Analytical Infrared Limit of Nonlinear Thomson Scattering Including Radiation Reaction

TL;DR

This paper derives an analytical expression for the infrared limit of nonlinear Thomson scattering that incorporates radiation reaction effects, revealing significant qualitative and quantitative modifications to the emitted radiation spectrum in intense electromagnetic fields.

Contribution

It provides the first analytical formula including radiation reaction effects for the infrared behavior of nonlinear Thomson scattering in arbitrary plane waves.

Findings

Radiation reaction significantly alters the infrared spectrum.

The analytical expression applies to arbitrary plane waves.

Results serve as a classical signature of radiation reaction and inform strong-field QED.

Abstract

If an electric charge is accelerated by a sufficiently intense electromagnetic field, the effects of the radiation emitted by the charge on the charge dynamics (radiation reaction) cannot be ignored. Here we show that classical radiation-reaction effects alter qualitatively and quantitatively the infrared behavior of the spectrum of the radiation emitted by an electron in the presence of an intense electromagnetic plane wave (nonlinear Thomson scattering). An analytical expression of the infrared limit of nonlinear Thomson scattering is provided, which includes radiation-reaction effects and is valid for an arbitrary plane wave. Apart from their own conceptual importance and as a signature of classical radiation reaction, these results provide the limiting expression of the corresponding and yet unknown exact infrared behavior of strong-field QED in an intense plane wave.