Linear microfocus bremsstrahlung generated in light and heavy narrow targets in B-18 betatron

Abstract

The first results of studying the properties of X- and G-ray beams generated at the grazing incidence of 18-MeV electrons with the 50 and 8-[mu]m-thick Si crystals and a 13-[mu]m-thick Ta foil of 4 mm in length along the electron beam are presented. The target has been placed in a goniometer inside the chamber of a B-18 betatron. The results exhibit strong changes in the angular distribution of radiation at the variation of the orientation of the target. This effect is not observed in the case of the normal incidence of electrons on the surface of a thin target. Images of a reference microstructure have been obtained with a high resolution of details of the microstructure owing to the smallness of the source of radiation. The dependence of the contrast of an image on the position of the microstructure in the radiation cone has been demonstrated, which is determined by the change in the effective size of the radiation source when the emission angle of the source is changed