Effect of electron spin polarization in laser-assisted electron-proton scattering

TL;DR

This paper theoretically investigates how initial electron spin polarization influences electron-proton scattering in a circularly polarized laser field, deriving an analytic differential cross-section and examining the impact on electron polarization during scattering.

Contribution

It provides a new analytic expression for spin-dependent differential cross-sections in laser-assisted electron-proton scattering using Dirac-Volkov states and spin-helicity formalism.

Findings

Electron spin can be affected by the scattering process depending on kinetic energy.

The electromagnetic field influences the degree of electron polarization.

The work extends previous unpolarized scattering studies to include spin effects.

Abstract

This work aims to study theoretically the electron-proton scattering for initially spin-polarized electrons in the presence of a circularly polarized electromagnetic field. Using the first Born approximation and the Dirac-Volkov states for dressed electrons, we derive an analytic expression for the differential cross-section with the help of the spin-helicity formalism. Meanwhile, a well-known concept of spin-flip and spin non-flip differential cross sections is applied. The influence of the electromagnetic field on the degree of polarization of the scattered electron is investigated, and the effect of electron spin polarization is examined. We found that the initial spin of the electron can be affected depending on its kinetic energy during the scattering process. This work is a continuation of a recent paper in which we studied the unpolarized electron-proton scattering in the presence of a laser field (Dahiri, et al., Laser Phys. Lett. 18 (2021) 096001).