An Erratum to this paper has been published: https://doi.org/10.1134/S0020441221050249

Abstract A high-voltage pulse generator is considered that contains an output circuit based on series-connected assemblies of reverse switched-on dynistors and drift step-recovery diodes. It forms voltage pulses with a rise time of 4 ns and an amplitude of 24 kV across a load of 50 Ω. The results of using the generator for creating discharges in atmospheric air are presented. The generator forms discharge-current

Abstract The scheme of a laser Doppler two-beam anemometer of a liquid or gas flow based on an acousto-optic modulator on a TeO2 crystal is considered, which performs the functions of a beam splitter and a light frequency shifter. It is shown that the mode of acousto-optic diffraction, that is, axial two-phonon interaction at a slow acoustic mode, is the most optimal for anemometer circuits. In this

Abstract The prospect of using high-voltage GaAs drift step-recovery diodes for the formation of subnanosecond pulses is shown. The electrical circuit of a generator is described, which provides (with a total efficiency of at least 25%) the formation of pulses at a load of 50 Ω with an amplitude of up to 550 V, a voltage rise time of 0.43 ns, a full width at half maximum of 0.73 ns, and a repetition

Abstract— An attempt to detect the soft X-ray pit (SXR-pit) phenomenon at the L-2M stellarator has been made in different plasma heating regimes using direct spectral measurements. The abnormally strong absorption of soft X-ray plasma radiation in its passing through beryllium foils with thicknesses of 90 μm or more is called the SXR-pit phenomenon; it has been observed at the T-11M tokamak and a number

Abstract A generator of high-power nanosecond pulses is described that contains a high-voltage unit, which is based on a magnetic-compression circuit and a diode current interrupter, and a high-voltage transistor unit, which provides high-efficiency energy switching to the high-voltage unit. The results of using this generator in an experimental plasma installation that was developed for studying the

Abstract Two versions of a forward hodoscope have been developed and manufactured based on scintillation and radiation-resistant quartz plates. The hodoscopes are designed to register ions in the BM @ N experiment at the NICA accelerator complex. The light outputs and their inhomogeneity were measured as a function of the coordinates of the passage of particles through the hodoscope plates on the calibration

Abstract— Optical fiber sensor is attracting more attention in the structural health monitoring of civil applications. A general interrogator which can be used for both SOFO and fiber Bragg grating (FBG) sensors has been proposed, it has a lower cost with a much simpler design. Its accuracy can reach up to ~2.5 με, it has a niche market where it can compete with the conventional sensors.

Abstract— Since 60Co gamma peaks in the gamma energy spectrum were not revealed in the electronic noise by the Multi-Pixel Photon Counter (MPPC), an experimental setup was proposed to reduce the noise, and to unveil the peaks and the gamma spectrum. For this purpose, constant fraction timing discrimination method was utilized. The timing signals were coincidentally gated in the multichannel analyzer

Abstract An apparatus is described for studying unsteady heat transfer in various liquid media by the method of controlled heating of a thin wire probe. The main link of the setup is a high-speed electronic regulator that controls the power dissipated by the probe depending on the control voltage at the regulator input. The main parameters of the apparatus are: the probe is a 1-cm-long 20-μm platinum

Abstract The phenomena that occur during internal heating (release of the control radio power) of an acousto-optic deflector based on paratellurite with heat removal from the piezoelectric transducer through a liquid contact were experimentally investigated. It was found that, in addition to the temperature drift of the velocity of sound and the refractive indices, the temperature inhomogeneity has

Abstract It has been noted that the main part of the magnetic noise in flux gates and magnetomodulation sensors with cores of amorphous ferromagnetic alloys obtained by the rapid quenching method arises as a result of strong magnetoelastic interaction. Recent advances in lowering the sensitivity threshold of active weak magnetic field sensors based on amorphous ferromagnetics are considered. An evaluation

