Speaker
Description
To compare the observations of galaxy clusters with theoretical predictions and thus constrain the cosmological parameters of the underlying model, precise knowledge of cluster masses and redshifts is required. We provide a new $Y_{\text{SZ}} - M_{500}^{Y_X}$ scaling relation using a sample of clusters from the Planck Early Sunyaev-Zeldovich (ESZ) catalogue that was observed in X-rays by Chandra, and compare it to the results of the Planck collaboration obtained from XMM-Newton observations of a subsample of the ESZ. We calibrate a mass bias for the new scaling relation as well as that from the Planck collaboration with a subset of the Planck cosmological cluster sample using published weak-lensing data from the Canadian Cluster Cosmology Project (CCCP) and Multi Epoch Nearby Cluster Survey (MENeaCS). We propose a novel method to account for selection effects . With these mass biases, we obtain $Y_{\text{SZ}} - M_{500}$ scaling relations that we apply to the full Planck cosmological cluster sample, to obtain new constraints on the cosmological parameters. We also provide constraints with a redshift evolution of the scaling relation fitted from the data instead of fixing it to the self-similar value. We find a redshift evolution significantly deviating from the self-similar value, leading to a 1.5$\sigma$ shift of $S_8$. We compare our results to those from recent analyses based on various cosmological probes.
We also plan to have some results using DES data to calibrate the mass bias, and to compare those with the results obtained with CCCP and MENeaCS.
