On the energy distribution of relativistic electrons in the young supernova remnant G1.9+0.3

TL;DR

This study analyzes X-ray data from the young supernova remnant G1.9+0.3 to understand the energy distribution of relativistic electrons, revealing slower-than-expected acceleration rates with implications for cosmic ray origins.

Contribution

It provides the first detailed electron energy distribution for G1.9+0.3 based on broad-band X-ray observations, highlighting slower acceleration than theoretical maximums.

Findings

Electron acceleration is an order of magnitude slower than Bohm limit.

X-ray emission is consistent with synchrotron origin.

Implications for the role of SNRs in Galactic Cosmic Rays.

Abstract

The broad-band X-ray observations of the youngest known galactic supernova remnant, G1.9+0.3, provide unique information about the particle acceleration at the early stages of evolution of supernova remnants. Based on the publicly available X-ray data obtained with the Chandra and NuSTAR satellites over two decades in energy, we derived the energy distribution of relativistic electrons under the assumption that detected X-rays are of entirely synchrotron origin. The acceleration of electrons was found to be an order of magnitude slower than the maximum rate provided by the shock acceleration in the nominal Bohm diffusion regime. We discuss the implications of this result in the context of contribution of SNRs to the Galactic Cosmic Rays at PeV energies.