Abstract A generator of high-voltage bipolar pulses with adjustable values of the switching frequency (0–2000 Hz) and the output-voltage amplitude (300–3600 V) with the same magnitude for pulses of different polarities has been developed. The rise time of the output voltage pulses when operating into a capacitive load of 400 pF is no more than 3 μs. The asymmetry of the effective values of the pulse

Abstract A method for physical modeling of the influence of bulk leakage-current channels (dislocations) on the electrophysical and lighting characteristics of LEDs by connecting the p–n junction of an LED in parallel to an ohmic resistance or another p–n junction is described. The relationships that allow one to determine the change in the electrophysical and lighting characteristics of LEDs under

Abstract— A prototype of the electromagnetic calorimeter for the GAMMA-400 γ-ray telescope has been calibrated at the Pakhra S-25R electron synchrotron of the Lebedev Physical Institute. The measured energy resolution of the GAMMA-400 calorimeter is consistent with the results of the Monte Carlo simulation. The applicability of the Pakhra S-25R accelerator for calibrating detectors in various experiments

Abstract— A multichannel scintillation spectrometer with a thickness of 2.5X0 has been calibrated on a secondary electron beam with energies of 23−280 MeV at the Pakhra accelerator of the Lebedev Physical Institute. The relative energy resolution of the spectrometer is determined by the electron energy and the spectrometer thickness. The best relative energy resolution of the spectrometer is attained

Abstract The results of modeling and optimization of a composite scintillator for recording thermal neutrons are presented. The interaction of thermal neutrons and γ-quanta with composites consisting of fragments of a glass scintillator containing 6Li was observed. The aim of the research was to determine the structure of a composite with high sensitivity to thermal neutrons and to provide effective

Abstract The arrangement and results of full-power experiments on the Iskra-5 laser facility (the laser energy is 150 J, the pulse length is 0.3 ns, and the laser-radiation intensity on the target is 1.6 × 1015 W/cm2) on focusing of hard X rays from a laser-plasma source with a Ga target using an ellipsoid with a HOPG crystal are described. The design of an ellipsoid focus pointer is described that

Abstract Using the same extremely noised data, two correlation methods for finding the maxima of Brillouin spectra are compared. The first method is a well-known method of correlating the received signal with the ideal Lorentzian function. In the second method, developed by the authors earlier, instead of the Lorentzian function, the same spectrum under study, but inverted along the frequency axis

An automated device is described that makes it possible to obtain maps of the spatial distribution of the composition and intensity of the components of the optical emission spectra of an activated gaseous medium, as well as to conduct thermometry using machine-learning methods based on a quick comparison of calculated and experimentally recorded radiation spectra. The interpreted Python programming

A neutron spectrometer with three energy channels and a particle reception angle of 15° has been developed and installed for joint use with standard detectors at the cosmic ray station in Apatity. This configuration of the device allows one to study the degree of anisotropy of the particle flux. The characteristics of the detector (response function and the angle of reception of particles), as well

The description and technical characteristics of the gamma-spectrometer installation for the detection of cosmic rays, as designed at the Dolgoprudny scientific station of the Lebedev Physical Institute in cooperation with the Mackenzie University (Sao Paulo, Brazil), are presented. This installation has operated continuously in the CASLEO astronomical complex since 2015. The detector modules of the

A new method for recording the parameters of sea waves, based on video recording of the length of vertically located strings, is considered. Cotton strings illuminated by an infrared searchlight glow brightly in their upper part, forming a clear edge at the interface. Measurements can be carried out at any time of the day at distances between the strings from units of millimeters to tens of centimeters

The possibilities of improving the measurement accuracy of fiber-optic sensors of absolute distances of the nanometer range using the spectral method of fiber-optic low-coherence interferometry have been investigated. The possibility of measuring the distance with an error of no more than \( \pm 15~\) nm in the range of 20–250 μm has been shown.

