Coulomb final state interaction in cascade Auger processes

A post-collision interaction (PCI) in the cascade Auger processes is considered. The general analytical formulae for an amplitude and a cross section of the process under consideration are obtained. These formulae allow for the PCI distortion and are valid for a wide range of velocities of the emitted electrons except a near-threshold region. A structure on the photoelectron line profile is revealed for some kinematics of the reaction. This structure is associated with the electrons interaction following the cascade Auger decay, rather than an interference between the amplitudes for the resonance and non-resonance processes. (author)