Cross-correlating Planck tSZ with RCSLenS weak lensing: implications for cosmology and AGN feedback

We present measurements of the spatial mapping between (hot) baryons and the total matter in the Universe, via the cross-correlation between the thermal Sunyaev-Zeldovich (tSZ) map from Planck and the weak gravitational lensing maps from theRed Cluster Sequence Lensing Survey (RCSLenS). The cross-correlations are performed on the map level where all the sources (including diffuse intergalactic gas) contribute to the signal. We consider two configuration-space correlation function estimators,. xi(y-k) and xi(y-gamma t), and a Fourier-space estimator, C-l(y-k), in our analysis. We detect a significant correlation out to 3 degrees of angular separation on the sky. Based on statistical noise only, we can report 13 sigma and 17 sigma detections of the cross-correlation using the configuration-space y-k and y-gamma(t) estimators, respectively. Including a heuristic estimate of the sampling variance yields a detection significance of 7 sigma and 8 sigma, respectively. A similar level of detection is obtained from the Fourier-space estimator, C-l(y-k). As each estimator probes different dynamical ranges, their combination improves the significance of the detection. We compare our measurements with predictions from the cosmo-OverWhelmingly 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 7-yr best-fitting 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.