The acousto-optic method of summing the power of two lasers of the same type with modulation and intensity control is based on the simultaneous diffraction of two laser beams in one acousto-optic paratellurite crystal on one acoustic wave. For lasers with wavelengths from 400 to 1000 nm, the frequency range of acoustic waves is 30–5 MHz. The method is applicable to both continuous and pulsed lasers

A description of a procedure for selecting events during the absorption of stopped pions in thin targets is presented. This approach is based on the use of two monitor Si-detectors and a “live” target, which is also an Si-detector, as the last layers of the moderator. Setting the thresholds on monitor detectors and analyzing signals from a “live” target allow one to select pions with a residual range

During the approximation of kinetic energy transfer in collision cascades, a numerical estimate of the sputtering coefficient of the copper anode of a magnetron is considered. It has been shown that when a 1–10 keV ion beam is injected into a magnetron, the sputtering coefficient of the copper anode of the magnetron is three to six atoms per incident ion, which makes it possible to introduce and control

A radiation monitor based on a cast polystyrene scintillator with wavelength-shifting optical fibers is described, which has a large aperture; the dimensions of the active part of the detector are 100 × 200 × 5 cm. The monitor also includes a sensor for the presence of a monitored object and a television camera, united by a single control system. The monitor is designed to control transportation of

An apparatus for the rapid thermal extraction of Re radioisotopes from an irradiated tungsten target has been developed. Its operation was tested using a tungsten target pre-irradiated with deuterons on the U-150 cyclotron of the Kurchatov Institute. A description of the design of the apparatus and the principle of its operation are given. It has been shown that in one two-stage calcination–sublimation

Abstract—A technique for studying the resistance of IR-wavelength LEDs to the action of fast neutrons at the IRT-T reactor is described. A thermal neutron filter based on boron carbide and cadmium has been developed for the GEC-6 horizontal experimental channel of the IRT-T reactor. The identity of degradation processes in LEDs is shown when exposed to fast neutrons with pulsed (BARS-4 reactor) and

In electrostatic tandem charged particle accelerators, gas stripping targets are used to convert negative ions into positive ones. Partial ionization of the gas by ions leads to the formation of an undesirable beam of stripping gas ions in the accelerating channels. In this work, the current of a beam of argon ions produced in a tandem accelerator with vacuum insulation was measured by mass spectroscopy

Abstract— A multichannel hardware and software complex for studying electrochemical cells during charge–discharge cycling is described. The complex consists of 16 identical channel modules controlled by an on-board computer. Each channel is a four-band potentiostat/galvanostat that allows the performance of independent experiments. The modules can be hot-swapped during operation. Means are provided

Abstract A complex of four modern scintillation cosmic ray muon telescopes, which are part of the cosmic ray spectrograph after A.I. Kuzmin in Yakutsk, is described. Cosmic-ray detectors of this type are placed on the surface of the Earth, as well as in horizontal cuts that were specially dug in permafrost soils of a mine at depths of 7, 20, and 40 m of the water equivalent, and complement the previously

Abstract This study is an effort to comprehend the description of the vapour-liquid flows associated with the transformation of the phase, which may assist in determining mass, momentum and energy transfer within the interfacial region containing the steam and water. This study describes the development of a void fraction measurement sensory system, which is based on AC based electrodes, referred scientifically

Abstract— A Cherenkov proton-beam monitor has been investigated. Its electronic system consisting of a preamplifier and an amplifier of detector signals is described. The measured waveform is compared to the simulated monitor signals during proton detection. The relative variance of the photomultiplier-tube gain for single photoelectrons has been measured. Good agreement is observed between the results

Abstract— The design principles and the structural and circuitry solutions are described for digital computational synthesizers based on the method of direct digital synthesis of frequencies and signals. The structural and circuit diagrams of a digital computational synthesizer of complex wideband signals are presented. Using this synthesizer, it is possible to synthesize signals with amplitude, frequency

