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Terbium Organic Composition Photoluminescence in Globular Photonic Crystal Pores Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-12-30 V. S. Gorelik, A. N. Lobanov, M. T. Metlin, I. V. Taydakov
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
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Digital Microscopy Technologies: A Method for Constructing Incision Lines on Cell Conglomerate Images Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-12-30 V. G. Nikitaev, N. N. Tupitsyn, A. N. Pronichev, V. V. Dmitrieva, E. V. Polyakov, A. D. Samsonova, M. S. Grigoryeva, E. A. Druzhinina, A. D. Palladina
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
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N/D Method for πK Scattering as Part of MISP 2020 Proceeding Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-12-30 Frederic Noël, Leon von Detten, Christoph Hanhart
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
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Ejection of Refractory Metal Particles from the Foil Surface Exposed to Shock Waves Generated by High-Velocity Plasma Flows Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-12-30 V. Ya. Nikulin, P. V. Silin, E. N. Peregudova, I. V. Borovitskaya, V. N. Kolokoltsev, S. A. Maslyaev, L. I. Kobeleva, V. F. Degtyarev, A. I. Gaidar
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
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The Complete Next-to-Leading Order Potential of $${{{\mathbf{B}}}^{{( * )}}}{{{\mathbf{\bar {B}}}}^{{( * )}}} \to {{{\mathbf{B}}}^{{( * )}}}{{{\mathbf{\bar {B}}}}^{{( * )}}}$$ Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-12-30 Simon León Krug, Christoph Hanhart
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
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BEHAVIORAL FEATURES OF GALLIUM-68 RADIONUCLIDE INCORPORATED IN GLUCOSE DERIVATIVES IN LABORATORY ANIMALS Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-12-30 V. M. Petriev, V. K. Tishchenko, E. D. Stepchenkova, O. V. Fedorov, A.A. Fronya
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
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Thermally and Optically Stimulated Luminescence Kinetics with Impeded Carrier Transport Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-12-30 A. S. Selyukov, A. E. Primenko, T. A. Gardenina, M. I. Danilkin
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
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Peculiar Properties of Charge Transfer in a Multilayered Film Structure upon Selective Pulsed Photoexcitation Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-12-30 A. S. Alekseev, A. B. Ivanov, P. A. Saltykov, N. A. Tereschenko
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
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$${\mathbf{Z}}(\nu \bar {\nu })\gamma $$ Measurement and Neutral a TGC Limits at 13 TeV with the ATLAS Detector Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-11-23 Olympia Dartsi
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
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Calculation of Potential Energy Curves for Ar*–He Collision Complex Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-11-23 A. A. Pershin, P. A. Mikheyev, M. C. Heaven, A. M. Mebel
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.
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On the Nature of Processes Excited by Nanosecond Laser Pulses near the Water Surface Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-11-23 A. F. Bunkin, M. A. Davydov, S. M. Pershin, S. N. Fedorov
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
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Temperature Dependences of Photodissociation Cross Sections in Krypton Plasma Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-11-23 K. S. Kislov, A. A. Narits, V. S. Lebedev
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.
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Increasing the Measurement Range of Plasma Electron Parameters in the Single Langmuir Probe Method Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-11-23 S. N. Andreev, A. V. Bernatskiy, V. N. Ochkin
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.
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EFFECT OF SIZE QUANTIZATION SUBBAND CROSSING IN THIN QUANTUM WIRES Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-11-23 A. M. Mandel’, V. B. Oshurko, S. M. Pershin, S. G. Veselko, E. E. Karpova, A. A. Scharts, P. V. Aristarkhov
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:
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Effect of the Coherence Time of the Semiconductor Laser Emitter on the Quality of Radio Signal Processing in the Optoelectronic Delay-Line Processor Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-11-23 A. V. Alyoshin, M. E. Belkin, I. V. Gladyshev, A. P. Kanavin, A. S. Sigov, D. A. Fofanov
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
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MEASUREMENTS OF THE BRAGG PEAK DEPTH BY A PPC-40 IONIZATION CHAMBER AND A DIGITAL IMAGING DETECTOR Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-10-20 V. V. Siksin, A. E. Shemyakov
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
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Comparative Analysis of Optical Spectra of Plasmonic Nanoparticles of Different Geometrical Shapes Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-10-20 A. V. Mekshun, S. S. Moritaka, A. D. Kondorskii, V. S. Lebedev
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.
