An XMM-Newton study of the RGH 80 galaxy group

¹ Max-Planck-Institut für extraterrestrische Physik, Giessenbachstraße, 85748 Garching, Germany
² National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China
³ Department of Physics, Tokyo University of Science, 1-3 Kagurazaka, Shinjyuku-ku, Tokyo 162-8601, Japan

Corresponding author: Y.-J. Xue, yxue@mpe.mpg.de

Received: 27 November 2003
Accepted: 27 February 2004

Abstract

We present an X-ray study of the galaxy group RGH 80, observed by XMM-Newton . The X-ray emission of the gas is detected out to ~ kpc, corresponding to ~. The group is relatively gas rich and luminous with respect to its temperature of 1.01 ± 0.01 keV. Using the deprojected spectral analysis, we find that the temperature peaks at ~1.3 keV around , and then decreases inwards to 0.83 keV at the center and outwards to ~ of the peak value at large radii. Within the central ~60 kpc of the group where the gas cooling time is less than the Hubble time, a two-temperature model with temperatures of 0.82 and 1.51 keV and the Galactic absorption gives the best fit of the spectra, with ~ volume occupied by the cool component. We also derive the gas entropy distribution, which is consistent with the prediction of cooling and/or internal heating models. Furthermore, the abundances of O, Mg, Si, S and Fe decrease monotonically with radius. With the observed abundance ratio pattern, we estimate that ~ or ~ of the iron mass is contributed by SN Ia, depending on the adopted SN II models.