Relativistic magnetic reconnection in application to gamma-ray astrophysics

TL;DR

This paper investigates relativistic magnetic reconnection as a key particle acceleration process in gamma-ray astrophysical sources, using kinetic simulations to understand radiation variability and emission mechanisms.

Contribution

It provides new insights into particle acceleration and radiation processes in relativistically magnetized plasmas through detailed kinetic simulations.

Findings

Variability timescales can be shorter than the light-crossing time.

Simulations reveal detailed particle acceleration mechanisms.

Radiative energy losses are incorporated into the model.

Abstract

Cosmic sources of gamma-ray radiation in the GeV range are often characterized by violent variability, in particular this concerns blazars, gamma-ray bursts, and the pulsar wind nebula Crab. Such gamma-ray emission requires a very efficient particle acceleration mechanism. If the environment, in which such emission is produced, is relativistically magnetized (i.e., that magnetic energy density dominates even the rest-mass energy density of matter), then the most natural mechanism of energy dissipation and particle acceleration is relativistic magnetic reconnection. Basic research into this mechanism is performed by means of kinetic numerical simulations of various configurations of collisionless relativistic plasma with the use of the particle-in-cell algorithm. Such technique allows to investigate the details of particle acceleration mechanism, including radiative energy losses, and to calculate the temporal, spatial, spectral and angular distributions of synchrotron and inverse Compton radiation. The results of these simulations indicate that the effective variability time scale of the observed radiation can be much shorter than the light-crossing time scale of the simulated domain.