Parametric x-radiation from mosaic graphite: new results and reconciliation of previous experiments

Abstract

This thesis explores the effects of mosaic graphite on the yield of parametric x-radiation (PXR). PXR is the Bragg scattering of virtual photons associated with the Coulombic field of relativistically charged particles interacting with the atomic planes of a crystal. PXR was measured from three samples of mosaic graphite crystals with differing mosaicities. The number of photons per electron was calibrated with the fluorescent x-ray yield from a thin silver foil backing on each of the mosaic crystals. The detector angular field of view was narrowed from previous experiments. Improvements were made in the re-analysis of previous experiments by considering the thick target effects of the x-ray absorption. Previous experiments had erroneously assumed that the calibration fluorescent targets were thin. Re-analysis of previous data using corrections for solid angle, crystal absorption factors and effective thickness resulted in yields similar to those obtained in this work.