Anomaly in the Interaction between Microfocus Bremsstrahlung from a New 18 MeV Betatron-Based Source and a Sharp Edge of a Steel Plate

Images of the distribution of microfocus bremsstrahlung from a new source based on an 18 MeV betatron, which has passed a 0.4 mm thick steel plate with a 1.2 mm wide sharp edge, are presented. The photographs demonstrate an anomaly in the interaction between the microfocus bremsstrahlung and the plate tip in the form of a narrow dark stripe along the tip image, which indicates an increase in the radiation intensity in this area. The dark stripe provides a contrast in the tip image, which, together with the high sharpness due to the microfocus of the source, allows the tip position to be visualized with high precision. The dark stripe in the images was not observed when using radiation from 450 and 45 keV X-ray tubes with foci of 400 and 100 μm. The absorption of radiation ensures a smooth change in the blackening of the sharp edge and blurring of the tip in the image due to the size of the radiation source. The observed effect with microfocus radiation of the new source is determined by the scattering of radiation by the tip with the possible participation of wave effects, which needs to be further investigated.

microfocus bremsstrahlung, edge absorption and phase contrasts, radiation refraction