Interpretation of the results of the experiment on generation of parametric X-radiation by relativistic electrons in a single-crystal target

The coherent X-ray radiation generated by a relativistic electron beam in a monocrystalline target of a limited thickness is investigated in the framework of two-wave approximation of the dynamical theory of diffraction in the conditions of asymmetric reflection of the radiation waves in relation to the target surface. The calculations of the radiation angular density for the conditions of the recent experiment on generation of parametric X-ray radiation (PXR) have been carried out. It has been shown, that adequate description of such experiments is possible only with use of the dynamical theory which takes into account the effects of asymmetric reflection of the radiation.