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ALL-FIBER ERBIUM LASER WITH INTRACAVITY MACH–ZEHNDER INTERFEROMETER Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-10-20 A. D. Zverev, V. A. Kamynin, V. G. Voronin, V. B. Tsvetkov
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
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Light Absorption and Scattering Spectra of Gold Nanospheres Coated with TDBC J-Aggregates Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-10-20 S. S. Moritaka, A. V. Mekshun, V. S. Lebedev, A. D. Kondorskii
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
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CALIBRATION OF A SHOWER LEAD-SCINTILLATION SPECTROMETER BY COSMIC RADIATION Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-10-20 V. I. Alekseev, V. A. Baskov, V. A. Dronov, A. I. L’vov, A. V. Koltsov, Yu. F. Krechetov, V. V. Polyansky, S. S. Sidorin
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
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Statistical Data Analysis in the DANSS Experiment Including Antineutrino Relative Count Rate Data as a Function of Distance Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-10-20 N. A. Skrobova
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
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Long ULE Cavities with Relative Fractional Frequency Drift Rate below 5 × 10 –16 /s for Laser Frequency Stabilization Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-10-20 N. O. Zhadnov, K. S. Kudeyarov, D. S. Kryuchkov, G. A. Vishnyakova, K. Yu. Khabarova, N. N. Kolachevsky
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
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Nonperturbative Effects in the Emission Spectra of Quantum Dots Interacting with Bosonic and Fermionic Reservoirs Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-10-02 R. Kh. Gainutdinov, D. G. Blum, A. Shirdelhavar, A. A. Mutygullina
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
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ELECTRICALLY CONTROLLED BIREFRINGENCE AND DIELECTRIC SUSCEPTIBILITY OF HELICAL NANOSTRUCTURES OF FERROELECTRIC LIQUID CRYSTALS Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-10-02 T. P. Tkachenko, A. V. Kuznetsov, E. P. Pozhidaev
Abstract The relation between birefringence and dielectric susceptibility of helical nanostructures of ferroelectric liquid crystals in an electric field was studied experimentally and theoretically.
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Topology of the Co-Authorship Graph in the Field of Physics in Russia Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-10-02 O. I. Ivanov, A. M. Kovalenko, A. V. Kolobov, V. V. Koroleva, A. V. Leonidov, E. E. Serebryannikova
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
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CALIBRATION OF THE EXTENDED QUADRIHEDRAL NaI(Tl) SPECTROMETER BY COSMIC MUONS Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-10-02 V. A. Baskov, B. B. Govorkov, V. V. Polyansky
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
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Calculation of Resonant Oscillations of a Micromechanical oscillator with an Attached Mass Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-10-02 T. A. Efimov, R. V. Romashko, E. A. Rassolov, I. N. Zavestovskaya
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
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Subterahertz Radiation Concentrator Based on a Hyperhemisphere-Shaped Dielectric Resonator Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-10-02 D. V. Storozhenko, A. V. Nepomnyashchii, T. A. Efimov, R. V. Romashko, Yu. N. Kulchin, I. N. Zavestovskaya
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
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Effect of Zinc Atmosphere upon Doping ZnSe : Fe Crystals on the Composition and Distribution of Impurity-Defect Centers Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-10-02 A. A. Gladilin, S. I. Chentsov, S. A. Mironov, O. V. Uvarov, N. N. Ilichev, M. I. Studenikin, E. M. Gavrischuk, N. A. Timofeeva, D. F. Aminev, V. P. Kalinushkin
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
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Magnetoacoustic Waves in Partially Ionized Two-Fluid Heat-Releasing Plasma Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-10-02 N. E. Molevich, S. Yu. Pichugin, D. S. Ryashchikov
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.
