Investigating the one-photon annihilation channel in an e-e+ plasma created from vacuum in strong laser fields

TL;DR

This paper investigates the one-photon annihilation process in an electron-positron plasma created from vacuum by strong laser fields, focusing on regimes accessible to upcoming high-intensity X-ray laser experiments.

Contribution

It extends previous kinetic models to estimate photon annihilation radiation in the gamma < 1 regime, relevant for next-generation X-ray laser experiments.

Findings

Photon annihilation radiation could be experimentally observable in high-intensity X-ray laser setups.

The effective mass model predicts significant radiation intensity in the gamma < 1 regime.

The study bridges theoretical predictions with potential experimental detection in strong-field QED.

Abstract

It is well known that in the presence of strong external electromagnetic fields many processes forbidden in standard QED become possible. One example is the one-photon annihilation process considered recently by the present authors in the framework of a kinetic approach to the quasiparticle e-e+ gamma plasma created from vacuum in the focal spot of two counter-propagating laser beams. In these works the domain of large values of the adiabaticity parameter gamma >> 1 (corresponding to multiphoton processes) was considered. In the present work we estimate the intensity of the radiation stemming from photon annihilation in the framework of the effective mass model where gamma < 1, corresponding to large electric fields E < E_c=m^2/e and high laser field frequencies (the domain characteristic for X-ray lasers of the next generation). Under such limiting conditions the resulting effect is sufficiently large to be accessible to experimental observation.