Absorption cross section in an intense plane wave background
Abstract
We consider the absorption of probe photons by electrons in the presence of an intense, pulsed, background field. Our analysis reveals an interplay between regularisation and gauge invariance which distinguishes absorption from its crossing-symmetric processes, as well as a physical interpretation of absorption in terms of degenerate processes in the weak field limit. In the strong field limit we develop a locally constant field approximation (LCFA) for absorption which also exhibits new features. We benchmark the LCFA against exact analytical calculations and explore its regime of validity. Pulse shape effects are also investigated, as well as infra-red and collinear limits of the absorption process.
Cite
@article{arxiv.1907.12835,
title = {Absorption cross section in an intense plane wave background},
author = {Anton Ilderton and Ben King and Alexander John Macleod},
journal= {arXiv preprint arXiv:1907.12835},
year = {2019}
}
Comments
15 pages, 6 pdf figures. V2 updated to match published version