Constraining cosmology with a new all-sky Compton parameter map from the Planck PR4 data

TL;DR

This paper presents a new all-sky Compton parameter map from Planck PR4 data, improving noise and systematics, and uses it to derive cosmological parameters consistent with weak-lensing observations.

Contribution

The paper introduces an improved all-sky tSZ y-map from Planck PR4 data with reduced noise and systematics, enabling refined cosmological analysis.

Findings

tSZ power spectrum dominates multipole range 60-600

Derived S8=0.764 with uncertainties, consistent with weak-lensing

Results are compatible with Planck CMB within 2 sigma

Abstract

We constructed a new all-sky Compton parameter map (y-map) of the thermal Sunyaev-Zel'dovich (tSZ) effect from the 100 to 857 GHz frequency channel maps delivered within the Planck data release 4. The improvements in terms of noise and systematic effects translated into a y-map with a noise level smaller by ~7% compared to the maps released in 2015, and with significantly reduced survey stripes. The produced 2020 y-map is also characterized by residual foreground contamination, mainly due to thermal dust emission at large angular scales and to CIB and extragalactic point sources at small angular scales. Using the new Planck data, we computed the tSZ angular power spectrum and found that the tSZ signal dominates the y-map in the multipole range, 60 < l < 600. We performed the cosmological analysis with the tSZ angular power spectrum and found S8=0.764+0.015-0.018(stat)+0.031-0.016(sys), including systematic uncertainties from a hydrostatic mass bias and pressure profile model. The S8 value may differ by +-0.016 depending on the hydrostatic mass bias model and by +0.021 depending on the pressure profile model used for the analysis. The obtained value is fully consistent with recent KiDS and DES weak-lensing observations. While our result is slightly lower than the Planck CMB one, it is consistent with the latter within 2 sigma.