Bremsstrahlung photon polarization for ee± → (eγ)e± and ep → (eγ)p high-energy collisions

The polarization of a bremsstrahlung photon during the processes ee± → (eγ)e± and ep → (eγ)p is calculated for peripheral kinematics in the high-energy limit, where the cross section does not decrease with the incident energy. When the initial electron is unpolarized (longitudinally polarized), the final photon can be linearly (circularly) polarized. The Stokes parameters of the photon polarization are calculated as a function of the kinematical variables of the process: the energy of the recoil particle, the energy fraction of the scattered electron, and the polar and azimuthal angles of the photon. The numerical results are given in the form of tables for typical values of the relevant kinematic variables.