XMM-Newton study of the lensing cluster of galaxies CL 0024+17 ^*,**

¹ Max-Planck-Institut für extraterrestrische Physik, Giessenbachstraße, 85748 Garching, Germany e-mail: yyzhang@mpe.mpg.de
² Institut d'Astrophysique de Paris, 98bis Bd. Arago, 75014 Paris, France
³ Observatoire Midi-Pyrénées, Laboratoire d'Astrophysique, MR 5572, 14 avenue E. Belin, 31400 Toulouse, France
⁴ Harvard-Smithsonian Center for Astrophysics (CFA), 60 Garden Street, Cambridge, MA 02138, USA

Received: 14 May 2004
Accepted: 27 August 2004

Abstract

We present a detailed gravitational mass measurement based on the XMM-Newton imaging spectroscopy analysis of the lensing cluster of galaxies CL 0024+17 at . The emission appears approximately symmetric. However, on the scale of  some indication of elongation is visible in the northwest-southeast (NW-SE) direction from the hardness ratio map (HRM). Within , we measure a global gas temperature of 3.52 ± 0.17 keV, metallicity of 0.22 ± 0.07, and bolometric luminosity of 2.9 ± 0.1   erg s^-1. We derive a temperature distribution with an isothermal temperature of 3.9 keV to a radius of  and a temperature gradient in the outskirts (). Under the assumption of hydrostatic equilibrium, we measure gravitational mass and gas mass fraction to be  ± 0.3  10¹⁴  and  ± at  Mpc using the observed temperature profile. The complex structure in the core region is the key to explaining the discrepancy in gravitational mass determined from XMM-Newton X-ray observations and HST optical lensing measurements.