Exploring the thermal energy contents of the intergalactic mediumwith the Sunyaev–Zeldovich effect

• DOI: 10.1093/mnras/sty2126
• Publication Date: 2018-08-05T07:06:42Z
• Authors: S H Lim; H J Mo; Huiyuan Wang; Xiaohu Yang
• Keywords: 13. Climate action; Astrophysics of Galaxies (astro-ph.GA); 0103 physical sciences; FOS: Physical sciences; Astrophysics - Astrophysics of Galaxies; 01 natural sciences; 7. Clean energy

We examine the thermal energy contents of intergalactic medium (IGM) over three orders magnitude in both mass density and gas temperature using Sunyaev-Zel'dovich effect (tSZE). The analysis is based on {\it Planck} tSZE map cosmic field, reconstructed for SDSS DR7 volume sampled a grid cubic cells $(1h^{-1}{\rm Mpc})^3$, together with matched filter technique employed to maximize signal-to-noise. Our results show that pressure - relation IGM roughly power law given by an adiabatic equation state, indication steepening at densities higher than about $10$ times mean universe. implied average $\sim 10^4\,{\rm K}$ regions density, $\rho_{\rm m} \sim {\overline\rho}_{\rm m}$, increasing $10^5\,{\rm 10\,{\overline\rho}_{\rm $>10^{6}\,{\rm 100\,{\overline\rho}_{\rm m}$. At content also found be stronger tidal fields, likely due shock heating formation large scale structure and/or feedback from galaxies AGNs. A comparison hydrodynamic simulations suggests current data can already provide interesting constraints galaxy formation.