On the Jitter Radiation

TL;DR

This paper investigates jitter radiation in turbulent astrophysical environments, deriving a new spectral power expression that highlights its potential to produce high-energy gamma rays, possibly dominating other mechanisms.

Contribution

It introduces a novel perturbation theory approach to analyze jitter radiation spectral properties, providing a compact formula suitable for numerical analysis.

Findings

Derived a general spectral power expression for jitter radiation.

Showed jitter radiation can produce high-energy gamma rays efficiently.

Highlighted conditions where jitter may dominate over synchrotron emission.

Abstract

In a small scale turbulent medium, when the nonrelativistic Larmor radius $R_{\rm L}=mc^2/eB$ exceeds the correlation length $\lambda$ of the magnetic field, the magnetic bremsstrahlung of charged relativistic particles unavoidably proceeds in the so-called jitter radiation regime. The cooling timescale of parent particles is identical to the synchrotron cooling time, thus this radiation regime can be produced with very high efficiency in different astrophysical sources characterized by high turbulence. The jitter radiation has distinct spectral features shifted, compared to synchrotron radiation, towards high energies. This makes the jitter mechanism an attractive broad-band gamma-ray production channel which in highly magnetized and turbulent environments can compete or even dominate over other high energy radiation mechanisms. In this paper we present a novel study on spectral properties of the jitter radiation performed within the framework of perturbation theory. The derived general expression for the spectral power of radiation is presented in a compact and convenient for numerical calculations form.