Probabilistic Model of the Scattering of Ultrashort Pulses on a Free Electron

This study is devoted to generalization of the traditional approach for the description of photon scattering on free electrons in the case of ultrashort laser pulses. In the framework of the second order of quantum mechanical perturbation theory with the use of the Klein–Nishina formula, we derived an expression for the total scattering probability during the whole time of the pulse action that is applicable in the relativistic limit. The redshift of scattered pulse spectra under an increase in the scattering angle in the relativistic case was studied. The trends of the total scattering probability on the duration of ultrashort laser pulses were categorized.