Abstract Anomalously low ozone concentrations in the surface atmosphere in central Russia were recorded in spring of 2020. The increase in the ozone content usual for spring due to a seasonal increase in the temperature and light was followed by a monotonic decrease. The maximum daily values of surface ozone concentrations averaged over the month in April 2020 were three times less than the values

Abstract A new design and a new way of petal reflector deployment are proposed. New technical solutions will improve the accuracy of the reflecting surface of the telescope antenna in orbit and improve the quality of the instrument in the short-wavelength region of the spectrum.

Abstract In this paper, we present the form factor \(\gamma {\text{*}}\omega {{\pi }^{0}}\) measurement in the virtual photon mass range 1 GeV < \(\sqrt {{{q}^{2}}} \) < 2 GeV in the \({{e}^{ + }}{{e}^{ - }} \to \omega {{\pi }^{0}} \to {{\pi }^{ + }}{{\pi }^{ - }}{{\pi }^{0}}{{\pi }^{0}}\) process. Measurements are based on the data acquired by the SND detector at the VEPP-2000 \({{e}^{ + }}{{e}^{

Abstract Raman scattering (RS) spectra in lithium tantalate single crystals are studied at 180-degree scattering geometry in a wide frequency spectral range (50–2500 cm–1). RS intensity peaks corresponding to fundamental transverse (TO) and longitudinal (LO) polar optical modes of this crystal are recorded. It is found that the high-frequency spectral range (1300–2000 cm–1) contains RS intensity peaks

Abstract A technique for forming Au/SiO2 core/shell nanoparticles is developed. A long-wavelength shift of the extinction spectrum peak from 520 nm to 538 nm with increasing SiO2 shell thickness from a monolayer to 10 nm is established. It is experimentally shown that the anomalous spectral shift of the extinction spectrum peak of Au/SiO2 nanoparticle arrays from 538 nm to 720 nm, observed with increasing

Abstract It is found that one-electron states in thin semiconductor quantum rings based on semiconductor heterostructures satisfy special selection rules associated with the presence of two nonequivalent heteroboundaries. It is shown that the existence of a single stable one-electron level in the ring with preliminarily chosen characteristics (for a given heterostructure) can be achieved by selecting

Abstract Asymmetric resonances are detected in experimentally measured extinction spectra of gold and palladium alloy particles. To determine the effect of the particle chemical composition on the resonance shape, the extinction cross section of nanoparticle heptamer was numerically simulated as a function of the ratio of elements in the alloy.

Abstract The phenomenology of the simplest processes involving sgoldstino 260–1000 GeV in mass is studied. The effect of the sgoldstino–Higgs mixing on sgoldstino branching ratio and the cross-section of its production in proton–proton collisions is considered. The characteristic mode with the sgoldstino branching ratio of 1 : 2 : 1 was distinguished. It is interesting by the enhanced resonant Higgs

Abstract We develop a general formalism to study the reflection of radio waves, generated by ultra high energy cosmic ray events, from the Antarctic ice surface. Our formalism is based on plane wave decomposition of spherical waves and is applicable to the observations made by the ANITA detector. We find that our numerical result shows good agreement with the calibration data obtained by the High-Altitude

Abstract It is analytically shown that the total absorption of the hadron component of extensive air showers and the transition to the pure electromagnetic cascade cannot cause the observed sharp knee in the cosmic ray energy spectrum. This fact and the absence of proved nuclear models allow the conclusion that the knee origin is astrophysical.

Abstract Dynamics of the broad-area laser with time-periodic modulation of the pump parameter and external optical radiation injection is theoretically studied. It is shown that injection efficiently suppresses transverse instabilities resulting from pump modulation. The injected signal parameters at which transverse instabilities are efficiently suppressed are determined.