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Structural Features of the Surface Region of the CdS/por-Si/p-Si Heterostructure with a Porous Silicon Film Formed by Metal-Assisted Chemical Etching Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-09-09 N. N. Melnik, V. V. Tregulov, N. B. Rybin, N. V. Rybina
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
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Runaway Electrons Emitted by Electron Avalanches in Nanosecond Discharges in Air Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-09-09 G. A. Mesyats, N. M. Zubarev, I. V. Vasenina
Abstract Nanosecond electric discharges in atmospheric air at high overvoltages are considered. Plasma channels and diffuse plasma glow simultaneously exist in these discharges. Channels are created by subnanosecond streamers formed in the cathode region. Diffuse glow is caused by runaway electrons emitted by electron avalanche heads. The necessary electric field enhancement is created due to the plasma
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Behavior of gallium-68 incorporated in NODA aminoglucose in laboratory animals with various pathological processes Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-09-09 V. K. Tishchenko, V. M. Petriev, A. V. Fedorova, T. Yu. Ekatova, I. N. Zavestovskaya
Abstract Comparative results of the study of the biological distribution of 68Ga incorporated in NODA aminoglucose in mice organs and tissues with the experimental model of malignant tumor and aseptic inflammation are presented. It is revealed that pathological conditions have no significant effect on the 68Ga-NODA aminoglucose behavior after intravenous administration. The dynamics of activity accumulation
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Characteristics of the Secondary Electron Calibration Beam of the S-25R “Pakhra” Accelerator Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-09-09 V. I. Alekseev, V. A. Baskov, V. A. Dronov, A. I. L’vov, Yu. F. Krechetov, A. V. Koltsov, V. V. Polyansky, S. S. Sidorin
Abstract Characteristics of the calibration quasi-monochromatic secondary electron beam of the S-25R “Pakhra” accelerator of the Lebedev Physical Institute, based on the SP-57 magnet are presented. At the electron beam energy of 280 MeV, a collimator diameter in front of trigger counters of 3 mm, and a copper converter thickness of 1–3 mm, the relative energy resolution and beam intensity are δ = 2
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Study of Neutrons Produced in the Interaction of Muon Antineutrinos in the ND280 near Neutrino Detector of the T2K Experiment Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-09-09 A. A. Shaikina
Abstract Neutrons produced during scattering of muon antineutrinos through charged currents in the ND280 near neutrino detector of the T2K experiment are studied. Based on Monte-Carlo simulations of the beam of accelerator antineutrinos with an energy of ~0.6 GeV, the kinematics of the quasi-elastic interaction is reconstructed. Energy and angular distributions of neutrons are obtained, their detection
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Structural Features and General Morphology of Copper, Zinc, Zirconium, Molybdenum, Tungsten, and Vanadium Oxide Nanostructures Synthesized by Laser Ablation Method in Water Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-09-09 T. I. Borodina, G. E. Val’yano, V. T. Karpukhin, M. M. Malikov, M. A. Kazaryan
Abstract Nanostructures of oxides of 3d—5d transient metals: copper, zinc, zirconium, molybdenum, tungsten, and vanadium are synthesized by laser ablation of pure metals in water. Electro-optical and X-ray studies showed that the layered material composing nanostructures is mostly in an amorphous state and apparently consists of molecular clusters no larger than 1—2 nm. The structures of studied oxides
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Luminescence Degradation Mechanisms in CdS/ZnSe Colloidal Nanocrystals Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-07-27 M. S. Zabolotskii; A. V. Katsaba; S. A. Ambrozevich; A. G. Vitukhnovskii; R. B. Vasil’ev
AbstractThe results of the study of one-photon processes of optically induced degradation of photoluminescence intensity of CdS/ZnSe nanocrystals are presented, and mechanisms of this degradation are determined. It is shown that the nanocrystal photodegradation process consists of three components. The first degradation component is caused by Auger recombination activation in photoinduced hole trapping
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Effect of Neutral Bremsstrahlung on the Operation of Two-Phase Argon Detectors Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-07-27 A. E. Bondar; E. O. Borisova; A. F. Buzulutskov; V. V. Nosov; V. P. Oleynikov; A. V. Sokolov; E. A. Frolov
AbstractTwo-phase noble liquid detectors are widely used in experiments for dark matter search. Ionization signals caused by particle scattering in a noble-gas liquid are commonly recorded using the effect of proportional electroluminescence in the gas phase. In addition to the standard electroluminescence mechanism based on vacuum ultraviolet emission of noble gas excimers, the mechanism of electron
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Gamma Spectrometry System for Decommissioning Nuclear Facilities Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-07-27 S. E. Ulin; V. V. Dmitrenko; K. F. Vlasik; V. M. Grachev; R. R. Egorov; K. V. Krivova; A. I. Madzhidov; Z. M. Uteshev; I. V. Chernysheva; A. E. Shustov
AbstractThe structure of gamma spectrometry systems for decommissioning nuclear facilities is considered. Physicotechnical characteristics of a xenon gamma spectrometer being a main device for measuring gamma spectra of analyzed objects and determining their activity are presented. The practicability of xenon gamma spectrometers in decommissioning nuclear facilities is shown. The data obtained using
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Comparison of Techniques for Measuring the Gain of Weak Signals of Solid-State Diode-Pumped Laser Gain Modules in a Nd:YAG Active Medium Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-07-27 D. D. Chesalin; V. Kh. Bagdasarov; V. V. Bukin; T. V. Dolmatov; B. D. Ovcharenko
AbstractIt is shown that direct measurements of the gain of weak signals of an active element irradiated by a probe laser can give a result much lower than that measured by the lasing threshold. A possible cause of such disagreement is discussed.
