Parametric X-ray radiation in symmetric Bragg geometry

A detailed analysis of theoretical models used to interpret experiments with parametric X-ray radiation (PXR) emitted by relativistic charged particles in symmetric Bragg geometry is carried out. It is shown that the dynamical theory of PXR is in good agreement with the experimental results obtained at the Sirius synchrotron for 900 MeV electrons. The most important advantage of the PXR dynamical theory over the kinematical one is the correct description of the primary extinction and interference between two types of waves (fast and slow), generated within parametric X-ray radiation in a crystal. At ultrarelativistic energies, an analytical expression is obtained for the total number of quanta emitted by an electron into the solid angle where PXR intensity has a maximum.