The paper reports the results of the ion irradiation impact on a monocrystalline tungsten alloy, W‒6Re. This material is considered for use in the design of fusion reactors. Irradiation was carried out in order to simulate radiation effects and analyze the radiation resistance of the fusion reactor material. Specimens were irradiated with 5.6 MeV Fe ions at 500°C up to a maximum damage dose of 8 dpa. Microstructure of W–6Re was analyzed before and after irradiation. It is shown with transmission electron microscopy that the formation of structural defects, dislocation loops with sizes of 2–15 nm and a number density of 1.2 × 10²³ m⁻³ occurs as a result of irradiation. Detailed analysis by atomic probe tomography microscope revealed the decomposition of the solid solution with the formation of nanoscale segregations enriched in rhenium by 18 at %. The radiation-induced hardening of the irradiated layer is determined by nanoindentation. The strength increment was 1.6 GPa.

In a simple thermodynamic model, the transverse momentum distributions are found for -hyperons produced in pp collisions at ultrarelativistic energies. Studying the behavior of the average transverse momentum depending on the mass of the emitted particle shows that it is possible to search for large mass quark nuggets as possible candidates for the role of dark matter particles. An interpretation of the spectra of soft photons with respect to the transverse momentum in pp collisions is also given taking into account the boson X17, a new particle, a possible candidate for the role of dark matter particles.

This paper represents results of study of the AlCoCrFeNi high-entropy alloy by means of atom probe tomography. Two phases were found, one of which is enriched in Fe and Cr, and the other in Ni and Al. Due to the complex surface morphology and spatial configuration of the phases, their analysis was carried out by various statistical methods. The Fe−Cr phase has a honeycomb structure that contains Co particles with a size from 1 to 10 nm. Enrichment of the cell boundaries with Fe and Cr atoms reaches 50 at. %. In turn, the Al–Ni phase is enriched with each of these elements up to 30 at. % and contains nanoscale precipitates of Fe and Cr atoms. The number density of these clusters is ~6 ⋅ 10¹⁷ cm^–3.

An upgraded version of the combined optoacoustic gravitational radiation detector OGRAN is considered. This underground setup located at the Baksan Neutrino Observatory is designed to search for collapsing stars in the Galaxy in conjunction with the neutrino telescope BUST. Both instruments possess the sensitivity sufficient for registering collapses in our Galaxy as rare events with an average rate of 0.03 events per year. Observations are carried out in the form of continuous synchronous monitoring of the astrophysical background through both recording channels. Strict requirements are imposed on the systems for maintaining the operating modes of both installations. For the gravity detector, the problem is nontrivial owing to the complexity of its utomatic control systems and fine-tuning of the operating point. For this reason, the method and technique for maintaining the OGRAN detector in monitoring mode is described in detail. Also, the characteristics of the OGRAN detector after modernization are briefly presented.

The determination of the centrality of the collision or the magnitude of the impact parameter of the collision of heavy nuclei is of great importance for the analysis of all experimental data and comparison with theory. One method is to measure the number of spectators using a hadron calorimeter located at a small angle to the nuclear beam. It was shown that with an achievable energy resolution of the hadron calorimeter, the accuracy of determining the collision parameter is insufficient for using the calorimeter in the MPD/NICA and CBM/FAIR projects. The error reaches 35% at a beam energy of 2.5 GeV, even for peripheral collisions. Secondary processes during the passage of spectators through the nucleus give an additional contribution to the error for central collisions and at medium centralities.

This article discusses modernization of the HIPr accelerator for irradiation of tungsten samples with a 10 × 10 mm form factor aimed at simulating radiation induced defects. The measurement system of the beam current is developed for experiments on target irradiation. The simulation results of beam transport in the accelerator output channel are presented with the measurements of beam transversal profiles and currentin the samples.

The results of mechanical and electrodynamic calculations of a frequency tuner for the half-wave superconducting resonator operating at 325 MHz and a relative speed of 0.21 for the Nuclotron-NICA megascience injection facility are presented. The tuner compensates for the resonance frequency drift caused by external factors. Methods for tuning the frequency of half-wave resonators are considered, the method most suitable for the conditions of the project is selected, and the design of a frequency tuner is developed.

₂₃₈U⁶⁰⁺ ion beam dynamics simulations results in a lattice that turns particles at 180 degrees and located between two LINAC-100 superconducting sections of DERICA project (JINR, Dubna, Russia) for studying radioactive isotopes are presented. Lattice layout is proposed. Parameters of its optic element are chosen so that dispersion function has zero value at the entrance and exit of the channel for transporting the 50 MeV/nucleon ion beam.