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Dust-Acoustic Soliton in a Plasma with Relativistic Electrons Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-07-27 D. N. Gabyshev; A. A. Rukhadze
AbstractThe one-dimensional non-relativistic dust-acoustic soliton is considered in the model of plasma with cold positively charged dust particles, warm ions, and relativistic thermal electrons (taking into account trapping of the latter). The influence of an increase in the electron temperature is shown.
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Study of $${\text{B}}_{{{\text{s}}2}}^{ * }$$ (5840) 0 and B s1 (5830) 0 Mesons in the CMS Experiment Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-07-27 S. Polikarpov
AbstractUsing the data collected by the CMS experiment at the Large Hadron Collider in collisions of protons with a center-of-mass energy of 8 TeV, excited P-wave states \({\text{B}}_{{{\text{s}}2}}^{ * }{{(5840)}^{0}}\) and Bs1(5830)0 of the \({\text{B}}_{{\text{s}}}^{0}\) meson are studied. The decay \({\text{B}}_{{{\text{s}}2}}^{ * }{{(5840)}^{0}} \to {{{\text{B}}}^{0}}{\text{K}}_{{\text{s}}}^{0}\)
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Effect of Electron Beam Excitation Pulses on the Lasing Threshold of the Laser Semiconductor Target Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-07-27 A. S. Nasibov; V. G. Bagramov; K. V. Berezhnoi; Yu. V. Plokhinskii; I. D. Tasmagulov
AbstractThe dependence of the threshold intensity of the electron beam (EB) on the pulse shape and duration upon lasing excitation in a laser semiconductor target (ST) is considered. It is shown that a minimum EB threshold intensity can be reached before the pulse end in the case of sinusoidal pulses. The possibility of decreasing the EB threshold intensity and laser radiation duration under the ST
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NUCLEAR STRUCTURE CORRECTIONS IN THE HYPERFINE STRUCTURE OF P -STATES IN LIGHT MUONIC IONS Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-07-06 A. P. Martynenko; F. A. Martynenko; O. S. Sukhorukova
AbstractThe effects of the nuclear structure from two-photon exchange amplitudes in the hyperfine structure of P-states in muonic ions of lithium, beryllium, and boron are calculated. The operator of particle interaction in momentum space is constructed using the method of projection operators on states with certain total momenta of the atom F and muon J. Corrections to the nucleus structure are expressed
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Optical Coherence Microscopy Сombined with Optical Tweezers for Studying Cellular Mechanics Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-07-06 M. A. Sirotin; M. N. Romodina; E. V. Lyubin; I. V. Soboleva; A. A. Fedyanin
Abstract—A method combining phase-sensitive optical coherence microscopy (OCM) and optical tweezers for studying mechanical properties of microobjects including biological cells is implemented. The process of microbead trapping was studied using the developed method. The response of the red blood cell (dyscocyte and spherocyte) membrane to the optical tweezer excitation is measured.
