Max-Planck-Institut für extraterrestrische Physik, Giessenbachstraße, 85748 Garching, Germany e-mail: email@example.com
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
Accepted: 27 August 2004
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.
Key words: galaxies: clusters: individual: CL 0024+17 / cosmology: dark matter / gravitational lensing / cosmology: observations / X-rays: galaxies: clusters
This work is based on observations made with the XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA member states and the USA (NASA).
© ESO, 2005