Energy Partition between Energetic Electrons and Turbulent Magnetic Field in Supernova Remnant RX J1713.7-3946

TL;DR

This paper investigates the energy distribution in supernova remnant RX J1713.7-3946, providing observational evidence for energy equipartition between energetic electrons and magnetic fields through simulations and spectral analysis.

Contribution

It presents the first observational evidence of energy equipartition between electrons and magnetic fields in a supernova remnant using spectral modeling and MHD simulations.

Findings

Electron energy density is proportional to magnetic field energy density.

Total energy of electrons above 1 GeV equals magnetic field energy.

Supports leptonic scenario for gamma-ray emission in SNR RX J1713.7-3946.

Abstract

Current observations of supernova remnant (SNR) RX J1713.7-3946 favor the leptonic scenario for the TeV emission, where the radio to X-ray emission is produced via the synchrotron process and the $\gamma$-ray emission is produced via the inverse Comptonization of soft background photons, and the electron distribution can be inferred from the observed $\gamma$-ray spectrum with a spectral inversion method. It is shown that the observed correlation between the X-ray and $\gamma$-ray brightness of SNR RX J1713.7-3946 can be readily explained with the assumption that the energy density of energetic electrons is proportional to that of the magnetic field in such a scenario. A 2D magnetohydrodynamic simulation is then carried out to model the overall emission spectrum. It is found that the total energy of electrons above $\sim 1$ GeV is equal to that of the magnetic field. This is the first piece of observational evidence for energy equipartition between energetic electrons and magnetic field in the downstream of strong collision-less astrophysical shocks of SNRs.