Table of contents

Abstract

• Photonics, quantum metrology, optical information processing;

• Ultrahigh optical fields, high-power lasers, Mega Science facilities;

• Spectroscopic synchrotron, neutron, laser research methods, quantum mechanical calculation and computer modelling of condensed media and nanostructures;

• High energy density laser physics.

More than 300 specialists took part in the Conference. They represented leading Russian scientific research centers and universities (National Research Centre "Kurchatov Institute", P.N. Lebedev Physical Institute, A.M. Prokhorov General Physics Institute, Joint Institute for Nuclear Research, Moscow Institute of Physics and Tecnology and others) and leading scientific centers and universities from Germany, Italy, France, Canada, Japan. We would like to thank heartily all of the speakers, participants, organizing and program committee members for their contribution to the conference.

All papers published in this volume of Journal of Physics: Conference Series have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

Tungsten is going to be implemented as a material for plasma-facing divertor tiles in an ITER tokamak. Accumulation of dust particles due to exfoliation of redeposited tungsten layers can severely affect the operation of a fusion devices. Behaviour of tungsten films deposited on tungsten, including layers with added impurities of iron (0,2 at.% and 2 at.% concentration), as well as dust particles with Al impurity, has been studied. It is shown that a film with 2 at.% impurity of iron exhibits exfoliation and blistering when exposed to thermal and radiation loads, while tungsten dust particles with aluminium impurity undergo various structural changes depending on their Al content when heated.

The electronic and local atomic structure of lutetium metalloporphyrins Lu(acac)TPP and precursor tetraphenylporphyrin (TPP) have been studied by X-ray photoelectron spectroscopy (XPS) and absorption spectroscopy (XAFS). The XPS spectroscopy data show changes in the electronic structure of tetraphenylporphyrins under incorporation of the lutetium atom: a redistribution of the electron density between the nitrogen atoms of the pyrrole- and aza- group and appearance of one broadened peak of the N1s state. The integer trivalent state of the rare-earth metal (Lu³⁺) in metalloporphyrins has been confirmed by both XPS and XAFS methods.

Ti–Cr–B–N coatings were successfully deposited using reactive pulsed cathodic arc evaporation (CAE) of ceramic TiCrB target. The influence of the substrate negative bias voltage on the coating impact wear resistance and mechanical properties has been studied. Structural investigations have been carried out using X-ray diffraction analysis, transmission and scanning electron microscopy, glow-discharge optical-emission spectroscopy, and optical profilometry. The coating properties have been estimated by impact tests, scratch-test, and nanoindentation. The obtained results show that the coatings consist of Ti(Cr)N fcc phase with crystallites 1–2 nm in size and amorphous BNx tissure. The coatings obtained at U_bias=-250 V demonstrated highest hardness of 24 GPa, whereas samples deposited at U_bias=-500V exhibited minimal wear rate (worn area of 12 μm²) in impact conditions. Coatings obtained by pulsed CAE with intensive ion-bombardment possess high adhesion strength higher than 120 N.

Algorithms for modelling of multicomponent polydisperse systems using small-angle scattering data have been developed. They cover a wide range of particle form-factors and take into account interparticle interactions. The algorithms are implemented in computer programs MIXTURE and POLYSAS, and their performance is tested on a number of simulated and experimental examples. The stability of the solution search is explored for the case of a two-component polydisperse system of spherical particles.

High-temperature superconductors (HTSC) have a significant potential for application in systems based on magnetic levitation. The wide spread of second-generation HTSC tapes (CC- tape from coated conductors) allows the use of stacks of CC-tapes as an alternative to bulk superconductors, particularly in levitation systems. The paper presents the results of research of CC-tapes of various manufacturers - SuNAM, THEVA and SuperOx. The tapes were cut into square 12 mm × 12 mm fragments and stacked in stacks, the number of tapes varying from 10 to 100. The measured dependences of the levitation force on the distance between the magnet and the stack have similar patterns for tapes of all manufacturers - the force of interaction increases with increasing thickness of stacks. However, the influence of the thickness of the stack on the levitation force for different CC-tapes is of a different nature.

We have studied the effect of synthesis methods on the structural state and magnetic hysteresis properties of the NdFe₁₁Ti compound with ThMn₁₂ structure obtained by arc- melting, annealing, melt spinning and nitriding. We found prolonged high-temperature annealing and melt spinning form a single-phase state. However, the grain size of the alloy after melt spinning is 1000 times as less which leads to high magnetic properties as compared to annealing. Nitriding increases the magnetic hysteretic properties after both annealing and melt spinning.

A comparative analysis of the abilities of several novel methods to produce ultrathin molybdenum disulphide (MoS₂) films containing from 1 to 10 molecular layers was carried out. To deposit MoS_x films and MoO_x precursor films, the atomic flux was formed by laser ablation of Mo, MoS₂, and MoO₃ targets. Saturation with sulphur of the deposited layers was performed using a reactive gas (hydrogen sulphide) or by thermally activated treatment of thin-film precursors in a sulphur vapor. It has been established that the use of hydrogen sulphide makes it possible to obtain ultrathin MoS₂ films at relatively low temperatures ∼ 350 °C. However, these films contained local defects which were absent in the films prepared by the treatment of thin film MoO_x precursors in sulphur vapours at higher temperatures (≥ 650°C).