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ON THE ACCURACY OF AVAILABLE WAVENUMBER VALUES FOR ELECTRONIC-VIBRO-ROTATIONAL TRANSITIONS OF THE H 2 MOLECULE Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-07-06 O. O. Diachkova; B. P. Lavrov; A. S. Mikhailov; V. A. Riazantceva
AbstractAll published to date experimental wavenumber values (ν, cm–1) for electronic-vibro-rotational transitions of the H2 molecule are statistically analyzed in the vacuum wavelength range 1/ν = 600—610 nm. It is shown that a direct comparison of all datasets of various authors is blocked by the absence of deconvolving of measured spectra, blending of neighbor lines (an overlap of their profiles)
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Technique for Separating Electrons in a Wide PAMELA Calorimeter Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-07-06 A. A. Kvashnin; A. N. Kvashnin
AbstractIn this study, to separate electron- and proton-induced cascades in the calorimeter at energies above 300 GeV, it is proposed to use the difference in the cascade absorption lengths of these particles. The applicability of the proposed criterion to reject hadron events in selecting electron-induced cascades in the “PAMELA” calorimeter is studied. The efficiency and applicability limits of this
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Recording of Hydroacoustic Signals Using a Fiber-Optic Accelerometer Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-07-06 O. T. Kamenev; Yu. S. Petrov; A. A. Podlesnykh; V. A. Kolchinskii; I. N. Zavestovskaya; Yu. N. Kulchin; R. V. Romashko
AbstractA prototype of a mobile fiber-optic accelerometer in which a multiturn optomechanical transducer placed in a fiber-optic Mach–Zehnder interferometer interferometer arm is used as a sensitive element is developed and studied. Passive phase demodulation using a fiber-optic splitter 3 × 3 maintains stable accelerometer operation in the case of a temperature drift of an operating point. The detectability
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ABERRATIONAL PATTERN DURING THE SELF-ACTION OF THE ТЕМ 01 MODE OF LIGHT RADIATION IN NEMATIC LIQUID CRYSTALS Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-07-06 I. A. Budagovsky; A. S. Zolot’ko; A. A. Kuznetsov; M. P. Smayev; S. A. Shvetsov; A. Yu. Bobrovsky; N. I. Boiko; V. P. Shibayev
Abstract—The properties of the aberrational pattern resulting from the self-action of the light radiation mode TEM01 in liquid-crystal systems are studied. It is found that the interference of light rays corresponding to two peaks of intensity and nonlinear phase shift leads to the formation of a system of fringes in the Fraunhofer region; their angular period is controlled by the distance between
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Study of Single-Electron Spectrum of GaAs/AlGaAs Heterostructure for Mid-IR Photodetectors via Low-Temperature Luminescence Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-06-11 D. A. Litvinov; D. A. Pashkeev; L. N. Grigoreva; S. A. Kolosov; D. F. Aminev
AbstractBy measuring low-temperature photoluminescence, we demonstrated the role of interface blurring and the introduction of background impurities in the formation of the single-electron spectrum of GaAs/AlxGa1–xAs quantum well heterostructures used to fabricate mid-IR photodetectors. Background impurities, having a noticeable effect on the emission spectrum of quantum wells, do not affect their
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Drift Characteristics of Metal Ions in Helium in an External Electric Field Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-06-11 S. A. Maiorov; G. B. Ragimkhanov; Z. R. Khalikova
AbstractThe results of Monte Carlo calculations of the drift characteristics of metal ions (Li, Be, Al, Fe, Cu, W, Hg, and Au) in a constant uniform electric field 1 < E/N < 1000 Td in helium are presented. The dependences of the mobility, longitudinal and transverse diffusion coefficients, and mean kinetic energy of ions, as well as their longitudinal and transverse temperatures, on the electric field
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Observation of Phase Transitions in an Electron–Hole System Associated with Dislocation Cores in Cadmium Telluride Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-06-11 V. S. Krivobok; S. N. Nikolaev; V. S. Bagaev; E. E. Onishchenko; S. I. Chentsov; M. A. Chernopitssky; A. I. Sharkov
Abstract—Evolution of the fine structure of dislocation microphotoluminescence lines in cadmium telluride with a decrease in the optical-excitation power density has been demonstrated at low (5 K) temperatures. The character of this evolution for each of the three bands under investigation (Y1 (~1.47 eV), Y2 (~1.49 eV), and Y3 (~1.51 eV)) indicates the existence of a transition from electron–hole plasma
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Vicinal Growth as a Possible Structural Source of the Nematic Superconductivity in Sr x Bi 2 Se 3 Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-06-11 V. P. Martovitskii; Yu. G. Selivanov; A. Yu. Kuntsevich
