Abstract
A pyroelectric X-ray source is proposed, in which a lithium tantalate crystal is heated by an infrared laser with a wavelength of 10.6 μm. X-ray spectra measured during irradiation of the ...crystal with infrared radiation and during natural cooling of the crystal include characteristic X-ray radiation of atoms contained in the structural parts of the source, as well as bremsstrahlung of electrons with energies above 50 keV. An 8 mm sodium chloride window was used to inject 64 W infrared radiation into a vacuum chamber with the pyroelectric crystal installed.
The paper describes a nondestructive testing method for the study of structural elements made of lightweight materials. The method is based on the analysis of soft X-ray spectra. The test results for ...a pipe made of carbon fiber with an average wall thickness of 1 mm are presented. The possibility of constructing maps of the distribution of pipe wall thickness with an accuracy above 10 μm is shown.
Description of modern pyroelectric technologies is presented in this article. Various schemes for generating X-ray radiation are presented. The possibility of controlling charged particle beams by ...means of a pyroelectric deflector is demonstrated. The prospects for the development of pyroelectric technologies and their application are discussed.
Optical Cherenkov radiation of moderately relativistic ions in a CVD-diamond plate with frequency dispersion is considered. It has been shown that Cherenkov radiation extracted from the inclined ...diamond plate to vacuum at a fixed observation angle becomes monochromatic. The wavelength of the spectral line depends on the energy of an ion and on the geometry of an experiment (observation angle and plate inclination angle). An experiment has been proposed to study the monochromatization of Cherenkov radiation on the beam of the JINR Nuclotron for the purpose of its subsequent use in the diagnostics of ion beams. The method can be applied to monitor the NICA ion beams energy.
The possibility of neutron generation by irradiating deuterated crystalline structures with an electron beam with an energy of 20–40 keV was studied. As targets, the deuterated crystalline structures ...of palladium and textured CVD diamond were used. Measurements of neutron emission are presented, which were carried out by three independent methods—scintillation detectors, counters based on He-3, and track detectors CR-39.The average neutron flux during irradiation was estimated as 1–10 s
in 4
sr.
The solution of the problem how to register fast neutrons in the presence of intense gamma radiation is required when solving such fundamental and applied problems as registration of the neutron and ...gamma background in underground low-background experiments (the low background detectors of the neutrino and dark matter); beam diagnostic at particle accelerators; radiation monitoring at nuclear facilities, nuclear medicine; environmental monitoring. To separate signals from neutrons and gamma quanta, scintillation detectors with organic scintillators are used. The best scintillators are organic crystals of stilbene and p-terphenyl. The efficiency of separating signals from neutrons and gamma quanta can be increased using various methods of digital signal processing of the pulse shapes of the registered signals. A parameter traditionally called the Figure of Merit (FOM) is used to compare these methods. The experimental setup consisted of a Pu-Be neutron source, a scintillation detector with organic crystal p-terphenyl, a Hamamatsu R6094 photomultiplier, a CAEN DT5730 Digitizer (500 MHz, 14bit), which store the shape of each pulse for the following digital processing. A new "method of normalized signals" was developed. Three variants of the new method of normalized signals are described, which give the following FOM values: 1.6, 1.7, and 2.1. The traditional method of signals separation on the same array of experimental data showed the efficiency FOM = 1.6. The new method of signal separation is used to register fast neutrons in the installation dedicated for the development of a compact neutron generator, which is necessary for the calibration of low-background detectors of neutrinos and dark matter particles.
The NICA accelerator complex includes beam transfer lines and stations for applied research. The first commissioning of the Station of Chip Irradiation (SOCHI) was performed at the end of 2021with С
...4+
heavy ions extracted from the linear accelerator (HILAC) at an energy of 3.2 MeV/n. The new SOCHI beam transfer line is integrated in the existing HILAC-Booster beamline. The Irradiation Setup for Components of Radioelectronic Apparatus (ISCRA) with ion energy ranging from 150 to 500 MeV/n and the Setup for Investigation of Medical Biological Objects (SIMBO) with the ion energy ranging from 400 to1100 MeV/n are based on the beams extracted from Nuclotron. The equipment of ISCRA and SIMBO stations has been manufactured and is planned to mount in the end of 2022. The beamlines are being designed now. The technical parameters of the beamlines and stations and the results of the first run of the SOCHI station are presented in this study.
The paper presents the results of an experiment on the generation of parametric X-ray radiation (PXR) in the interaction of relativistic electrons with highly oriented pyrolytic graphite. ...The measurements are performed at an observation angle of 180° relative to the electron velocity. For the first time, the spectrum of parametric X-ray radiation formed in highly oriented pyrolytic graphite in the backscattering geometry was recorded. The dependences of the radiation output on the orientation angle of the irradiated target are measured.
We study the conductivity and magnetoresistance of the α‴ phase solid solution of (Cd1−xZnx)3As2 (x = 0.45). Single crystals of (Cd1−xZnx)3As2 are obtained by the modified Bridgman method. The space ...group and tetragonal lattice parameters of single crystals are found to be I41/amd and a = b = 8.56(5) Å, c = 24.16(6) Å. The temperature dependence of the conductivity and magnetoresistance is studied in the temperature range of 1.6–320 K and in the presence of a transverse magnetic field from 0 to 10 T. Mixed conductivity is analyzed using Hall resistivity data and standard quantitative mobility spectrum analysis. The concentration and mobility of holes are determined at different temperatures. The presence of two types of holes with different mobilities is demonstrated in the temperature range of 1.6–19 K, while with increasing temperature, just one type of charge carrier is observed in the mobility spectrum.
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