Abstract— A stimulation strategy has been developed for a new design of the cochlear implantation system that is being created by the MIPT. A model has been constructed that gives some idea of how a person with a cochlear implant perceives sound processed using this strategy. The strategy is assessed by comparing the sound obtained using the inverse transformation to the original sound. Many individual

Abstract The characteristics of an acoustooptic (AO) Bragg cell of two-color radiation as a differential spatial-frequency filter, in which the first diffraction order is the working one, have been investigated. It is shown that in a general case, it is impossible to provide two-dimensional image differentiation simultaneously at two wavelengths. A regime has been found that allows one to change from

Abstract The results of the development and the main characteristics of a new generation of semiconductor current switches (250 kA/25 kV/70 C) based on assemblies of series-connected reverse switched-on dynistors (RSDs) are presented. The methods for increasing the switched power and increasing the service life and reliability of RSD switches with maintenance of the previously accepted weight and size

Abstract A hardware–software complex has been designed for ipsilateral measurements of the acoustic reflex by determining the resonant frequency of the external auditory canal, which changes due to an involuntary contraction of the middle-ear muscles in response to high-intensity sounds. A modified two-microphone method was used to determine the resonance characteristics of the external auditory canal

Abstract The results of the development of the technology for the production of large surface-barrier semiconductor detectors and Al–αGe–pSi–Au heterojunction detectors (with diameters of 30–100 mm), as well as some data on the study of their electrophysical and radiometric characteristics, are presented. The block diagram of a radiometer of alpha radiation, the diagram of a microcontroller unit, and

A device for laser bioprinting is described, whose principle of operation is based on the transfer of a microscopic amount of gel with living systems from a donor substrate under the action of nanosecond laser pulses to arbitrary (acceptor) substrates. The use of a nanosecond pulsed laser source, a P-shaper lens, and a motorized telescopic system in the device makes it possible to automatically adjust

Neutron radiography using monochromatic neutron radiation makes it possible to visualize the diffraction contrast between different phases in a polycrystalline material due to the difference in the attenuation of the neutron beam intensity in these phases due to coherent neutron scattering. Although this method has already proven itself in studies of the phase distribution in steels, the literature

Abstract A generator of rectangular voltage pulses with an amplitude of ~30 kV, a rise time of ~1.5 µs, and a duration of up to 10 µs is described that contains a step-up pulse transformer, as well as thyristor switches with low and high operating voltages, which form, respectively, the front and fall of output pulses. The possibility of generating volume discharges with a frequency of 1 kHz in a barrier-type

Abstract— Two superconducting magnetic systems have been developed for an electron paramagnetic resonance spectrometer to produce a magnetic field with an induction of 7.0 T, a homogeneity of ~10–6 rel. units in a volume of 1 cm3, and a stability of ~10–7–10–8 rel. units/h in the central zone with a diameter as large as 100 mm. A solenoid, a scan coil, and coils for compensating axial and radial magnetic

Abstract A pulsed magnetron system that generates high-energy microwave pulses at a frequency of 100 Hz and an average power of 5 kW is described. A magnetron current pulse is generated using a circuit with 16 identical transistor units with an operating voltage of 800 V, which are connected in series to the primary winding of a high-voltage pulsed transformer with a transformation ratio of 5 during

Abstract A transistor generator of microsecond voltage pulses with an amplitude of up to 40 kV, which contains an unstabilized power source, a low-voltage capacitive energy storage device, and a step-up pulse transformer, is considered. It allows one to efficiently recover the energy reflected from a load upon a sharp change in its electrical resistance and provides a highly stable (with a spread below

The design of the spark gap of a pulsed high-current electron accelerator controlled by laser radiation is described. The results of testing the spark gap during operation as a primary switch in a high-current accelerator of the Radan type are presented. The developed spark gap provides an accelerator switch-on jitter of no worse than 0.3 ns.

