On the creation of charged massless fermion pair by a photon in crossed electromagnetic field

TL;DR

This paper investigates the theoretical creation of charged massless fermion pairs by photons in a constant crossed electromagnetic field, extending quantum electrodynamics calculations to the massless limit and analyzing photon emission processes.

Contribution

It introduces a novel approach to calculate the probability of massless fermion pair creation and photon emission in external fields using the massless limit of existing scattering amplitudes.

Findings

Derived the total probability of massless fermion pair creation from photon scattering.

Calculated photon emission probability by charged massless fermions in the electromagnetic field.

Extended quantum electrodynamics results to the massless fermion case.

Abstract

Creation of charged massless fermion pair by a photon in external constant crossed electromagnetic field is considered. For this we use the expression of elastic scattering amplitude (EAS) of photon in the one-loop approximation of massive quantum electrodynamics obtained earlier and calculate its massless limit. We assume that the imaginary part of EAS of photon describes the total probability of charged massless fermion pair creation in external electromagnetic field. Photon emission by a charged massless fermion is also studied in constant crossed electromagnetic field. We obtain the total probability of photon emission calculating elastic scattering amplitude of charged massive fermion in the electromagnetic field in the massless limit.