Multi-photon enhancement of the Schwinger pair production mechanism under strong FEL radiation

TL;DR

This paper investigates how stochastic amplitude fluctuations in counter-propagating FEL beams can significantly enhance multi-photon Schwinger pair production, extending previous standing wave models.

Contribution

It introduces a model incorporating stochastic amplitude fluctuations of FEL beams, revealing substantial non-linear enhancement in pair production over a wide intensity range.

Findings

Large non-linear enhancement in pair production due to amplitude fluctuations

Enhancement depends on the order of the multi-photon process

Implications for future ultra-strong FEL radiation experiments

Abstract

In this work we study the production of electron-positron pairs from vacuum in presence of a field resulting from the collision of two counter-propagating FEL beams that undergo Gaussian amplitude fluctuations. Our work aims to the extension of previous works based on the standing wave hypothesis, by including the inherent stochastic amplitude fluctuations of the individual FEL beams. As shown, depending on the order of the process, a large non-linear enhancement in the number of created pairs can be expected over a big intensity window in the multi-photon regime. Vacuum pair creation in view of future plans on the production of ultra-strong and high energy radiation in FEL facilities is also discussed.