Large area surveys have detected significant samples of galaxy clusters that can be used to constrain cosmological parameters , provided that the masses of the clusters are measured robustly .
To improve the calibration of cluster masses using weak gravitational lensing we present new results for 48 clusters at 0.05 < z < 0.15 , observed as part of the Multi Epoch Nearby Cluster Survey ( MENeaCS ) , and reevaluate the mass estimates for 52 clusters from the Canadian Cluster Comparison Project ( CCCP ) .
Updated high-fidelity photometric redshift catalogues of reference deep fields are used in combination with advances in shape measurements and state-of-the-art cluster simulations , yielding an average systematic uncertainty in the lensing signal below 5 % , similar to the statistical uncertainty for our cluster sample .
We derive a scaling relation with Planck measurements for the full sample and find a bias in the Planck masses of 1 - b = 0.84 \pm 0.04 .
We find no statistically significant trend of the mass bias with redshift or cluster mass , but find that different selections could change the bias by up to 1.5 \sigma .
We find a gas fraction of 0.139 \pm 0.014 for 8 relaxed clusters in our sample , which can also be used to infer cosmological parameters .