Electron-atom scattering in a laser field

The authors studied the dressed effects of atom for multiphoton Free-Free transition in this paper. In the work, atom can exchange any number of photon with a laser field or a free electron, but in the work of Joachain et al only single photon is exchanged. Taking hydrogen as an example, the authors finished detailed calculatons and analysed the changes of differential cross section with the energy of photon and with the angle of scattering, which shows that when the laser field is stronger, the dressed effects of atom are significant, and particularly important in the region of small momentum transfers. In contrast to the results of Joachain et al, the dressed effects of atom based on the results obtained are also significant even net number of exchanged photon is zero. The authors also find that the dressed effects of atom can led intensification of oscillation in the cross sections of Free-Free transition with angle or photon energy