AbstractThe structure of the layered SrxBi2Se3 crystals characterized by the nematic superconductivity has been studied. It is shown that the higher the degree of the superconducting and structural nematicity, the stronger the deviation of the block boundary orientation from the crystal c axis. This indicates that the block grows at an angle to the basal planes, rather than along them. This growth
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Detector Effects on the Response of a Highly Granular Hadron Calorimeter to Single Hadrons Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-06-11 S. Korpachev; M. Chadeeva
Abstract—In the detectors currently being developed for experiments on the next-generation lepton colliders, highly granular calorimeters are to be used. In particular, the hadron calorimeter is planned to be assembled from scintillation cells with direct readout of light by silicon photomultipliers. According to the results of experimental measurements of the light collection in a cell developed for
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Estimation of the DANSS Experiment Sensitivity to Neutrino Oscillations Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-06-11 N. A. Skrobova
Abstract—DANSS is a highly segmented scintillator detector with a sensitive volume of 1 m3. The detector is located at the Kalinin Nuclear Power Plant under the reactor core on a moving platform. The distance from the detector center to the reactor center is varied from 10.7 to 12.7 m. The inverse beta decay reaction is used to detect antineutrino. DANSS detects about 5000 events per day with the background
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Tablet Coating Thickness Measurements by Combined Raman Spectrometry and Laser Induced Breakdown Spectrometry Techniques Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-05-19 V. N. Lednev; P. A. Sdvizhenskii; S. M. Pershin
AbstractFor the first time, pharmaceutical tablet coating thickness is measured by combined Raman spectrometry (RS) and laser induced breakdown spectrometry (LIBS) techniques. Measurements by two methods (RS and LIBS) are performed during a single pump lamp flash of a pulsed Nd:YAG laser in the double pulse lasing mode. This approach combining a probe laser pulse (RS) followed by an ablating laser
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Viscoelastic Nanocomposites of Wormlike Micelles of Surfactant and Aluminosilicate Clay Nanoplates Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-05-19 V. S. Molchanov; S. A. Shvetsov; O. E. Philippova
AbstractViscoelastic nanocomposites based on a matrix of semidilute aqueous solutions of entangled wormlike (polymer-like) micelles of a cationic surfactant and aluminosilicate nanoplates of montmorillonite clay, efficiently acting as crosslinks, were prepared and studied. The produced materials represent a new type of a self-assembling nanocomposite system. The results of changes in viscoelastic properties
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Kinetics of Reactions of 1- and 2‑Naphthyl with Propyne and Allene Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-05-19 A. D. Oleinikov; A. M. Mebel; V. N. Azyazov
Abstract—Quantum-mechanical ab initio calculations are applied to study the growth mechanism of polycyclic aromatic hydrocarbons via reactions of 1- and 2‑naphthyl with propyne (methylacetylene) and allene (1,2‑propadiene). It was shown that stabilized isomers С13Н11 are mostly formed at temperatures <1000 K. At temperatures above 1000 K, the yield of bimolecular three-ring products C13H10 + H and
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Geomagnetic Storms and Forbush-Decreases Related to Single and Complex Transient Structures of Solar Wind Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-05-19 D. G. Rodkin; V. A. Slemzin; Yu. S. Shugay
AbstractThe geoeffectiveness of single and complex transient structures of the solar wind (SW), formed by coronal mass ejections (CMEs) and associated Forbush decreases (FDs) in the cosmic ray flux is considered. By the example of the period of 2010–2011, it is shown that complex SW structures resulting from the interaction of CMEs with high-speed streams from coronal holes or with other CMEs in the
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Prototype of a Meter-Wavelength Radio Telescope with Wide Field-of-View Bull. Lebedev Phys. Inst. (IF 0.477) Pub Date : 2020-05-19 R. D. Dagkesamanskii; A. V. Veselovskii; I. M. Zheleznykh; B. K. Izvekov; A. V. Kovalenko; A. M. Lapik; M. V. Mordovskoi
AbstractThe scheme and components of a wide field-of-view meter-wavelength radio telescope prototype developed based on an antenna array consisting of 128 dipoles is described. The operating frequency range is 38–74 MHz. Main parameters of the future prototype are presented and versions of its development are discussed.