Polarization of recoil photon in nonlinear Compton process

Abstract

The polarization of recoil photon (\(\gamma '\)) in the nonlinear Compton process \(e + \vec L \rightarrow \vec {\gamma }' +e'\) in the interaction of a relativistic electron with a linearly polarized laser beam (\(\vec L\)) is studied within the Furry picture in the lowest order, tree-level S matrix element. In particular, we consider the asymmetry of differential cross sections \(\mathcal{A}\) for two independent axes describing the Compton process equal to the intrinsic spin variable \({\xi }^f_3\) that determines the polarization properties of \(\gamma '\). The sign and absolute value of the asymmetry determine the direction and degree of \(\gamma '\) polarization. We have analyzed the process in a wide range of laser intensity that covers existing and future experiments. Our results provide additional knowledge for studying nonlinear multi-photon effects in quantum electrodynamics and can be used in planning experiments at envisaged laser facilities.