Particle production in a strong, slowly-varying magnetic field with an application to astrophysics

Abstract

In this work I studied the production of particles (electron-positron pairs and photons) in the presence of overcritic ($\gg 4.4\cdot 10^{13} \text{gauss}$) slowly varying magnetic fields. The calculations are performed in the framework of QED in the presence of external not quantized electromagnetic fields by means of the adiabatic perturbation theory. Also, since such strong magnetic fields may be present near astrophysical compact objects where gamma-ray bursts (GRB) are thought to be generated, I tried to reproduce theoretically some features of the GRB energy spectra such as the low energy ($\lesssim 0.1 \text{MeV}$) behaviour. Also, having in mind this astrophysical scenario, I took into account the effects of a weak and of a strong gravitational field on the production probabilities previously calculated in the flat Minkowski spacetime.