Abstract A search for the electroweak production of charginos and sleptons decaying into final states with two electrons and/or muons is presented. The analysis is based on 139 fb–1 of proton-proton collision data recorded by the ATLAS experiment at the Large Hadron Collider (LHC) at \(\sqrt s = 13\) TeV. Three R-parity-conserving scenarios are considered: the direct production of lightest chargino

Abstract The results of measurements of the dependence of the full width at half-maximum and the relative intensity of spectral peaks of parametric X-ray radiation (PXR) for various crystallographic planes on the grain size of a micrometer diamond powder are presented.

Abstract The temperature evolution of singly and doubly charged krypton ions in current sheets formed in magnetic fields with an X-line is studied. The electron temperature is determined; it is shown to be lower than the ion temperature by an order of magnitude, which points to different heating mechanisms of ion and electron components of current sheet plasma.

This study is devoted to the observation of the \(\Lambda _{b}^{0} \to J{\text{/}}\psi \Lambda \phi \) decay using proton-proton (pp) collision data collected at \(\sqrt s = 13\) TeV by the CMS experiment at the Large Hadron Collider in 2018, which corresponds to the integrated luminosity of 60fb–1. The branching fraction ratio \(\mathcal{B}(\Lambda _{b}^{0} \to J{\text{/}}\psi \Lambda \phi ){\tex

Abstract A method is suggested that allows the first measurement of the polarization of muons from τ-lepton decays at the Super charm-tau Factory. To measure the polarization, it is proposed to use muons decayed in flight in the drift chamber of the detector, when both tracks, mother and daughter, were reconstructed by the reconstruction program. The method is based on the correlation between the muon

Abstract Using the data acquired in the CMS experiment at the Large Hadron Collider (LHC) within 2016—2018, beautiful baryons decaying into \(\Lambda _{b}^{0}{{\pi }^{ + }}{{\pi }^{ - }}\) are studied. The existence of the \({{\Lambda }_{b}}{{(5912)}^{0}}\), \({{\Lambda }_{b}}{{(5920)}^{0}}\), \({{\Lambda }_{b}}{{(6146)}^{0}}\), and \({{\Lambda }_{b}}{{(6152)}^{0}}\) states is confirmed and their masses

This paper is dedicated to the experimental study of \(\Xi _{b}^{ - }\) baryons reconstruction using the data collected by the CMS experiment at the LHC in 2016–2018 in proton–proton collisions with center-of-mass energy \(\sqrt s = 13\) TeV, corresponding to an integrated luminosity of 140 fb–1. The obtained signal yield of \(\Xi _{b}^{ - } \to J{\text{/}}\psi {{\Xi }^{ - }}\) decay mode is more than

The effect of the induced longitudinal (along the toroidal magnetic field) electric field on the shape of soft X-ray spectra in the regime of electron cyclotron resonance (ECR) heating of plasma in the L-2M stellarator is considered. Causes of the appearance of non-Maxwellian two-slope spectra of soft X-rays measured in the axial ECR plasma heating regimes at the introduced microwave powers of 200–400 kW

Abstract A method for controlling the synchrotron beam intensity during proton irradiation of patients is proposed. The control is based on the installation of two precision “warm-liquid” pad chambers, one at the exit from the last scanning magnet and the other in front of the patient. The intensity density of the beam directed to the irradiated target using two pad chambers is measured. The measured

Abstract The porous silicon film surface region containing silver particles is studied by scanning electron microscopy and Raman spectroscopy. The porous silicon film is formed by metal-assisted etching of a single-crystal silicon substrate. It is found that the distribution of silver particles is controlled by the porous layer morphology. The formation of silver particles by chemical deposition results

Abstract We present specialized software for processing laser interferometry results, which make it possible to reliable data on the parameters of small-scale complex-structured plasma formations generated during the development of the nanosecond discharge in a gaseous medium. The software architecture, functional, processing options, and the results of physical studies, obtained with its use are described

Abstract Topological properties of the coauthorship graph are considered as applied to studies on physical sciences in Russia for 2012—2018. It was shown that key global properties of the coauthorship graph are formed by publications with a relatively small number of authors. Based on the analysis of characteristics of the distributions of degrees and weighted vertex degrees, it was shown that the

Abstract A new additional aspect of the analysis of the data of the OLYMPIA experiment on the search for nuclei of heavy cosmic ray components in olivine crystals from stony—iron meteorites is presented. Two groups of crystals with different charge spectra of recorded nuclei are detected. Possible causes of this phenomenon and its effect on the final spectrum are discussed.

