Generation of Hard Bremsstrahlung at the Grazing Incidence of 18-MeV Electrons of a Betatron Beam on the Surface of Тa Foil 13 µm Thick

Abstract: The properties of the hard bremsstrahlung generated at the grazing incidence of 18-MeV electrons on the surface of a thin tantalum foil 13 μm thick and 2.5 mm long are studied using a facility based on the B‑18 betatron. The foil is placed in a goniometer inside the betatron chamber to obtain the orientation dependence of the generated radiation. A strong dependence of the angular distributions of hard bremsstrahlung on the orientation of a thin target is revealed, which is not observed at the normal incidence of electrons on its surface. Using the generated radiation, magnified images of the Duplex IQI reference and an object, consisting of thin layers of different materials, are obtained. The contribution of the absorption and edge phase contrasts to the formation of images of the wire structures of the reference and the planar interfaces in the complex object is studied. High-quality images of the objects are shown to be obtained due to the small horizontal size of the radiation source, which amounts to 13 μm for radiation emitted along the target and increases with growth in the angle of radiation emission.