Emission of high-energy gamma quanta by ultrarelativistic electrons on nuclei in strong x-ray fields

TL;DR

This paper theoretically investigates how ultrarelativistic electrons interacting with nuclei in strong X-ray fields can produce high-energy gamma rays, potentially explaining gamma-ray emissions observed near pulsars and magnetars.

Contribution

It introduces a theoretical framework showing that resonant spontaneous bremsstrahlung in strong X-ray fields can generate gamma quanta with energies around 100 GeV, exceeding previous cross-section estimates.

Findings

Gamma quanta of ~100 GeV can be emitted in narrow cones.

Resonant differential cross-sections can surpass non-field cases by twenty orders of magnitude.

The process may explain high-energy gamma emissions from astrophysical objects.

Abstract

The possibility of radiation of high-energy gamma quanta with energies of the order of 100 GeV by ultrarelativistic electrons on nuclei in strong X-ray fields with intensities up to $\sim 10^{27}\ \text{Wcm}^{-2}$ has been theoretically studied. It is shown that this effect can be realized under special experimental conditions in the process of resonant spontaneous bremsstrahlung radiation of ultrarelativistic electrons on nuclei in an external electromagnetic field. These special experimental conditions determine the characteristic energy of the electrons. This characteristic energy should be significantly less than the energy of the initial electrons. Under these conditions, spontaneous gamma quanta are emitted in a narrow cone with energies close to the energy of the initial electrons. Moreover, the resonant differential cross-sections of such processes can exceed the corresponding differential cross-section without an external field by twenty orders of magnitude. The results obtained can explain the occurrence of high-energy gamma quanta near pulsars and magnetars.