Abstract The GaAs layer turn on Ge at a right angle in the substrate plane was studied by high-energy electron diffraction and transmission electron microscopy methods when growing GaAs/Ge/GaAs heterostructures using individual molecular-beam epitaxy systems for GaAs and Ge, with sample transfer through atmosphere.

Abstract The design of a linear ion Paul trap for quantum-logical operations on ultracold ions with high reliability is developed. The general requirements for the trap are presented, its parameters are optimized, and electric fields are numerically simulated.

Abstract The software for determining charged track parameters of the Spin Physics Detector (SPD) experiment on the future Nuclotron based Ion Collider fAcility (NICA) collider (JINR, Dubna) is presented along with the results obtained. The use of this program allows prompt simulations of various magnetic field configurations and the tracking system of the SPD experiment to determine the optimal structure

Abstract In observations of 2020 performed at the Large Phased Array radio telescope of the Lebedev Physical Institute, two new rotating transients were detected. Dispersion measures of the detected transients are DM = 21 and 35 pc/cm3, pulse half-widths are We = 18 and 35 ms for J1550+09 and J2047+13, respectively. The RRAT J2047+13 period was upper estimated as Р = 2.925. The study shows the existence

Abstract The linear coupling (transformation) of two wave modes in a peripheral layer of inhomogeneous plasma confined by a magnetic field is theoretically analyzed. This transformation is a cause of a decrease in the purity of the X-mode introduced into plasma, which is optimum for electron—cyclotron plasma heating at the second harmonic of gyrofrequency. It is shown that the mode purity defect in

Abstract An increase in the intensity of photoluminescence spectra of organic phosphor with terbium Tb3+ ions intruded into a 3D photonic crystal, i.e., SiO2 opal matrix, is established. The superluminescence effect is observed upon excitation at a wavelength of 369 nm at the 5D4–7F5 transition in Tb3+ ion in the green spectral region (λ = 545 nm). Lasing feasibilities in the composite opal matrix

Abstract The article is devoted to the technology of separating conglomerates of leukocyte cells in digital microscopy images of bone marrow preparations in the light range for determining the number of cells and automatic diagnosing. A special feature of the proposed method is the use of the principle of separating cell conglomerates based on abnormal points. The key points of the method: the determination

Abstract In this work we show an application of the N/D method to πK \(I = 1{\text{/}}2\) s-wave coupled channel scattering. Free parameters are constrained via matching to chiral perturbation theory. While we were able to find parameters that provide an excellent description of the scattering data, the corresponding amplitudes showed some unphysical properties like poles on the first sheet. By this

Abstract The objective of this research is to study the ejection of particles of a number of refractory metals from foils’ free surface when a shock wave is released on it. The choice of these metals is caused by that they are most promising materials for developing vacuum chambers of fusion reactors. The ejection of small (<1 μm) and large (to 10 μm) particles from the metal foil backside was detected

Abstract We present one example of the complete next-to-leading order potential of a \({{B}^{{( * )}}}\) – \({{\bar {B}}^{{( * )}}}\) system for the partial waves \({{J}^{{PC}}}\) = 0++, 1++, 1+–, 2++. The potential is ready to be used in a Lippmann-Schwinger equation. Then a fit to data for the exotic states Zb(10610) and Zb(10650) should reveal important information about the convergence of the chiral

Abstract This work is devoted to a comparative study of pharmacokinetic properties of complex compounds labeled with gallium-68 aminoglucose (68Ga-NODA-AG) or thioglucose (68Ga-NODA-TG) in BALB/c mice after intravenous administration. Statistical significance of activity accumulation in most organs and tissues was observed only at 5 min post-injection. At the following terms, these values didn’t have

