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Caustic and Weak Lensing Estimators of Galaxy Cluster Masses

Antonaldo Diaferio·Margaret J. Geller·Kenneth J. Rines
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Abstract

There are only two methods for estimating the mass distribution in the outer regions of galaxy clusters, where virial equilibrium does not hold: weak gravitational lensing and identification of caustics in redshift space. For the first time, we apply both methods to three clusters: A2390, MS1358 and Cl 0024. The two measures are in remarkably good agreement out to ~2 Mpc/h from the cluster centers. This result demonstrates that the caustic technique is a valuable complement to weak lensing. With a few tens of redshifts per (Mpc/h)^2 within the cluster, the caustic method is applicable for any z<~0.5.

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Antonaldo Diaferio, Margaret J. Geller, Kenneth J. Rines. 2005-06-23. Caustic and Weak Lensing Estimators of Galaxy Cluster Masses. https://doi.org/10.1086/432880

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