Electron-atom scattering in a circularly polarized laser field - art. no. 063417

We consider electron-atom scattering in a circularly polarized laser field at sufficiently high electron energies, permitting us to describe the scatt ering process by a first-order Born approximation. Assuming the radiation f ield has sufficiently moderate intensities, the laser dressing of the hydro gen target atom in its ground state will be treated in second-order perturb ation theory. Within this approximation scheme, it is shown that the nonlin ear differential cross sections of free-free transitions do not depend on t he dynamical phase phi of the radiative process nor on the helicity of the circularly polarized laser light. Relations to the corresponding results fo r linear laser polarization are established.