Thin-film precursors of BC_x were formed by pulsed laser codeposition of boron and carbon. Targets made of pressed boron and carbon powders with an equal element content (B/C = 1/1) and an increased carbon content (B/C = 1/3) were used. The films were deposited on sapphire substrates at elevated temperature (700°C) which determined the initial properties of the precursor BC_x films. Irradiation of the films was carried out by laser pulses of nanosecond duration with varying intensity. The films obtained by laser annealing of BC_x (Q-BC_x) were studied by scanning electron microscopy and micro-Raman spectroscopy. Irradiation under optimal conditions made allowed to realize pulsed melting of the films and partial preservation of their continuity on the substrate. The local structure of Q-BC_x films and the nature of the changes in their electrophysical properties depended on the composition of the precursor films and the laser irradiation regimes.

Influence of synthesis conditions on the crystal and local structures of WO₃ powders prepared by thermal decomposition of ammonium paratungstate and precipitation of tungstates aqueous solutions in strong acid conditions has been investigated. Combination of X-ray powder diffraction, X-ray absorption fine structure spectroscopy, IR- and Raman-spectroscopy, and scanning electron microscopy was used. The calcination of all initial compounds at temperatures ≥ 500°C led to formation of the monoclinic γ-WO₃ single phase. It was concluded that the neutral octahedral complex [W=0(0H)₄(H₂0)] can be a structural unit of the precursors prepared in acidic suspensions. The local structure of synthesized tungsten oxides consists of edge-shared and corner-shared distorted octahedral WO₆ species linked together.

Using the self-consistent approximation we calculate conductivity in an anisotropic heterogeneous media with superconducting inclusions and compare the results with those obtained previously using the Maxwell approximation and with available experimental data on excess conductivity above T_c = 8K in FeSe. Advantages and drawbacks of these two approximations are discussed. The obtained analytical formulas can be applied to various other anisotropic heterogeneous superconductors, including high-T_c layered superconductors.

The influence of pulsed laser deposition conditions in the geometry "off-axis" on the catalytic properties of MoS_x films in the hydrogen evolution reaction is investigated. For the deposition of MoS_x films from MoS₂ target, pulsed laser radiation from the IR and UV wavelength ranges was used. The angle of incidence of the laser-induced plume on the surface of the substrate in a buffer gas was varied to check the influence of large in-size Mo-enriched particles. The efficiency of the catalyst was estimated from the results of the turnover frequency (TOF) measurement, which made it possible to minimize the influence of the "loading" of the catalyst on its characteristics. The effects of the chemical composition, local structure, and properties of the catalyst–substrate interface on the efficiency of the hydrogen evolution reaction are analysed. The regime of pulsed laser deposition of more effective thin-film MoS_x catalysts is determined.

The conditions of the detection of nitro compounds vapors was investigated using the trinitrotoluene as an example. The detection method consists of pyrolysis and later registration by the MIS-sensor of gaseous products of thermal decomposition . It was shown that the offered method allows to achieve the detection limit of 1·10^-12 g/cm³ (particles – 1 ng) with respect to the vapors of trinitrotoluene.

The behavior of detonation nano- and microdiamonds at increased temperatures is studied by synchronous thermal analysis, X-ray diffraction analysis, and scanning electron microscopy. The X-ray analysis of survived samples shows that a part of the nanodiamond is stable under heating to 1500°C. At the heating to 600°C, we see the decreasing of nanodiamond phase. Appearance of graphite phase isn't observed in the sample up to 1500°C. However, in the range Bragg angle 20-32° after heating to 1500°C, the x-ray amorphous graphite-like phase is observed. The analysis of microphotographs of samples before and after heating showed the influence of heating rate on the parameters of powder particles. A high thermal stability of detonation microdiamonds (above 1500°C) is established. Literature data on the radiation stability of diamond are analyzed. It is established that the character of the diamond damage depends on the type and dose of the irradiation.

We study the change in the shear elasticity of a viscous fluid near a solid surface of a metamaterial. The interest in studying the shear mechanical properties of these fluids is caused by their wide use in engineering. Surface forces in boundary layers or thin films of classic molecular systems should be considered when describing different phenomena in near-surface layers. We obtained the solution for two-particle distribution function at low densities. It is shown that the solution describes the transition from axial to spherical symmetry while each particle goes to infinity.

By using the Monte Carlo method, a numerical study has been conducted to calculate the current-voltage characteristics of a high-temperature superconductor with intrinsic pinning sites and the additional ones in the form of antidots in different magnetic fields. Varioustypes of antidot distribution among the sample such as a random distribution, triangular and square lattice and their conformal transformations, have been considered. Descending critical current density dependencies on the magnetic field for different samples have been acquired. Averaged vortex configurations of samples for different antidot distributions at the same magnetic field and transport current have been acquired. The most effective antidot distribution has been determined.

In order to reveal the influence of the tilt angle of columnar defects on angular dependence of critical current density the Monte Carlo simulation of vortex system in three-dimensional layered high-temperature superconductor (HTSC) was performed. For simulations, the three-dimensional model of layered HTSC generalized for the case of tilted magnetic field was used. The angular dependencies of the critical current were calculated at different splay angle of columnar defects and different anisotropy of HTSC. It was shown that simulation results correspond qualitatively to the experimental results for REBCO coated conductors.

