Nonlinear resonance photoabsorption by metallic clusters in an intense laser field

A theoretical study of non-linear effects during the interaction of microscopic metallic clusters with the intense laser field is presented. The theoretical model, based on the separation of motion of the center of mass and internal excitations, is proposed. The mechanism of the resonance line shift in a nonlinear regime is investigated. The resonance photoabsorption cross sections and the angular distributions for the photoelectrons are calculated for various laser field intensities.