High resolution soft X-ray spectroscopy of M 87 with the reflection grating spectrometers on

¹ Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey RH5 6NT, UK
² Columbia Astrophysics Laboratory, 550 W. 120th St., New York, NY10027, USA
³ SRON National Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
⁴ CEA Saclay, Service d'Astrophysique, 91191 Gif-sur-Yvette, France
⁵ Max-Planck-Institut für Extraterrestrische Physik, Germany
⁶ Department of Physics, University of California, Santa Barbara, CA 93106, USA
⁷ NASA/GSFC, Code 662, Greenbelt, MD 20771, USA
⁸ NIS-2, MS D436, Los Alamos National Laboratory, USA
⁹ Department of Physics, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, UK

Corresponding author: I. Sakelliou, irini@star.sr.bham.ac.uk

Received: 7 February 2002
Accepted: 12 June 2002

Abstract

We present high-resolution X-ray spectroscopic observations of M 87 with the Reflection Grating Spectrometers on XMM-Newton. We detect strong K-shell line emission from N, O, Ne, Mg, some emission from He-like Si, a fully resolved set of Fe L-shell emission spectra, and some emission from C. The angular intensity distributions of the strong emission lines are detectably resolved on scales . The gas in the inner arcmin of M 87 has a multi-phase structure, as indicated by the similarity of the emission line profiles of Fe L shell ions with widely separated ionization potentials. The global Fe L spectrum is approximately consistent with an isothermal plasma at  keV, in addition to a component with a temperature distribution appropriate to an isobaric cooling flow, but with a minimum temperature cutoff of  eV. The behaviour of this cooling-flow component is qualitatively similar to what is seen in other cooling flow clusters. Finally, we do not find any strong evidence for a spatial variation in abundances due to resonance scattering redistribution in the inner arcminute of the core.