The electronic, phononic, and superconducting properties of double hydrides YH₆and H₃S are analyzed and compared with that for triple hydride YS₄H₄ . A common physical and numerical approach was used to determine both the stability range and the critical superconducting temperature. The characteristics of the high-pressure phase of the triple hydride YS₄H₄ are obtained.

The paper analyzes numerically the hydrodynamic processes developing inside the fused quartz under the action of intense laser impulses. Depending on laser intensity two basic regimes are obtained and described in details. At low intensities, the slow regime driven by the heat transfer is observed. Herewith, the fracture took place in the heated region before the phase transition. At higher intensities, the high-speed propagation regime is established characterized by the fracture events exactly at the interfacial boundary between the hot plasma and condensed phase. The propagation of absorption wave coupled with the fracture wave is limited by the value of sound speed in the hot plasma, which determines the expansion of plasma into the spallation region ahead of the absorption front. The proposed model of the process agrees well with the recent experimental data, in particular with the characteristic velocity scales.

About a half of the Fermi surface in rare-earth tritellurides, RTe₃ becomes gapped below the transition to a charge-density-wave (CDW) state, as revealed by ARPES data. However, the observed jump in resistivity during the CDW transition is less than 20%. Previously this phenomenon was explained by hypothesizing a very slow evolution of CDW energy gap below transition temperature in RTe₃ compounds, which contradicts the X-ray measurements. Here we show that this weak change in resistivity can be explained in the framework of standard mean-field temperature dependence of the CDW energy gap in agreement with X-ray data. The change of resistivity caused by CDW is weak because the decrease in conducting electron density at the Fermi level is almost compensated by the decrease in their scattering rate. We calculate resistivity in RTe₃ compounds using the Boltzmann transport equation and the mean-field description of the CDW state, and obtain a good agreement with experimental data.

In this work we present a computational model for a magnetic levitation system based on stacks of 12 mm x 12 mm second generation GdBa₂Cu₃O_7-x high temperature superconducting (HTSC) tapes. In our model we have used the magnetic and transport characteristics of real industrial HTSC tapes. The thermal properties of each layer of high-temperature superconducting tape and the features of the layered structure of whole stack have also been taken into account. The numerical simulation was performed using the finite element method. Distributions of both magnetic field throughout the space and the current in every tape of the stack were calculated for two cases: (i) cryocooler cooling mode and (ii) cooling in the liquid nitrogen. The magnetization curves of the stacks in external field of a permanent NdFeB magnet and levitation force dependence on the gap between the magnet and the HTS tapes stack in these cooling modes were obtained. We have calculated heat transfer and temperature distribution in the system taking into account the effect of thermal properties of Hastelloy substrate, as well as Cu and Ag stabilization layers on the cooling process and dynamic magnetization. Simulation results were compared with the experimental data and a good agreement with numerical ones was shown.

Structure and electronic properties of small Au nanoclusters study was performed using density functional theory with pseudopotential in relativistic approximation. Density of states of the valence band, projected density of states was calculated, Bader charge density analysis is presented. The spatial behavior of the density of states was studied. Charge-momentum spatial anisotropy observed in symmetrical nanoclusters, electronic states on Fermi level of 1nm clusters founded to be caused mostly by d_5/2 surface states.

termal annealing effect on electron transport properties of MHEMT nanostructures is studied for inhert and atmospheric conditions. Iti is revealed that surface modification is mainly responsible for changes in electron properties rather than dislocation sliding and threading into active layers.

In this work the Seebeck coefficient of simple model of nanoclustered material with respect to bulk form was investigated. The first-principle calculation of Seebeck coefficient of the bulk and model nanoclustered form of Ta was performed via semiclassical Boltzmann transport approximation with constant relaxation time, using first-principal bandstructure calculated in density functional theory. 5-15-times increasing of Seebeck coefficient was estimated for simple model of nanoclustered material.

The seismic situation in a number of rooms of the NRNU MEPhI, including the Laboratory Building, where the construction of the multifunctional laser complex ELF is planned, is studied. Estimations of seismic and vibrational noise at the main and isolated parts of the basement of the room that hosts the laser complex are obtained.

The article describes a multichannel modular system for velocity measuremens in shock physics. The two-channel time compression system is based on PDV method. It was tested in lead dusting experiments.

The research and comparison of spectroscopic methods for assessment of skin grafts engraftment/rejection after the back cross skin transplantation of laboratory mice were carried out. The spectral analysis was performed via inflammatory reaction evaluation of the studied area. The inflammatory reaction intensity correlates with the fluorescence intensity of the aluminum phthalocyanine nanoparticles. The photodynamic therapy was carried out to improve the skin engraftment and reduce the inflammatory reaction.

VISAR type measuring laser systems are used for the determination of surface velocities in high-speed processes. Their operational characteristics mostly depends on the efficiency of collection of scattered radiation. In this paper we present results of the comparative analysis of several radiation collection schemes along with experimentally obtained data on the scheme parameters effect on collection efficiency and recording length.