Abstract A simplified model of thermally stimulated luminescence (TSL) and optically stimulated luminescence (OSL) kinetics is considered for the case of impeded carrier transport. A response function is obtained for the OSL with transport barrier, being of special interest for the extreme case of saturation mode (when the optical term in the model exceeds all other terms). In this case, the maximum

Abstract— Vectorial charge transfer upon pulsed laser excitation in three-layer Langmuir–Schäfer structures consisting of 100% photoactive molecules of porphyrin-fullerene dyad, phthalocyanine and polythiophene was studied. The behavior of the photovoltaic responses of the structures changed significantly upon selective optical excitation of monolayers. The mechanisms of the vectorial charge transfer

Abstract The production of a Z boson in association with a high-energy photon (γ) in proton-proton collisions has been studied at the Large Hadron Collider (LHC). These studies have been used to test the electroweak sector of the Standard Model and to search for new physics effects, such as potential couplings of Z bosons to photons. The Zγ production with the Z boson decaying into neutrinos has been

Abstract The dependences of potential energies E(R) for 48 states of the Ar*–He collision complex on the interatomic distance R were obtained using multiconfigurational methods of quantum mechanics with consideration of spin–orbit coupling with active space (6, 7). The values E(R ≥ 10 Å) are in good agreement, with an accuracy of 10–200 cm–1 (0.05–0.3%), with energies of Ar atom states.

Abstract For the first time to our knowledge, a number of Stokes and anti-Stokes lines with a shift in magnitude corresponding to stimulated Mandelstam—Brillouin scattering (SBS) lines in water are recorded in the SBS spectrum excited by nanosecond laser pulse focusing “under the free water surface.” In our opinion, this spectrum is caused by the nonlinear interaction of waves in the external cavity

Abstract The features of the photodissociation spectra of molecular \({\text{Kr}}_{2}^{ + }\) ions are studied in a wide range of gas temperatures. It is found that an increase in the gas temperature leads to a significant change in the frequency dependence of the photodissociation cross sections. A simple physical explanation of the temperature dependence of the cross sections is given.

Abstract It is proposed to use a new signal type fed to the single Langmuir probe to measure current—voltage characteristics. It is shown that such an approach makes it possible to increase the range of measured electron energy distribution functions.

Abstract For the first time to our knowledge, the Kane’s (k, p)-theory describing the electron mass renormalization in bulk semiconductors, is modified for thin (a few nanometers thick) quantum wires. It is shown that the longitudinal electron effective mass increases with quantum numbers of transverse motion. This leads to unique features of the electron spectrum in the wire under two conditions:

Abstract The effect of the coherence time of the semiconductor laser emitter incorporated in the most commonly used optoelectronic radio signal processor (OERSP) based on a multitapped optical delay circuit (ODC) on the transmission gain and signal-to-noise ratio at the device output is studied by computer simulation in a widely used optoelectronic CAD tool. It is found that efficient operation of

Abstract Experimental measurements of the Bragg peak depth by two methods: the air ionization chamber and the digital imaging detector (DIDE) for proton energies of 50, 100, and 170 MeV are compared. The principle of operation of a new detector type, i.e., the DIDE for measuring the energy release region of the proton beam passing through a water phantom is considered. The DIDE detector is a coordinate

Abstract–Numerical calculations and a comparative analysis of light extinction spectra of single silver nanoparticles shaped as sphere, rod, dumbbell, disk, and triangular prism are performed using the FDTD method. The strong dependence of the results for intensities and positions of maxima of localized plasmon resonance peaks on the geometrical shape of particles.

