Abstract: | X-ray ion radiation, caused by resonant coherent excitation (RCE) in a crystal, arises at the crystal-vacuum interface and propagates along the surface, generating a so-called surface wave. The dependence between the surface-wave intensity and the departure angle of characteristic X-ray radiation upon RCE is investigated in a kinematic approximation of diffraction theory. It has been shown that the angular dependence for the intensity of this radiation leaving the crystal surface differs substantially from the radiation intensity inherent to the decay of ion states excited by RCE. |