An XMM-Newton study of the sub-structure in M 87's halo

¹ Service d'Astrophysique, CEA Saclay, L'Orme des Merisiers, Bât. 709, 91191 Gif-sur-Yvette Cedex, France
² Max-Planck-Institut für Extraterrestrial Physik, 85748 Garching, Germany
³ Department of Physics, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, UK
⁴ Laboratory of High Energy Astrophysics, Code 660, NASA/Goddard Space Flight Center, Greenbelt, MD 20771, USA
⁵ Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT, UK
⁶ Istituto di Fisica Cosmica, via Bassini 15, 20133, Milano, Italy
⁷ SOC, Villafranca, Apartado 50727, 28080 Madrid, Spain
⁸ University of California, Santa Barbara, USA
⁹ Departement of Physics and Astronomy, The University of Leicester, Leicester LE1 7RH, UK
¹⁰ NIS-2, MS D436, Los Alamos National Laboratory, Los Alamos, NM 87545, USA

Corresponding author: E. Belsole, ebelsole@cea.fr

Received: 4 October 2000
Accepted: 10 November 2000

Abstract

The high signal to noise and good point spread function of XMM have allowed the first detailed study of the interaction between the thermal and radio emitting plasma in the central regions of M 87. We show that the X-ray emitting structure, previously seen by ROSAT, is thermal in nature and that the east and southwest extensions in M 87's X-ray halo have a significantly lower temperature ( keV) than the surrounding ambient medium ( keV). There is little or no evidence for non-thermal emission with an upper limit on the contribution of a power law component of spectral index flatter than 3 being less than 1% of the flux in the region of the radio lobes.