Trident pair production in plane waves: Coherence, exchange, and spacetime inhomogeneity

TL;DR

This paper provides a comprehensive analytical and numerical study of the trident process in inhomogeneous plane wave backgrounds, highlighting the roles of exchange, coherence, and spacetime inhomogeneity in quantum electrodynamics.

Contribution

It derives compact analytical expressions for all terms in the trident probability in arbitrary plane waves, including exchange effects, and evaluates these numerically with new techniques.

Findings

Exchange effects significantly influence the total probability.

The one-step process can dominate under certain conditions.

Results clarify the validity of the locally constant field approximation.

Abstract

We study the trident process in inhomogeneous plane wave background fields. We obtain compact analytical expressions for all terms in the probability, including the exchange part, for an arbitrarily shaped plane wave. We evaluate the probability numerically using complex deformation of lightfront time integrals and derive various analytical approximations. Our results provide insights into the importance of the one-step and exchange parts of the probability relative to the two-step process, and into the convergence to the locally constant field approximation.