A two-zone model for the emission from RX J1713.7-3946

Abstract

We study the acceleration and radiation of charged particles in the shock waves of supernova remnants using a recent version of the "box model". According to this, particles are accelerated in an energy-dependent region around the shock by the first order Fermi mechanism and lose energy through radiation. The particle distribution function is obtained from a spatially averaged kinetic equation that treats the energy losses self-consistently. There exists also a second population that consists of those particles that escape behind the shock where they also radiate. The energy distribution of this population is calculated in a similar manner. The application of the model to the supernova remnant RX J1713.7-3946, which was recently confirmed as a TeV source by H.E.S.S., shows that the X-ray emission can be attributed to electron synchrotron radiation while in gamma-rays there are contributions from both electrons and protons, with protons playing the dominant role. Additionally, there are strong indications that particles diffuse in turbulence that has a Kolmogorov spectrum.