Finite time effects in single and double Compton scattering

TL;DR

This paper investigates how finite interaction times affect single and double Compton scattering, revealing observable effects at low energies and providing a method to regularize infrared divergences in the process.

Contribution

It introduces a modified fermion propagator to account for finite time effects in relativistic quantum electrodynamics, offering new insights and regularization techniques for Compton scattering.

Findings

Finite time effects are observable at low photon energies.

The method regularizes infrared divergences in double Compton scattering.

Potential experimental verification is discussed.

Abstract

The process of Compton scattering by a free electron with subsequent reemission of one or two photons is considered in the assumption of finite interaction time. The corresponding cross sections are obtained in the framework of relativistic quantum electrodynamics using a modified form of fermion propagator with complex transmitted momentum. It is shown that finite time effects can be observable at sufficiently low energies of scattered photons. The proposed method also regularizes arising infrared divergence in the cross section of the double Compton effect. Possible experimental verification of considered theoretical approach is discussed.