Abstract The all-fiber pulsed erbium laser with intracavity Mach–Zehnder modulator, operating in the Q-switching mode, is implemented. Stable modes of pulsed lasing at a wavelength of 1551 nm are demonstrated. The pulse repetition rate is varied in the range from 9.2 to 27.6 kHz. The pulse durations is varied in the range from 0.66 μs to 1.76 μs. Peak powers are varied in the range from 2.28 W to 0

Abstract Light absorption and scattering spectra of gold nanospheres coated with J-aggregates of TDBC dye are calculated. The effect of multipoles of different orders on the intensity distribution in absorption spectra due to the plasmon—exciton coupling of the nucleus and particle shell was established. The contributions of light absorption and scattering to the extinction cross section are determined

Abstract The results of cosmic-muon calibration of a shower lead-scintillation “sandwich”-type spectrometer of thickness 8.5X0, intended for operation in high-intensity photon and electron beams (~106 particles/s) with energies of 0.1–1.0 GeV are presented. It is found that the relative energy resolution of the spectrometer depends on the angle of cosmic muon entry into the spectrometer in the vertical

Abstract The DANSS detector, i.e., a scintillation detector with a sensitive volume of 1 m3, is installed at the Kalinin Nuclear Power Plant under the reactor on a moving stage. The distance from the detector center to the reactor core center can be varied from 10.9 to 12.9 m. The detector records about 5000 events of inverse beta decay per day with a background level from cosmic muons of the order

Abstract Two ultrastable laser systems for the clock transition spectroscopy in the strontium frequency standard are developed. The high stability of laser radiation frequency is provided by the active loop for frequency referencing to the Fabry–Perot reference cavity. The used cavities are made of glass with ultra-low thermal expansion coefficient and are 48 cm long which provides an extremely low

Abstract The problem of the description of the strong interaction of the InAs/GaAs exciton quantum dot (QD) grown by molecular-beam epitaxy with acoustic phonon and electron reservoirs is studied. A nonperturbative solution to the self-energy function of the exciton quantum dot is found. It is shown that these functions at temperatures higher than 10 K differ significantly from those obtained within

Abstract The relation between birefringence and dielectric susceptibility of helical nanostructures of ferroelectric liquid crystals in an electric field was studied experimentally and theoretically.

Abstract Topological properties of the co-authorship graph are considered as applied to the physical studies in Russia for 2012–2018. Objects of the study are two various weighted graphs; in the first one, edge weights correspond to the number of joint papers of two researchers; in the second one, weights are calculated by the technique accounting for the quality of journals in which joint papers are

Abstract The results of cosmic muon calibration of the extended quadrihedral NaI(Tl) spectrometer are presented. The signal amplitude and energy resolution of the spectrometer in the direction transverse to the spectrometer axis have complex dependences on the photomultiplier voltage and particle entrance point to the spectrometer. At a photomultiplier divider voltage U = 1150 ± 10 V, the region of

Abstract Methods for calculating the frequency of resonant oscillations of rectangular oscillators are considered. The operation of a micromechanical oscillator based on a silicon cantilever was theoretically studied in the problem of measuring the attached object mass. The dependence of mechanical parameters of an oscillator on the arrangement of an active (sensitive) region on the oscillator surface

Abstract The results of simulation of the dielectric resonator in the amplitude detector circuit with a Schottky diode in the range of 100–135 GHz are presented. It is shown that the use of Al2O3 hyperhemisphere on an insulating substrate makes it possible to increase the signal power in the antenna by a factor of 19 due to higher-order resonances in a narrow frequency band near 121 GHz. The resonator

Abstract Zinc selenide crystals doped with iron by high-temperature diffusion in zinc and argon atmospheres are studied by the two-photon confocal microscopy. The effect of the atmosphere on the spectra and spatial distribution of two-photon excited luminescence in the range from 425 to 725 nm is studied. It is shown that doping with zinc results in the absence of impurity-defect centers formed in

Abstract A dispersion relation for magnetoacoustic waves in partially ionized heat-releasing plasma in an external magnetic field is derived in a compact form. The increments of slow and fast modified magnetoacoustic waves are calculated in the case of isentropic instability; their strong dependence on the degree of ionization and frequency of ion—neutral collisions is showed.

Abstract The surface region of the CdS/por-Si/p-Si heterostructure in which the porous layer was formed by metal-assisted etching of the single-crystal p-Si substrate is studied by scanning electron microscopy and Raman spectroscopy methods. Experimental results of the CdS film morphology study are processed using two-dimensional detrended fluctuation analysis and average mutual information methods