The Atacama Cosmology Telescope: DR4 maps and cosmological parameters

By S. Aiola, E. Calabrese, L. Maurin, S. Naess, B. Schmitt, M. Abitbol, G. Addison, P. Ade, D. Alonso, M. Amiri and 130 more. Journal of Cosmology and Astroparticle Physics, 2020

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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 deg2, the deepest 600 deg2 with noise levels below 10μK-arcmin. We use the power spectrum derived from almost 6,000 deg2 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, H0. By combining ACT data with large-scale information from WMAP we measure H0=67.6± 1.1 km/s/Mpc, at 68% confidence, in excellent agreement with the independently-measured Planck satellite estimate (from ACT alone we find H0=67.9± 1.5 km/s/Mpc). The ΛCDM 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 1σ; the number of relativistic species, the primordial Helium fraction, and the running of the spectral index are consistent with ΛCDM predictions to within 1.5–2.2σ. 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.

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/bb9c59f2466d17d856f6c4a35ebe195fa1f9c371

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Citations in the corpus

Measurements of the E -mode polarization and temperature- E -mode correlation of the CMB from SPT-3G 2018 data (2021, background): “Similar trends for low- and high-multipole data as well as EE and TE spectra were reported by H18 and [29].”
KiDS-1000 Cosmology: Multi-probe weak gravitational lensing and spectroscopic galaxy clustering constraints (2020, methodology): “…that we have reported, and the overall trend in the literature, we would argue that we are reaching an uncomfortable 16 A recent independent Atacama Cosmology Telescope CMB analysis reports S 8 = 0.830 ± 0.043, in agreement with the Planck constraint of S 8 = 0.834 ± 0.016 (ACT, Aiola et al. 2020).”
CMB-S4: Forecasting Constraints on Primordial Gravitational Waves (2020, background): “…measuring the CMB polarization to high precision on a range of scales, and attempting to constrain the tensor-to-scalar ratio, including ACT (Aiola et al. 2020), BICEP/Keck (BICEP2/Keck Array Collabora- tions X 2018), CLASS (Harrington et al. 2016), POLARBEAR/Simons Array (Suzuki et al.…”
Hubble Tension: The Evidence of New Physics (2023, methodology): “In addition, there exists a lot of H0 predictions adopting other CMB experiments from the ground, including the South Pole Telescope (SPTPol) [66,102] and Atacama Cosmology Telescope (ACT) [103].”
The Atacama Cosmology Telescope: A Measurement of the DR6 CMB Lensing Power Spectrum and Its Implications for Structure Growth (2023, methodology): “The dashed lines in the figure show that the differences between the ACT+WMAP and the fiducial spectra are significantly reduced after these corrections are applied.”
A buyer’s guide to the Hubble constant (2021, unknown): “2020), but appears to be absent in the Atacama Cosmology Telescope (ACT) data (Aiola et al. 2020).”