Modeling of the spatially resolved nonthermal emission from the Vela Jr. supernova remnant

¹ DESY, 15738 Zeuthen, Germany
e-mail: iurii.sushch@desy.de
² Astronomical Observatory of Ivan Franko National University of L’viv, Vul. Kyryla i Methodia, 8, L’viv 79005, Ukraine
³ Institute of Physics and Astronomy, University of Potsdam, 14476 Potsdam, Germany

Received: 22 February 2018
Accepted: 24 July 2018

Abstract

Vela Jr. (RX J0852.0−4622) is one of just a few known supernova remnants (SNRs) with a resolved shell across the whole electromagnetic spectrum from radio to very-high-energy (>100 GeV; VHE) gamma-rays. Its proximity and large size allow for detailed spatially resolved observations of the source, making Vela Jr. one of the primary sources used for the study of particle acceleration and emission mechanisms in SNRs. High-resolution X-ray observations reveal a steepening of the spectrum toward the interior of the remnant. In this study we aim for a self-consistent radiation model of Vela Jr. which at the same time would explain the broadband emission from the source and its intensity distribution. We solve the full particle transport equation combined with the high-resolution one-dimensional (1D) hydrodynamic simulations (using Pluto code) and subsequently calculate the radiation from the remnant. The equations are solved in the test particle regime. We test two models for the magnetic field profile downstream of the shock: damped magnetic field, which accounts for the damping of strong magnetic turbulence downstream, and transported magnetic field. Neither of these scenarios can fully explain the observed radial dependence of the X-ray spectrum under spherical symmetry. We show, however, that the softening of the spectrum and the X-ray intensity profile can be explained under the assumption that the emission is enhanced within a cone.