Crosscorrelating Planck tSZ with RCSLenS weak lensing: implications for cosmology and AGN feedback
Abstract
We present measurements of the spatial mapping between (hot) baryons and the total matter in the Universe, via the crosscorrelation between the thermal SunyaevZeldovich (tSZ) map from Planck and the weak gravitational lensing maps from the Red Cluster Sequence Lensing Survey (RCSLenS). The crosscorrelations are performed on the map level where all the sources (including diffuse intergalactic gas) contribute to the signal. We consider two configurationspace correlation function estimators, ξ^{yκ} and ξ ^ {yγ _{t}}, and a Fourierspace estimator, C_{ℓ}^{yκ}, in our analysis. We detect a significant correlation out to 3° of angular separation on the sky. Based on statistical noise only, we can report 13σ and 17σ detections of the crosscorrelation using the configurationspace yκ and yγ_{t} estimators, respectively. Including a heuristic estimate of the sampling variance yields a detection significance of 7σ and 8σ, respectively. A similar level of detection is obtained from the Fourierspace estimator, C_{ℓ}^{yκ}. As each estimator probes different dynamical ranges, their combination improves the significance of the detection. We compare our measurements with predictions from the cosmoOverWhelmingly Large Simulations suite of cosmological hydrodynamical simulations, where different galactic feedback models are implemented. We find that a model with considerable active galactic nuclei (AGN) feedback that removes large quantities of hot gas from galaxy groups and Wilkinson Microwave Anisotropy Probe 7yr bestfitting cosmological parameters provides the best match to the measurements. All baryonic models in the context of a Planck cosmology overpredict the observed signal. Similar cosmological conclusions are drawn when we employ a halo model with the observed 'universal' pressure profile.
 Publication:

Monthly Notices of the Royal Astronomical Society
 Pub Date:
 October 2017
 DOI:
 10.1093/mnras/stx1659
 arXiv:
 arXiv:1608.07581
 Bibcode:
 2017MNRAS.471.1565H
 Keywords:

 gravitational lensing: weak;
 dark matter;
 largescale structure of Universe;
 Astrophysics  Cosmology and Nongalactic Astrophysics
 EPrint:
 16 pages, 13 figures