Free-free transitions in a bichromatic field of frequencies $ω$ and $2ω$ at moderate field intensities
Free-free transitions in laser-assisted electron-hydrogen scattering in a bichromatic field of frequencies $ω$ and $2ω$ are studied at moderate intensities for fast projectiles. A hybrid approach is used, in which the field-projectile interaction is described exactly but the field-target one is described by second order perturbation theory; the projectile-target interaction is treated in the first Born approximation. The adopted description of the target enables a consistent study of the leading process to each of the considered sidebands. Numerical results are presented for the angular distributions in a geometry and at frequencies for which the target dressing is important. The influence of the relative phase between the fields is investigated, too.