Scaling relations and mass calibration of the X-ray luminous galaxy clusters at redshift ~0.2: XMM-Newton observations ^*,**

¹ Max-Planck-Institut für extraterrestrische Physik, Giessenbachstraße, 85748 Garching, Germany e-mail: yyzhang@mpe.mpg.de
² OAMP, Laboratoire d'Astrophysique de Marseille, traverse du Siphon, 13012 Marseille, France
³ Caltech-Astronomy, MC105-24, Pasadena, CA 91125, USA
⁴ School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham, B152TT, UK
⁵ AIFA, Universität Bonn, Auf dem Hügel 71, 53121 Bonn, Germany
⁶ Kapteyn Astronomical Institute, PO Box 800, 9700AV Groningen, The Netherlands
⁷ Observatoire Midi-Pyrénées, Laboratoire d'Astrophysique, UMR 5572, 14 avenue E. Belin, 31400 Toulouse, France

Received: 13 October 2006
Accepted: 20 February 2007

Abstract

We present the X-ray properties and scaling relations of a flux-limited morphology-unbiased sample of 12 X-ray luminous galaxy clusters at redshift around 0.2 based on XMM-Newton observations. The scaled radial profiles are characterized by a self-similar behavior at radii outside the cluster cores (>) for the temperature (), surface brightness, entropy (), gas mass and total mass. The cluster cores contribute up to 70% of the bolometric X-ray luminosity. The X-ray scaling relations and their scatter are sensitive to the presence of the cool cores. Using the X-ray luminosity corrected for the cluster central region and the temperature measured excluding the cluster central region, the normalization agrees to better than 10% for the cool core clusters and non-cool core clusters, irrelevant to the cluster morphology. No evolution of the X-ray scaling relations was observed comparing this sample to the nearby and more distant samples. With the current observations, the cluster temperature and luminosity can be used as reliable mass indicators with the mass scatter within 20%. Mass discrepancies remain between X-ray and lensing and lead to larger scatter in the scaling relations using the lensing masses (e.g. ~40% for the luminosity–mass relation) than using the X-ray masses (<20%) due to the possible reasons discussed.