Hydrides’ reorientation is one of the most critical mechanisms observed during dry storage of spent fuel, which can cause depressurization of the fuel element cladding. In this work hydrides reorientation of unirradiated gas pressurized samples made from VVER-1000 cladding material (Zr‒1% Nb) has been investigated under conditions simulating long-term dry storage. Thermomechanical tests were conducted with samples containing 100 and 200 ppm of H according to different annealing scenarios with cladding hoop stresses up to 100 MPa. It was revealed that hydrides reorientation and induced plasticity decrease of the cladding material were not significant. Hoop stress level appeared to be the most significant factor that affects hydrides reorientation in the cladding.

A scheme of the end-to-end polynomial interpolation of the chord and radial functions using Chebychev polynomials is presented. Formulas for the first seven polynomials for both functions convenient for developing numerical codes are displayed.

Investigation of instabilities that emerge in the interaction of a charged-particle beam with elements of the chamber of state-of-the-art synchrotron radiation sources and colliders is an important task, since the beam parameters required in such facilities can only be attained if such effects are taken into account. Conditions for the development of a microwave instability in the USSR, a fourth-generation 6-GeV synchrotron radiation source with an emittance of 70 pm under design, are analyzed. The options to reduce its effect on the parameters of the beam accumulated in the accelerator ring and, as a result, on the output parameters of the facility are investigated.

The paper presents the research results of biperiodic accelerating structure with internal coupling cells for the linear accelerator proposed as an injector for 4th generation synchrotron radiation source SILA. The issues of accelerating field in accelerating structure limitation caused by surface electric and magnetic fields for S, C and X band operated cavities are considered.

Methods of increasing the critical energy for the proton option of the NICA collider are investigated. The method of superperiodic modulation of quadrupole gradients is applied. The selection of sextupoles is carried out to suppress the natural chromaticity and compensate for the sextupole component. The Twiss parameters for the proposed structures are given, as well as the dynamic apertures and working points are investigated.

Two options for damping HOM using rectangular waveguides and corrugated cylindrical waveguides were considered. Tuning, calculation of the electrodynamic characterisitcs (EDC) of the two structures was conducted.

A system for creating a toroidal magnetic field in the MEPHIST tokamak is described. The system is a single toroidal solenoid consisting of 12 copper loops made from a copper strip of variable width. The shape of the poloidal cross section is selected based on the zero torque condition. The distribution of the angle of inclination of the loops in the toroidal direction along their length was selected empirically by means of numerical modeling designed to minimize the scattered fields. The expected corrugation of the magnetic field at the large radius of the tokamak is ~0.6%. The inductance of the solenoid and the current supply lines is ~ 37 mH, the ohmic resistance is ~12 mW. When the toroidal field was raised, the loop voltage of ~ 3 V was observed.

Radioactive isotopes have been until now one of the most frequently used sources of gamma radiation. A broad usage of these sources is explained by their compactness, low price, and clean energy spectrum of radiation. Nevertheless, the modern trend set by the IAEA is to find technologies alternative to such sources owing to the hazard of emergencies, leakage, or illegal usage. Bremsstrahlung generated by electron accelerators can be used for replacement of radioactive sources. However, to efficiently compete with radioisotope sources, accelerators should feature comparable weight, dimensions, and cost. This work presents an accelerator developed by RadiaBeam to replace such radioactive isotopes as Co-60.

This paper considers the power supply scheme of a hybrid accelerator with standing and traveling wave sections, connected through a ferrite circulator from an autogenerator. Parameters of the accelerating sections and the cell parameter change sensitivity characteristics are determined for the accelerator with output beam energy 10 MeV and beam current 300 mA. Autogenerator stabilization issues are considered.

We have investigated the robustness of the spin-navigator based method for manipulating the beam polarization to bend magnet installation errors. Toward that end, variation of the invariant spin axis components along the beamline of an imperfect storage ring operating in the spin-transparent mode has been estimated. The beam polarization vector behavior in the given lattice has been investigated. Conclusions are made regarding the feasibility of using “spin navigator” solenoids for defining the beam polarization axis in the detector region.

The formation of ion fluxes of the laser plasma by axially symmetric magnetic field is studied. An algorithm for forming ion fluxes is developed and a computer experiment is carried out. As a result of the computer and physical experiments, it is shown that ion packets with a duration exceeding several microseconds, which contain more than ~ 10¹² particles at a flight distance of about 2 m, can be obtained at the output of a laser–plasma ion source.

Emission of short electron bunches with high charge in RF guns is considered. The emission mechanism in the case of picosecond laser pulses and the presence of a strong electric field at the cathode is quite different from the traditional one limited by the space charge of emitted particles. In this case, it is necessary to take into account the influence of positive charge dynamically formed on the cathode surface related to the difference of velocities of photoelectrons leaving the semiconductor film of the photocathode and velocities of electrons entering the emission region. The comparison of the numerical results and experimental data obtained at the facility for testing photoinjectors at PITZ (DESY, Zeuthen, Germany) demonstrated good agreement.

A terahertz NH₃ laser optically pumped by a “long” (~100 μs) pulse of an electron-beam-controlled discharge CO₂ laser was for the first time launched, the NH₃- and CO₂ laser pulses being simultaneously measured with nanosecond resolution. The NH₃ laser pulse duration and its lasing delay relative to the pump pulse beginning were measured versus the CO₂ laser pulse energy. The terahertz emission wavelengths of the NH₃ laser pumped by 9R(30) CO₂ laser line were identified – 67.2, 83.8, and 88.9 μm.

The processes of thin film electrochromic modules degradation during their cycling through the formation of blisters within the PVD sputtered tungsten oxide electrode layers are considered. The formation of blisters is shown to be caused by the retention of radical components transported into the tungsten films from the underneath layers of the module’s layerstack. Permeability of the ceramic tungsten-oxide layers of varying stoichiometry is studied by the means of thermal desorption spectroscopy and the ways for increasing the cycling sustainability of tungsten layers through their reactive magnetron PVD in deficiency of reactive component of working gas mixture are proposed.

In this work, we experimentally study intracavity frequency conversion of CO laser radiation in a nonlinear ZnGeP₂ crystal under noncritical phase matching. Various configurations of a laser cavity are considered, in one of which the nonlinear crystal itself was an output mirror. The spectrum of the converted radiation was shifted into the short-wavelength region due to the temperature tuning of the phase matching in the nonlinear crystal. The maximum average lasing power was obtained at room crystal temperature and an output mirror with a transmission T ~ 10% for the fundamental band, and reached ~7.0 mW. The power ratio of sum frequency generation and the CO laser radiation was ~16%, which turned out to be higher than the value obtained earlier with the BaGa₂GeSe₆ crystal (11.5%) at the same laser facility.

The authors within the Higgs Boson Working Group of the ATLAS experiment at the LHC performed an analysis of events with two leptons and two hadron jets to study Standard Model Higgs boson properties in the H→WW*→ℓνℓν decay channel in the vector boson fusion production mechanism. The analysis was based on full statistics of proton-proton interactions taken during 2015–2018 year exposures at √s=13 TeV. For the final state with one electron and one muon the study is completed. The observed and expected statistical significances of the signal were calculated without taking into account systematic uncertainties. An investigation of final states with two electrons and two muons and at least two hadronic jets has been started. Signal selection criteria are proposed and a strategy to subtract the main background from Drell–Yan processes was chosen. It is shown that experimental kinematical distributions are reproduced by the MC simulations.