The paper considers the possibility of using laser milling technology for precision processing of ceramic samples from pre-sintered and sintered ceramics zirconia and lithium disilicate. To find the best radiation source were compared different lasers. To find highest removal rate with acceptable accuracy was studied influence laser and scanning system parameters on ceramics. Accuracy problem of laser milling was considered. Examples of surfaces of prostheses were made.

The microstructure of 316L stainless steel obtained by layer-by-layer direct metal laser deposition is reviewed. Mechanical tests of the samples were performed in accordance with GOST 1497-84. Studies show that changes in power of laser radiation to grow parts lead to changes in their mechanical properties. The research shows dependencies between the strength characteristics of materials and the power of laser radiation. Causes of the forementioned changes are studied through the analysis of the microstructure. Nanosized inclusions of spherical shape were found in the process of studying the microstructure of materials. A study in the nature of the formation of these inclusions and their effect on the properties of the obtained material was performed.

Nano- and micro-structures of thin plasmonic films by focused femtosecond laser pulses was demonstrated as chemo- and bio-sensing substrates for surface-enhanced spectroscopies. As an example, large regular arrays of microholes (mm-sized laboratory-scale) of millions holes with variable periods were produced in thin films of diverse plasmonic metals or alloys, demonstrating surface plasmon-polariton enhanced extraordinary transmission.

The article experimentally investigated the phenomenon of filamentation in the propagation of femtosecond laser radiation in transparent solid media. The experimental scheme for measuring the parameters of filaments using spherical and cylindrical optics was developed and assembled. A series of experiments on the spatial ordering of filaments was carried out. The sample was structured in the filamentation mode with a predetermined distribution of laser radiation intensity. The spatial redistribution of laser radiation passing through the formed structures in the quartz glass sample is also investigated.

We present the results of 3D thermal regimes modelling of CW laser diode arrays (LDA) assembled on the CS-mount type heat sinks. The dependences of the LDA temperature profiles on the fill factor (FF) of the LDA aperture at different levels of thermal load in different sections on LDA, including those inaccessible for direct experimental measurement calculated and discussed.

A method for the synthesis of microspheres coated with titanium carbide is described. The processes occurring in the region of the action of laser radiation are considered. The formation of microspheres was carried out by the action of femtosecond laser radiation on the surface of titanium located in the reaction medium - the ultimate hydrocarbon. The hydrocarbon source was the medium in which the treatment was carried out. The obtained microspheres have an average size of 1-3 μm and can be used in applications of additive engineering, powder metallurgy as the main raw material, or as an alloying additive.

X-ray photoelectron spectroscopy technique have been used to study carbon films obtained by means of ion-plasma deposition in the plasma of different chemical composition. The detailed analysis of electron spectroscopy data made it possible to determine the structure of the films and the influence of nitrogen and hydrogen admixture in plasma on the structural properties. Diamond-like films are obtained in pure argon plasma, graphite-like and carbon chain structures correspond to nitrogen and hydrogen addition respectively.

Nanostructured coatings HfO₂-9wt%Y₂O₃ were obtained by plasma spraying in vacuum using supersonic nozzle creating Prandtl-Mayer expansion fan. The coatings were investigated by scanning electron microscopy, X-ray diffraction analysis, and synchronous thermal analysis (differential scanning calorimetry, thermogravimetric analysis, and differential thermogravimetric analysis) in the temperature range of 40÷1600°C. The coatings are predominantly characterized by the nanostructured globular structure. Thermal analysis showed a peak corresponding to the exothermic reaction in the temperature range of 1400÷1600 °C, accompanied by a mass loss. c-HfO₂ phase remained in the coating after thermal analysis with a decrease in the lattice parameter a from 5.18 Å to 5.13 Å.

The results of research on the effect of the presence of viscosity on evolution of perturbations in the system of colliding plates are presented in this work. The range of amplitudes of the initial perturbations wavelengths, at which the effect of viscosity may be neglected, are determined. Comparison of analytical and numerical results are shown.

Numerical analysis of the hydrostatic equilibrium of a compressed gas bubble was carried out by the DFT method. Based on this analysis, we modified the hydrodynamic equations of a quantum fluid taking into account quantum shell effects. An external force acting on the electronic subsystem is added to the modified hydrodynamic equations. A numerical algorithm for solving of the system of modified hydrodynamic equations is discussed.

Absorption features in cells with antirelaxation coating in D₂ -lines of alkali metal atoms due to the competition of cyclic and open transitions lying within the Doppler contour are studied. In cells of this type ensemble of atoms is optically pumped over all velocities and the entire volume of the cell during the characteristic time T, which noticeably exceeds local pumping times related to resonant atomic velocities. If the frequency scanning T, the retardation effect results in significant distortion of the laser wave absorption contour and to emergence of the hysteresis phenomenon. The developed theory for a realistic scheme of atomic levels with one cyclic and two open transitions describes experimentally observed absorption contours, their dependence on the light power and the frequency scanning direction.

