$X+y$: insights on gas thermodynamics from the combination of X-ray and thermal Sunyaev-Zel'dovich data cross-correlated with cosmic shear

TL;DR

This study combines cosmic shear, tSZ, and X-ray data to develop a physical model of hot gas in galaxy clusters, constraining its thermodynamic properties and distribution while addressing data tensions.

Contribution

It introduces a simple yet effective model that jointly describes multiple observational probes of hot gas, incorporating contamination and non-thermal effects for improved accuracy.

Findings

Constraints on the halo gas expulsion mass scale ($ ext{log}_{10}(M_c)=14.83^{+0.16}_{-0.23}$)

Measurement of the polytropic index ($ ext{Gamma}=1.144^{+0.016}_{-0.013}$)

Estimate of the central gas temperature ratio ($ ext{alpha}_T=1.30^{+0.15}_{-0.28}$)

Abstract

We measure the cross-correlation between cosmic shear from the third-year release of the Dark Energy Survey, thermal Sunyaev-Zel'dovich (tSZ) maps from Planck, and X-ray maps from ROSAT. We investigate the possibility of developing a physical model able to jointly describe both measurements, simultaneously constraining the spatial distribution and thermodynamic properties of hot gas. We find that a relatively simple model is able to describe both sets of measurements and to make reasonably accurate predictions for other observables (the tSZ auto-correlation, its cross-correlation with X-rays, and tomographic measurements of the bias-weighted mean gas pressure). We show, however, that contamination from X-ray AGN, as well as the impact of non-thermal pressure support, must be incorporated in order to fully resolve tensions in parameter space between different data combinations. We obtain simultaneous constraints on the mass scale at which half of the gas content has been expelled from the halo, $\mathrm{log}_{10}(M_c)=14.83^{+0.16}_{-0.23}$, on the polytropic index of the gas, $\Gamma=1.144^{+0.016}_{-0.013}$, and on the ratio of the central gas temperature to the virial temperature $\alpha_T=1.30^{+0.15}_{-0.28}$.