Radiation and electronic transitions in atom interaction with ultrashort impulse of electromagnetic field

The electron transitions and atom radiation by its interaction with the spatially nonhomogeneous ultrashort pulse of the electromagnetic field are considered; the excitation and ionization probabilities as well as the spectra and cross-sections of the overradiation by such an atom are obtained. The single-electron and two-electron inelastic processes accompanying the interaction of the ultrashort pulses with the hydrogenic and helium-like atoms are considered as an example. The developed methodology makes it possible to take into account the spatial nonuniformity of the ultrashort pulse and the photon pulses in the overradiation processes