Designs of hodoscopes of nuclear fragments based on quartz and scintillation plates with light pickup by silicon avalanche photodiodes are described. Hodoscopes are planned for use in the BM@N experiment for registration of heavy nuclear fragments near the axis of the heavy ion beam. The results of measurements of light yields in detector elements based on quartz and scintillation plates on the electron

Abstract A high-power generator based on small TB133-250-24 thyristors, which contains four thyristor modules with an operating voltage of 24 kV, is considered. The parameters of control pulses and protective circuits that provide low switching energy losses in series-connected thyristors and the absence of dangerous overvoltages upon their enabling are determined. The results of generator testing

Abstract An apparatus has been created at the Boreskov Institute of Catalysis, Siberian Branch, Russian Academy of Sciences (BIC SB RAS), to study the photochemical and thermal effects of infrared laser radiation on a two-phase gas–dust medium consisting of mixtures of light hydrocarbons and catalytically active nanoparticles. The apparatus includes reactors with gas flows from 10 to 1000 L/h and laser-radiation

An analysis of the operational parameters of an acousto-optic delay line (AODL) with direct detection, that is, the range of continuously controlled signal delay and the cutoff frequency of the passband, has been carried out. It is shown that the range of the smoothly controlled signal delay is limited by the maximum length of the photoelastic cell and the minimum velocity of propagation of the elastic

Abstract— Many algorithms that are capable of determining the indent area in automatic processing of optical images of imprints have found application in hardness measurements using the Vickers method. A robust interactive algorithm based on the maximum separation of color image components in the indentation area and an unstrained surface is described. The efficiency and stability of the presented

Abstract The study demonstrates use of TLD-K thermoluminescent detectors of ionizing radiation, which are made of a glass-based amorphous material, to measure high-density and high-intensity radiation, i.e., to doses of up to 1 kGy in the operating dosimetric peak at dose rates of up to 1011 Gy/s.

The results of testing a method for measuring the focal spot of bremsstrahlung using a “special lead lens” are presented. The test was performed on the basis of experimental dose distributions in the detector that were obtained during studies of the characteristics of bremsstrahlung radiation of a betatron at an acceleration energy of 4 MeV. The method was modeled using a set of collimators with different

Abstract— A technique is proposed for carrying out flight calibration of a photomultiplier tubes (PMTs) of the photodetector in the orbital TUS detector of ultra-high-energy cosmic rays in the absence of a calibration signal. The new technique consists in calculating two statistical characteristics of digitized signals from detected events (their mean value A and variance \(\sigma _{A}^{2}\)) and constructing

Abstract This paper describes the design solutions and characteristics of autonomous acoustic loggers and a brief description of the elements of the measuring hydrophysical complex (acoustic emitters, thermal strings, etc.), in which they are used. The technical capabilities of acoustic loggers allow one to quickly create various configurations of discrete antenna arrays and acoustic interferometers

Abstract— The dependence of the sputtering efficiency for a Mo mirror mock-up on the discharge power and the pressure of the working gas (Ar) has been investigated for three options of grounding of the discharge-cell elements in the plasma cleaning system. A gas discharge with a direct current or medium-frequency pulsed current is expected to be used to clean the entrance mirror of CXRS-edge (Active

Abstract As the space environment has deteriorated, it is necessary to monitor the impact events of space debris on orbiting spacecraft. The PVDF piezoelectric film release charge by the impact and its response is fast. The rest of the PVDF film can be re-measured. It can be used to detect space debris impacting spacecraft events, which has obvious advantages in real-time space detection and sensing

Abstract Two excitation methods based on 2D normal mode were proposed using two piezoelectric transducers (PZTs) with opposite phase and in-phase to excite the two dimensional normal modes of (1, 1) and (2, 1), respectively. The theoretical models of the excitation modes were deduced by the wave equation. An ultrasonic separator was built and the acoustic simulation of the ultrasonic excitation modes