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تسجيل مستخدم جديدCCCP and MENeaCS: (updated) weak-lensing masses for 100 galaxy clusters
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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.
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