XMM-Newton observations of the non-thermal supernova remnant HESS J1731−347 (G353.6-0.7)

¹ Institut für Astronomie und Astrophysik, Sand 1, 72076 Tübingen, Germany
e-mail: doroshv@astro.uni-tuebingen.de
² Department of Physics, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
³ Research Center for the Early Universe, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
⁴ Laboratoire AIM, IRFU/SAp – CEA/DRF – CNRS, Université Paris Diderot, Bât. 709, CEA-Saclay, Gif-sur-Yvette Cedex, France
⁵ Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, PR China
⁶ Institute of Astronomy and Department of Physics, National Tsing Hua University, Hsinchu, Taiwan
⁷ Department of Physics and Astronomy, University of Calgary, Calgary, Alberta T2N 1N4, Canada

Received: 13 April 2017
Accepted: 5 August 2017

Abstract

We report on the analysis of XMM-Newton observations of the non-thermal shell-type supernova remnant HESS J1731−347 (G353.6-0.7). For the first time the complete remnant shell has been covered in X-rays, which allowed direct comparison with radio and TeV observations. We carried out a spatially resolved spectral analysis of XMM-Newton data and confirmed the previously reported non-thermal power-law X-ray spectrum of the source with negligible variations of spectral index across the shell. On the other hand, the X-ray absorption column is strongly variable and correlates with the CO emission thus confirming that the absorbing material must be in the foreground and reinforcing the previously suggested lower limit on distance. Finally, we find that the X-ray emission of the remnant is suppressed towards the Galactic plane, which points to lower shock velocities in this region, likely due to the interaction of the shock with the nearby molecular cloud.