Efficient electron heating in relativistic shocks and gamma ray burst afterglow

TL;DR

This paper proposes a mechanism for efficient electron heating in relativistic shocks, explaining gamma-ray burst afterglows through synchrotron emission from heated electrons in enhanced magnetic fields.

Contribution

It introduces a new understanding of electron energization via cross-shock potential in relativistic shocks, applicable to both magnetized and non-magnetized cases.

Findings

Electrons gain energy efficiently through cross-shock potential.

Synchrotron emission from heated electrons explains gamma-ray burst afterglows.

Mechanism applies to various shock magnetizations.

Abstract

Electrons in shocks are efficiently energized due to the cross-shock potential, which develops because of differential deflection of electrons and ions by the magnetic field in the shock front. The electron energization is necessarily accompanied by scattering and thermalization. The mechanism is efficient in both magnetized and non-magnetized relativistic electron-ion shocks. It is proposed that the synchrotron emission from the heated electrons in a layer of strongly enhanced magnetic field is responsible for gamma ray burst afterglows.