POTENTIAL SCATTERING IN A STRONG MULTICOLOR LASER FIELD

Potential scattering in a strong elliptically polarized multicolour la ser field is considered. The first result is the off-shell low-frequen cy approximation for scattering with emission (absorption) of L photon s. A simple result for the total cross section is obtained using the o ptical theorem. In the case of a linearly polarized multicolour laser field a generalization of the on-shell Kroll-Watson-type low-frequency approximation is derived. Numerical results, obtained using the [1, 1 ] Pade approximant to the off-shell low-frequency T matrix for scatter ing on the Yukawa potential in a bichromatic laser field, are compared with the Varro and Ehlotzky results. The symmetry and asymmetry prope rties of the scattered electron spectra, as well as the symmetry break ing at higher laser field intensity, are analysed. It was observed tha t the differential cross section for scattering in a bichromatic laser field as a function of L. can have pronounced maxima. The positions o f these maxima are determined by the generalized Bessel function prope rties and can be controlled by changing the laser field intensity and the relative phase between the laser field components.