The article presents the results of laser mass-spectrometric analysis of surface of the samples, exposed to long-term treatment with high current discharges in the fluid flow (water with admixtures of different composition). It has been found, that the elemental composition of the surface of the metal, in particular, oxygen-free copper, can vary considerably (up to 35 at.%) compared to the original composition (99.8 at.%) to a depth of up to 10 μm. Change of the isotopic composition (isotope concentration of 65 amu may amount to 38.1% while the normal rate is equal to 30.6%) has been indicated. Composition of water (distilled water, tap water, saline water) does not affect the results. The concentration of elements, such as Cl, may exceed the original concentration by 3,000 times. At a depth of 10 μm, the composition is similar to the original one (before the exposure).

In this work, the impact of the plasma treatment, during the formation of nanostructure arrays on the surface of the Cu(In,Ga)Se₂ films on glass substrates, on the conductivity of the films both in the lateral direction and in the direction normal to the substrate surface was studied. The initial Cu(In,Ga)Se₂ films with the Ga/(In + Ga) ratio in the range of 0.03–0.12 were obtained by thermal selenization process of stacked metallic precursors and by co-evaporation of all elements from various sources. The plasma treatment was carried out in a high-density low-pressure RF inductively coupled plasma reactor in argon plasma. The average ion energy was 200 eV, the processing time was 60 s. It is shown that the processes of the plasma nanostructuring of the Cu(In,Ga)Se₂ film surface lead to the formation of a thin modified near-surface layer with a resistivity of 2–3 orders of magnitude less than for the bulk of the film.

We study transmission of unpolarized light (incoherent superposition of right-hand circular and left-hand circular polarized waves) through an optically active medium doped by scattering Mie-particles. The medium is assumed to possess circular dichroism. Within the spatial diffusion approximation, the degree of circular polarization of the transmitted radiation is calculated. It is shown, that in the presence of scatterers a significant increase in the circular polarization compared to the medium with no scatterers can be observed.

It is shown that the one-particle radial Dirac equation with a spherically symmetric narrow rectangular well remains valid also in the supercritical region. Positron resonances in scattering arising at low supercriticality are in no way related to the process of spontaneous production of electron-positron pairs from vacuum.

We study the total reflectance of an absorbing, multiply scattering medium with large (as compared to the light wavelength) inhomogeneities at grazing incidence of light. To model highly forward scattering in the medium, we take advantage of the two-parameter Reynolds-McCormick scattering phase function. Using the scaling analysis for the small-angle radiative transfer equation, we derive simple analytic formulae for the dependence of the reflectance on the medium transport coefficients and the angle of incidence. The results obtained are verified by comparison with results of a direct numerical integration of the radiative transfer equation.

The results of numerical simulation of plasma flow in the channel of technological radio frequency inductively coupled plasma (RF–ICP) with three coils are presented. The generator frequency is varied from 1.76 to 13.56 MHz. The pure argon or Ar/H₂ mixture are considered as the working gas. The volume fraction of hydrogen in Ar/H2 mixture is varied from 0 to 10%. The distributions of gas-dynamic parameters of plasma flow are calculated. It is shown that when the amplitude of discharge current exceeds a critical value (depends on volume fraction of hydrogen), the states of plasma flow transform from potential to vortical patterns, in which a toroidal vortex is found in front of the inductor zone. The dependencies of critical current on the generator frequency and volume fraction of hydrogen are established. The influences of generator frequency, volume fraction and discharge current on the intensity and coordinate of vortex tube are determined.

Based on experimental and computer simulation the acceleration of deuterons from laser plasma in a strong non-stationary magnetic field was studied. The possibility of reaching an energy of ∼100 keV, corresponding to the effective course of the nuclear reactions D (d, n) ³He and T (d, n) ⁴He, was demonstrated. YAG: Nd³⁺ laser (W ≤ 0.85 J, τ ≈ 10 ns) was used in the experiment with focusing laser radiation on a deuterated polyethylene target. The high voltage pulse generator with a conical spiral coil was used to generate a high-speed magnetic field (2·10⁷ T/s). A mathematical model of the process is proposed. According to this model, the acceleration of a laser plasma is analyzed by means of a computer. The algorithm is based on a numerical solution of the system of Newton-Lorentz equations.

The parameters of a non-catalytic process for synthesizing carbon nanostructures during the conversion of methane / helium and propane-butane / helium jets have been studied. The spectral features of the radiation of mixed systems have been investigated. Analysis of the spectra showed that the main part of carbon dimers is withdrawn from the hot region of the plasma in the outlet plasma stream. Synthesized products were been characterized by scanning electron microscopy, Raman spectroscopy, thermal analysis and X-ray photoelectron spectroscopy. It is shown that carbon nanostructures have a bamboo-like morphology and similar properties when using both methane and propane-butane mixture as a carbon source. It has been established that the morphology of synthesized carbon nanofibers is not affected by the pressure of the medium.

Properties of the corona discharge containing a conic electrode were researched. The main modes and characteristics of this discharge were researched. There are current oscillations of the discharge within the range of 1 kHz - 150 MHz. Possible oscillation and wave processes are considered to explain these oscillations. Emergence of rotation motion when the discharge affects the dielectrics is being studied. The effect of this discharge on metal surface was explored.

