A weak-lensing analysis of the Abell 2163 cluster*
1
INAF - Osservatorio Astronomico di Capodimonte, via Moiariello 16, 80131 Napoli, Italy e-mail: radovich@oacn.inaf.it
2
INAF - VSTceN, via Moiariello 16, 80131 Napoli, Italy
Received:
6
March
2008
Accepted:
28
April
2008
Aims. We attempt to measure the main physical properties (mass, velocity dispersion, and total luminosity) of the cluster Abell 2163.
Methods. A 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 used to provide a mass estimate at different distances from the cluster centre. The luminosity function is derived, which enables us to estimate the mass/luminosity ratio.
Results. Weak-lensing analyses of this cluster, on smaller scales, have produced results that conflict with each other. The mass and velocity dispersion obtained in the present paper are compared and found to agree well with values computed by other authors from X-ray and spectroscopic data.
Key words: galaxies: clusters: individual: Abell 2163 / galaxies: fundamental parameters / cosmology: dark matter
Based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council (NRC) of Canada, the Institute National des Sciences de l'Univers of the Centre National de la Recherche Scientifique of France, and the University of Hawaii.
© ESO, 2008