Experimental comparison of parametric X-ray radiation and diffracted bremsstrahlung in a pyrolytic graphite crystal

Spectral characteristics of diffracted bremsstrahlung (DB) and parametric X-ray radiation (PXR), that can be treated as a diffraction of the own field of a charged particle moving through a crystal, were measured under similar experimental conditions. The target used was a pyrolytic graphite crystal with a mosaic factor of approximately 3 mrad. It is shown that for the thickness of a mosaic graphite target approximately 0.01 rad length and ω≥γω-p$/, the contribution from diffraction of real photons into spectrum measured is comparable with that from PXR. For DB, the yield ratio falls well within the diffraction theory of X-rays in mosaic crystals, taking into account the effect of suppression of bremsstrahlung. For PXR, the yield ratio may be satisfactory explained following the kinematic theory, taking into account the PXR photon diffraction and correlation between DB and PXR intensity.