It is proposed to control plasma turbulence near the LCMS of a tokamak with a system of electrodes made from porous tungsten. We propose to apply the RF modulation at the ion-cyclotron resonance frequency for driving of fluctuations near the LCMS. Porous tungsten plates used as biasing electrodes are the advantage to increase the emissivity of the porous surface and to reduce a surface erosion. To reduce the drag and thermal load on streamlined surfaces at supersonic and hypersonic speeds, it is proposed to cover the aircraft with materials of high porosity. The first experiments were carried by using model with fractal surfaces having non-Gaussian height statistics from ∼ 500 nanometers to ∼ 200 micrometers obtained by plasma treatment. The advantage of such a surface is the coincidence of the spectral and statistical characteristics of the stochastic topography of the surface with the turbulence characteristics of the flow.

The paper presents the issues related to the development of a portable neutron generator with a microwave source of heavy hydrogen ions for a wide range of applications. The paper analyzes the effect of electromagnetic microwave field strength and the magnetic induction value of a constant external magnetic field on the ionization rate of molecular deuterium and determines their optimal ratios. It also describes the configuration of the magnetic system of permanent magnets made of NdFeB material, which provide a homogeneous magnetic field with an induction of 850 Gs necessary for the effective operation of the device using the electron cyclotron resonance (ECR). The dynamics of the primary deuteron flux, as well as secondary particles in the ion-optical system are analyzed. Elements of a conceptual design of a portable neutron generator are described.

We studied low-temperature plasma effects on Paramecium caudatum using the original electric arc plasmatron. The decrease in the number of experimental cells has been shown, which may indicate membrane destructive pathology due to oxidative stress induced by the plasma impact. It is concluded that reactions at the population level of Paramecium caudatum are effective indices of primary information about plasma radiation cytotoxicity.

Bi-metal targets of ZnSn and SiAl were sputtered in A+O₂+N₂ gas mixtures at various N₂/O₂ ratios, and the deposited films were investigated by AFM and XPS. No nitrogen was detected in the films even at the highest nitrogen partial pressure in the gas, and the films were oxides. The concentration of the doping metal component in the deposited film increases with the increase of nitrogen partial pressure in the working gas. These experimental observations were supported by numerical calculations of the sputter-deposition process using a SRIM/SIMTRA+RSD software. It was shown that added nitrogen promotes sputtering of doping metal components of the targets, and the concentration of oxygen remains high enough to substitute the less active nitrogen in the growing film. The films consisted of nanograins with the average diameter, which decreased from 18 nm to 3 nm with increase of nitrogen content in the working gas. This effect was explained by the mechanism of abnormal grain growth: the film consisted of grains of oxides of two metals with different concentrations. The doping metal forms very fine nanograins of oxides, which suppress the growth of oxides of the main metal. With increase of nitrogen in the working gas mixture, the sputtering rate of doping metals from the cathodes and their respective concentration in the growing films increases, so the average diameter of oxide grains forming the coating decreases.

Formation of semiconductor nanostructures on the surface of single crystalline silicon and germanium wafers by spark discharge plasma in air was investigated. The prepared nanostructures were analyzed by means of the scanning and transmission electron microscopy and optical spectroscopy of the photoluminescence and Raman scattering. The formed nanostructures exhibit a fractal-like morphology with interconnected nanocrystals of 2-200 nm sizes that is explained by repeated processes of spark ablation and subsequent condensation. While the size and morphology of the nanostructure depend on power sources of the spark discharge, short interaction times of spark discharge plasma and target determine a relatively low efficiency of the chemical oxidation of germanium and silicon, as well as low ionic temperatures of the plasma.

Studies of the spectra of the radiation source based on the Z-pinch of multiwire arrays on the Angara-5-1 facility are presented. Their intensity and character change drastically during the radiation pulse. The instantaneous spectra of Z-pinch radiation differ substantially from time-integrated spectra close in shape to Planck's, their shape depends on the time of their recording and is characterized by the presence of bands which, according to calculations, correspond to the 4d-4f transitions (in the wavelength range greater than 120 Å) and 4d-5p (less than 120 Å) in tungsten plasma with an average ionization ∼14 and a temperature of ∼40 eV.

This work gives an analysis of the coating obtained by electro-spark alloying using TiCNiCr electrode regarding their composition, structure, morphology, roughness, and mechanical properties. Tribological properties were studied by pin-on-disk test against different counterparts without lubricant. Soft materials like Cu, 100Cr6 steel are not damaging the coating and hard materials are either a good couple like with WC-Co, or characterized by a aggressive wear like with SiC, Si₃N₄, Al₂O₃. Detailed microscopic investigations of the tracks were done after tribo-tests.

The study of the ionized environment in the area surrounding PDFL has showed the presence of visible plasmoids moving in the horizontal plane. The study of traces on the X-ray film made it possible to detect a significant number of traces of an identical shape and size that look like the "birds" which were found earlier in other facilities. A preliminary analysis has been carried out for their identification, which led to a conclusion about the nature of these formations, in particular, their identity with the Dirac monopole (or similar object) having a "tail" and "wings" formed by a flow of electrons from the surroundings.

Periodic discharge in water flow was investigated using optic spectrometer and 1000 fps video camera with the discharge pulse up to several milliseconds long regulated by water flow speed. Copper drops were found on the cathode surface in the case of copper-tube anode. In spite of water cooling anode can reach melting point. Optic spectra were compared for several materials of electrodes. For copper electrodes it was found that anode is the main contributor of copper in discharge plasma.

