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The formation region effects in x-ray transition radiation have been experimentally investigated. The radiation was generated using 1–6 GeV electrons impinging on two multilayer targets with considerably different periods. The absolute yield of transition radiation was measured and the wide spectral peak in the range from 10 to 30 keV was observed. In the most part of the electron energy range the emission from the short-period radiator was expectedly suppressed, compared to the case of the long-period one. But for the electron energy of 1 GeV an opposite effect, though rather small, of the emission enhancement in the short-period radiator was observed. The conditions, under which this effect is much stronger, are derived and its possible practical value is outlined. The theory accounting for an arbitrary transversal shape of the electron beam and the finite size of the detector is developed. This theory describes rather well the experimental results.

The possibility of the measurement of proton ionization loss in the Silicon (Si) layer of smoothly tunable thickness was demonstrated in an experiment with a 50-GeV proton beam. The Si surface-barrier detector with the depleted layer thickness controlled by the value of high-voltage power supply was used in the experiment. The measured spectra of ionization loss are discussed and compared with the calculated spectra. The possibilities of research of the evolution of electromagnetic field of ultrarelativistic particles traversing the media interface and the study of dynamics of particles moving in the channeling regime or the volume reflection regime with the use of detectors with smoothly tunable thickness are indicated.

The possibility of measurement of electrons ionization loss in Si layer of smoothly tunable thickness is shown in the proof-of-principle experiment. The Si surface-barrier detector with the depleted layer thickness controlled by the value of high voltage power supply has been used. Ionization loss spectra for electrons emitted by radioactive source 207Bi are presented and discussed. Experimental results for the most probable ionization loss in the Landau spectral peak are compared with theoretical calculations. The possibility of research of evolution of electromagnetic field of ultra-relativistic particles traversing media interface with the use of detectors with smoothly tunable thickness is proposed.

The results of the experimental observation of characteristic X-ray radiation (CXR) excited in solid targets by the extracted and circulated 450 MeV/u C+6 ions beams and circulating 1.3 GeV protons beam are presented. The spectra of X-ray radiation measured from different targets are presented and discussed. It was found that the background radiation near the beams is low enough that allows the observation of the CXR spectral peaks with energies from a few to tens keV by semiconductor X-ray detectors. Applications of the CXR for monitoring of the number of accelerated particles in experimental applied and basic research, including radiobiology and radiation medicine as well as the relativistic nuclear physics and steering of beams by bent crystalline deflectors are proposed.

A set of experiments to study the guiding of 10 keV electrons by tapered glass capillaries was performed. It is shown that the 10 keV electron beam can be tightly focused by the tapered macrocapillaries. The charge/discharge processes of the capillary inlet are shown and discussed. The guiding effect was obtained for 10 keV electrons by a tapered glass capillary of a simple shape. The electron beam transmission was measured for several angles.

For the first time a classical model was developed to describe quantitatively the dynamics of charge distribution formation on a planar dielectric surface during its irradiation by fast electrons at a grazing incidence. The dynamic effects of the mutual influence of the beam and the dielectric surface charge predicted by the developed model are in a good agreement with the performed experiments. The proposed model can be used to describe time dependent processes of the electron beam–dielectric surface interaction, charging up and discharging for dielectric channels of more complex shapes.

The collimated spectra of polarization bremsstrahlung (PB) produced by 7 MeV electrons in Al, Ni, Cu, Mo and W poly crystalline foils are measured and the angular dependences of the PB characteristics are studied. A comparison of the experimental results with theoretical predictions is performed. Polarization bremsstrahlung sensitivity to texture and grain size of the target in the backscattering geometry is shown. The possibility of developing a new method based on the characteristics measurement of the coherent PB component for the diagnostics of polycrystalline materials is considered.