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arXiv · 0804.4652

A weak lensing analysis of the Abell 2163 cluster

Abstract

Weak lensing analysis is applied to a deep, one square degree r-band CFHT-Megacam image of the Abell 2163 field. The observed shear is fitted with Single Isothermal Sphere and Navarro-Frenk-White models to obtain the velocity dispersion and the mass, respectively; in addition, aperture densitometry is also used to provide a mass estimate at different distances from the cluster centre. The luminosity function is finally derived, allowing to estimate the mass/luminosity ratio. Previous weak lensing analyses performed at smaller scales produced somewhat contradictory results. The mass and velocity dispersion obtained in the present paper are compared and found to be in good agreement with the values computed by other authors from X-ray and spectroscopic data.

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M. Radovich, E. Puddu, A. Romano, A. Grado, F. Getman. 2008-04-29. A weak lensing analysis of the Abell 2163 cluster. https://doi.org/10.1051/0004-6361:200809731

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