Letter to the Editor

3D simulations of supernova remnants evolution including non-linear particle acceleration

¹ Laboratoire AIM (CEA/Irfu, CNRS/INSU, Université Paris VII), CEA Saclay, Bât. 709, 91191 Gif-sur-Yvette, France e-mail: g.ferrand@cea.fr
² Institute for Theoretical Physics, University of Zürich, 8057 Zürich, Switzerland
³ LUTh, Observatoire de Paris, CNRS-UMR8102 et Université Paris VII, 92195 Meudon Cedex, France
⁴ Lunar and Planetary Lab & Dept. of Physics, University of Arizona, Tucson, AZ, 85721, USA

Received: 13 November 2009
Accepted: 19 December 2009

Abstract

If a sizeable fraction of the energy of supernova remnant shocks is channeled into energetic particles (commonly identified with Galactic cosmic rays), then the morphological evolution of the remnants must be distinctly modified. Evidence of such modifications has been recently obtained with the Chandra and XMM-Newton X-ray satellites. To investigate these effects, we coupled a semi-analytical kinetic model of shock acceleration with a 3D hydrodynamic code (by means of an effective adiabatic index). This enables us to study the time-dependent compression of the region between the forward and reverse shocks due to the back reaction of accelerated particles, concomitantly with the development of the Rayleigh-Taylor hydrodynamic instability at the contact discontinuity. Density profiles depend critically on the injection level η of particles: for modifications are weak and progressive, for modifications are strong and immediate. Nevertheless, the extension of the Rayleigh-Taylor unstable region does not depend on the injection rate. A first comparison of our simulations with observations of Tycho's remnant strengthens the case for efficient acceleration of protons at the forward shock.