Tilman Troster | Searcharxiv

arXiv2021

Constraining AGN feedback model with SZ profile

Relativistic jets from AGN have a wide range of impacts on galaxy groups and clusters and are key for understanding their formation and physical properties. However, this non-gravitational process is not well understood. Galaxy groups with shallow gravitational potentials are ideal laboratories to study and constrain the AGN feedback model. We studied hot gas in ~66,000 SDSS LRG halos with an average halo mass of 3 x 10^13 Msun using the Planck tSZ map. We have detected their average tSZ radial profile at ~17 sigma and compared it with the cosmo-OWLS cosmological hydrodynamical simulations with different AGN feedback models. The best agreement has been obtained for the AGN 8.0 model in the simulations. We have also compared our measured tSZ profile with the prediction from the universal pressure profile assuming the self-similar relation and found them consistent if the model accounts for the clustering of neighboring haloes via a two-halo term.

astro-ph.CO↗

arXiv2020

Probing the cluster pressure profile with thermal Sunyaev-Zeldovich effect and weak lensing cross-correlation

We confront the universal pressure profile (UPP) proposed by~\citet{Arnaud10} with the recent measurement of the cross-correlation function of the thermal Sunyaev-Zeldovich (tSZ) effect from Planck and weak gravitational lensing measurement from the Red Cluster Sequence lensing survey (RCSLenS). By using the halo model, we calculate the prediction of $ξ^{y-κ}$ (lensing convergence and Compton-$y$ parameter) and $ξ^{y-γ_{\rm t}}$ (lensing shear and Compton-$y$ parameter) and fit the UPP parameters by using the observational data. We find consistent UPP parameters when fixing the cosmology to either WMAP 9-year or Planck 2018 best-fitting values. The best constrained parameter is the pressure profile concentration $c_{500}=r_{500}/r_{\rm s}$, for which we find $c_{500} = 2.68^{+1.46}_{-0.96}$ (WMAP-9) and $c_{500} = 1.91^{+1.07}_{-0.65}$ (Planck-2018) for the $ξ^{y-γ_t}$ estimator. The shape index for the intermediate radius region $α$ parameter is constrained to $α=1.75^{+1.29}_{-0.77}$ and $α= 1.65^{+0.74}_{-0.5}$ for WMAP-9 and Planck-2018 cosmologies, respectively. Propagating the uncertainties of the UPP parameters to pressure profiles results in a factor of $3$ uncertainty in the shape and magnitude. Further investigation shows that most of the signal of the cross-correlation comes from the low-redshift, inner halo profile ($r \leqslant r_{\rm vir}/2$) with halo mass in the range of $10^{14}$--$10^{15}\,{\rm M}_{\odot}$, suggesting that this is the major regime that constitutes the cross-correlation signal between weak lensing and tSZ.

astro-ph.CO↗