A CFH12k lensing survey of X-ray luminous galaxy clusters^*

II. Weak lensing analysis and global correlations

¹ Laboratoire d'Astrophysique de Toulouse-Tarbes, CNRS-UMR 5572 and Université Paul Sabatier Toulouse III, 14 avenue Belin, 31400 Toulouse, France e-mail: soucail@ast.obs-mip.fr
² Laboratoire d'Astrodynamique, d'Astrophysique et d'Aéronomie de Bordeaux, CNRS-UMR 5804 and Université de Bordeaux I, 2 rue de l'Observatoire, BP 89, 33270 Floirac, France
³ Laboratoire d'Astrophysique de Marseille, OAMP, CNRS-UMR 6110, Traverse du Siphon, BP 8, 13376 Marseille Cedex 12, France
⁴ Department of Astronomy, California Institute of Technology, Mail Code 105-24, Pasadena, CA 91125, USA
⁵ Argelander-Institut für Astronomie, Universität Bonn, Auf dem Hügel 71, 53121 Bonn, Germany (Founded by merging of the Sternwarte, Radioastronomisches Institut and Institut für Astrophysik und Extraterrestrische Forschung der Universität Bonn)
⁶ Kapteyn Astronomical Institute, PO Box 800, 9700 AV Groningen, The Netherlands
⁷ Institute for Astronomy, University of Hawaii, 2680 Woodlawn Dr, Honolulu, HI 96822, USA
⁸ Institute for Computational Cosmology, Department of Physics, Durham University, South Road, Durham DH1 3LE, UK
⁹ School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK

Received: 9 March 2007
Accepted: 9 May 2007

Abstract

Aims.We present a wide-field multi-color survey of a homogeneous sample of eleven clusters of galaxies for which we measure total masses and mass distributions from weak lensing. This sample, spanning a small range in both X-ray luminosity and redshift, is ideally suited to determining the normalisation of scaling relations between X-ray properties of clusters and their masses (the and the relations) and also estimating the scatter in these relations at a fixed luminosity.

Methods.The eleven clusters in our sample are all X-ray luminous and span a narrow redshift range at z = 0.21 ± 0.04. The weak lensing analysis of the sample is based on ground-based wide-field imaging obtained with the CFH12k camera on CFHT. We use the methodology developed and applied previously on the massive cluster Abell 1689. A Bayesian method, implemented in the Im2shape software, is used to fit the shape parameters of the faint background galaxies and to correct for PSF smearing. A multi-color selection of the background galaxies is applied to retrieve the weak lensing signal, resulting in a background density of sources of ~10 galaxies per square arc minute. With the present data, shear profiles are measured in all clusters out to at least 2 Mpc (more than 15´ from the center) with high confidence. The radial shear profiles are fitted with different parametric mass profiles and the virial mass M₂₀₀ is estimated for each cluster and then compared to other physical properties.

Results.Scaling relations between mass and optical luminosity indicate an increase of the ratio with luminosity () and a relation scaling as while the normalization of the relation is close to the one expected from hydrodynamical simulations of cluster formation as well as previous X-ray analyses. We suggest that the dispersion in the and relations reflects the different merging and dynamical histories for clusters of similar X-ray luminosities and intrinsic variations in their measured masses. Improved statistics of clusters over a wider mass range are required for a better control of the intrinsic scatter in scaling relations.