The microstructure, phase and element composition, microhardness of the carbon steel surface layer simultaneously alloyed with molybdenum and chromium atoms under the impact of compression plasma flows were investigated in this work. X-ray diffraction analysis, scanning electron microscopy, energy dispersion microanalysis and microhardness measurements were used for the investigation of the alloyed layer structure and properties. The findings showed that an increase of the plasma pulses number led to a decrease of the molybdenum and chromium atoms concentration in the alloyed layer as well as to the growth of alloying elements distribution homogeneity. The alloyed layer contained solid solutions on the basis of α-Fe and γ-Fe according to the data of the phase composition analysis. Plasma impact resulted in 3.5 times microhardness increase due to structure refinement.

Optical radiation from plasma of abnormal glow discharge in Ar+N₂, He+ N₂ and N₂+H₂ was investigated. Lines of N₂ N₂⁺, N, N⁺, Ar⁺, Ar, He, Fe, H, H₂ and OH were detected by optical spectrometry. Discharge current and intensities of spectral lines of N₂, N₂⁺, N, and N⁺ versus the concentration of Ar, He, and H₂ in the gas mixtures were measured at various compositions of the working gas.

The analytical solution is found for thermodynamic state of plasma created when the half-space is heating by high-energy ion flow. The dependence of free path length of heating ions on plasma temperature is taken into account. Besides, an analysis of characteristic parameters of shock wave and efficiency of energy transfer to shock wave from heating ion flow is given.

Experimental results and computer simulations of electrodynamic and thermodynamic characteristics are presented for an accelerating structure that is excited in the $T{M}_{010}^{0}$ mode and that has the accelerating channel of URAN-1M located in the diametric plane. The idea of using this structure in the particle accelerator URAN-1M, located at the Baikov Institute of Metallurgy and Materials Science, with the goal of increasing the average beam current is explored. The experimental study and the computer simulation of accelerating structure excited in E010 mode that has accelerating channel of URAN-1M placed in the diametric plane of structure resulted in R_sh = 165 MΩ/m and Q₀ = 9736. To form an accelerating field identical to that of URAN- 1M, the structure requires less than 15 kW RF power. Thermal analysis showed that if the main parts of the structure are water-cooled, the structure could operate in CW regime.

The Future Circular Collider (FCC) study aims at designing different options of a post- LHC collider. The high luminosity electron-positron collider FCC-ee based on the crab waist concept is considered as an intermediate step on the way towards FCC-hh, a 100 TeV hadron collider using the same tunnel of about 100 km. Due to a high intensity of circulating beams the impact of collective effects on FCC-ee performance has to be carefully analyzed. In this paper we evaluate beam coupling impedance of the FCC-ee vacuum chamber, estimate thresholds and rise times of eventual single- and multibunch beam instabilities and discuss possible measures to mitigate them.

The developed and currently manufactured debuncher for the injector part of the accelerator facility NICA is designed to reduce the energy spread by a factor of up to ten in the ion bunches with Z/A=(0.33-1) at the output of the LU-20 linac. The debuncher includes a Split-Ring cavity, a vacuum system, a solid-state RF amplifier and an RF controller. The main design parameters are described.

Consuming long-range interplanetary medium as a fuel for driving plasma thrust is crucial. The methods of capturing the space environment depending on its density and the ship velocity are critical issues. The possible ways of creating ionization for neutral fluxes as a function of the solar radiation flux are also analyzed as a potential propellant. These processes define the permissible type of the plasma source. These options look extremely promising where a low thrust device continuously operating, could possibly deliver a celestial target close to the speed of light. Under such conditions at a considerable distance, the density of such material diminishes and it may be impossible to maintain a continuous operation mode of the plasma thruster but instead operate as a pulsed engine which might potentially be workable.

Photoemission in modern high brightness electron sources is under studies at the PITZ photo injector. Space charge dominated photoemission in the presence of high RF field at the semiconductor photocathode is studied. By utilizing core and halo particle distributions based on measured radial laser profiles, simulations reproduce the behaviour of the measured emission curves for a wide range of RF gun parameters within the measurement uncertainties for Gaussian laser pulses. But applying this model to the case of long flattop photocathode laser pulses revealed discrepancies between experimental data and simulation results. Corresponding emittance simulations have been compared to measurements for both temporal profiles of the photocathode laser.

The report deals with the construction of the ion beam transport line for applied and biomedical research at the NICA accelerator complex, JINR, Dubna. Calculations of the beam output channels from the Nuclotron and Booster are carried out. The used electronics is described. We also discuss the compilation and realization of the plan of treating a tumor located at a depth up to 30 cm.

The results of development, installation and tests of an experimental facility for irradiation of different products and materials at the INR RAS linear accelerator are presented. The beam energy range is 20÷210 MeV. The energy is adjusted by switching on/off the fields in accelerating cavities and with energy degraders. The intensity range is from 10⁷ protons per separate pulses up to 1 μA of average beam current. Also the activation of the beam dump and the test unit as well as the radiation conditions in the vicinity of the facility are estimated.

