 600 deg\(^2\) with noise levels below 10 \(\mu\)K-arcmin. We use the power spectrum derived from almost 6,000 deg\(^2\) of these maps to constrain cosmology. The ACT data enable a measurement of the angular scale of features in both the divergence-like polarization and the temperature anisotropy, tracing both the velocity and density at last-scattering. From these one can derive the distance to the last-scattering surface and thus infer the local expansion rate, \(H_0\). By combining ACT data with large-scale information from WMAP we measure \(H_0 = 67.6 \pm 1.1\) km/s/Mpc, at 68% confidence, in excellent agreement with the independently-measured Planck satellite estimate (from ACT alone we find \(H_0 = 67.9 \pm 1.5\) km/s/Mpc). The \(\Lambda\)CDM model provides a good fit to the ACT data, and we find no evidence for deviations: both the spatial curvature, and the departure from the standard lensing signal in the spectrum, are zero to within 1\(\sigma\); the number of relativistic species, the primordial Helium fraction, and the running of the spectral index are consistent with \(\Lambda\)CDM predictions to within \(1.5 - 2.2\sigma\). We compare ACT, WMAP, and Planck at the parameter level and find good consistency; we investigate how the constraints on the correlated spectral index and baryon density parameters readjust when adding CMB large-scale information that ACT does not measure. The DR4 products presented here will be publicly released on the NASA Legacy Archive for Microwave Background Data Analysis. |
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ISSN: | 2331-8422 |
DOI: | 10.48550/arxiv.2007.07288 |