Quadrupole fields are considered as an option for beam asymmetry compensation for L-band photoelectron guns used at DESY. The quadrupoles dedicated for the installation at a gun coupler region have three designs. The first two designs were installed and tested with photoelectron beam. The designs of the quadrupoles and experiments results are presented.

Discussed two options for increasing the magnetic isolation efficiency of the electron component in a vacuum neutron tube with coaxial geometry for the acceleration of deuterons. Computer analysis of the previously developed diode systems with magnetic insulation has shown that the suppression ratio does not exceed 50%. The proposed new options of suppression systems used the current ring and diaphragm, located near the edge of the cylindrical anode. Computer analysis showed that for these acceleration geometries the suppression factor could exceed 97%.

Extraordinary emittance requirements in the nm range (normalized) and pulse lengths down to a level of ∼10 fs for REGAE bunches demand both operation at low bunch charges on the sub-pC scale and a very careful beam handling. The S-band RF deflecting cavity is intended for diagnostics of the longitudinal bunch parameters. For the first time a deflecting structure, specially developed and optimized for bunch rotation has been realized for the REGAE RF deflector. The developed cavity provides a minimized level of aberrations in the distribution of the deflecting field combined with an improved RF efficiency. The main steps in the cavity design, construction and tuning are described.

The paper is devoted to intense quasiperiodic beam dynamics investigation on the basis of integro-differential mathematical model. Space charge density representation by trigonometric polynomial makes it possible to obtain Coulomb field analytical expression in the same form. Space charge field is presented by the integral over particle phase states domain. Beam quality criteria are suggested in the form of integral functionals. Beam dynamics optimization problem is formalized as trajectory ensemble control problem. Analytical expression of objective functional variation is obtained; it makes possible directed optimization methods using. Numerical simulation and optimization results are presented for linear waveguide accelerator.

Numerical simulation of 3D electron dynamics in classical Lebedev institute microtron with energy 6-10 MeV is carried out. Special attention is paid to particles transversal motion investigation. A comparison of physical electric field distribution along cavity axis with that obtained by means numerical calculation is done. The obtained results are discussed.

The general layout for Specialized Synchrotron Radiation Source 4th generation SSRS 4 is under development by leading of National Research Center "Kurchatov institute". In the framework of a collaborative project with European Synchrotron Radiation Facility (ESRF) supported by the Ministry of Education and Science of the Russian Federation, the applied research on determination of the configuration and key technical parameters for the control and beam diagnostic systems for 4th generation Specialized Synchrotron Radiation Source – SSRS- 4 is going on. The preliminary view of the proposed control and diagnostic system is presented and discussed. SSRS-4 inherits the experience of the scientific community including a great ESRF expertise in control system development (as founder of TANGO), robust diagnostics and long operational experience on ESRF's accelerator.

The problem under study is global extremum search for multiextremal function. Random search method based on Markov chains simulation is used. A comparative analysis of this method with another method – the method of random search for the global extremum with "memory", using the normal distribution – done.

The examples of experimental studies of oil stratum debit restoring by method of ultrasound influence to stratum are given. The method of control of such unprocessed oil stratum restoring is proposed. It uses well neutron generator with vacuum accelerating tube and neutron reagent method with pumping of neutron absorbing salt solution to stratum. The results of its successful testing are presented.

Solid state amplification technology had developed a lot in recent years. This article is focused on a power combining system of a new power amplifier stage for ISIS neutron source (Rutherford Appleton Lab., STFC, UK). The amplifier is based on a modular block-built architecture that intends using of amplifier modules and combination of their output power (of >kW levels) using high power RF combiners. The power combining system for high power RF amplifier is discussed in this article. The system scheme together with results of modeling, low power measurements of key electrodynamic characteristics and high power operation test are presented.

It is very important task to define the tolerances necessary for correct operation of an electron linac. The detuning of linac main parameters as frequency, RF field amplitude and phase can sufficiently influence to the beam parameters. It is highly important for linacs with high brightness beams which are necessary for light sources and colliders. It is also sufficient for industrial linacs. A linac section consists of regular and bunching parts. The influence of one cell detuning on electrodynamics parameters of the whole section was studied. Results of such simulation will discuss in this paper.

The report discusses processes of light nuclei stopping in a solid-state barrier. Accounting algorithm of energy losses of light nuclei for (0÷20) MeV - range was considered. Calculated functions of the energy losses for various materials were presented.

The calculations of electron beam characteristics in the accelerator of sterilization installation with the local radiation shielding in relation to the use of a magnetron with a larger pulse power are made. It is shown that a simple method on the basis of "moving" of cathode- heating unit toward the anode plane of the injector may be used for increasing of current and power of accelerated beam.

Two distinct storage ring designs have been proposed for the deuteron Electric Dipole Moment (dEDM) search experiment: a Frozen Spin, and a Quasi-Frozen Spin ring. The FS-ring allows for the most accurate measurement, but the continuous fulfilment of the FS condition is unrealizable. The QFS design relaxes the condition to only hold on average, at a slight cost of precision. [1] The goal of the present work is to investigate which design is preferable for the attainment of the target precision. This task requires one to model the spinorbital dynamics of the beam in both rings.