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Issue 3, 2017

Physics of nuclei and elementary particles

The Way to Superheavy Elements

The Way to Superheavy Elements

B.S. Ishkhanov$^{1,2}$, T.Yu. Tretyakova$^2$

Moscow University Physics Bulletin 2017. 72. N 3. P. 203

This review is devoted to the studies of heavy and superheavy elements and the methods of their synthesis and identification. Special attention is paid to the latest discoveries in the area of superheavy elements with $Z =107-112$ in cold fusion reactions and $Z = 113-118$ in reactions between $^{48}$Ca and actinides.

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Optics and spectroscopy. Laser physics

Light Interference and the Absence of Definite Values of Measured Quantities a Priori

Light Interference and the Absence of Definite Values of Measured Quantities a Priori

A. V. Belinsky

Moscow University Physics Bulletin 2017. 72. N 3. P. 224

The peculiarities of the behavior of photons in various experimental situations are considered. Variants of double-beam interference of a single photon and the possibility of forming a standing wave by this photon are analyzed; three-beam interference is also discussed. The effects observed in this case prove the absence of particular values of the measured quantities up to the moment of measurement; in the latter case, the number of photons in the field does not a priori have a certain value, in spite of the fact that the system is in the energy state. An experiment is also considered that proves the absence of a certain phase and the phase difference of photons in the Fock state, which makes it possible to treat different types of theories of hidden parameters, including nonlocal ones, more critically.

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Physics of Earth, atmosphere, and hydrosphere

Predicting Rogue Waves

Predicting Rogue Waves

A.V. Slunyaev

Moscow University Physics Bulletin 2017. 72. N 3. P. 236

Observational data regarding anomalously high waves on the sea’s surface (freak or rogue waves) are reviewed. The objectives of the research are identified, and the difficulties encountered are noted. The main physical mechanisms employed in explaining rogue waves are listed, and possible approaches to predicting marine hazards are discussed. Principles for ongoing short-term forecasting of extreme waves (within tens of wave periods or wavelengths) are proposed. Some preliminary results are presented.

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Physics of nuclei and elementary particles

On Neutrino Masses and Source of Dark Energy

On Neutrino Masses and Source of Dark Energy

Salah Eddine ENNADIFI

Moscow University Physics Bulletin 2017. 72. N 3. P. 271

We propose a Higgs-extended model in which neutrinos naturally acquire tiny Majorana masses as constrained by the electroweak precision data, while the associated pseudo Nambu-Goldstone boson serves as an attractive candidate for dark enegy.

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Photon beam softening coefficients evaluation for a 6 MV photon beam for an aluminum slab: Monte Carlo study using BEAMnrc code, DOSXYZnrc code and BEAMDP code

Photon beam softening coefficients evaluation for a 6 MV photon beam for an aluminum slab: Monte Carlo study using BEAMnrc code, DOSXYZnrc code and BEAMDP code

Mohamed BENCHEIKH, Abdelmajid MAGHNOUJ and Jaouad TAJMOUATI

Moscow University Physics Bulletin 2017. 72. N 3. P. 263

Determination and understanding the photon beam attenuation by the photon beam modifier and the radiation beam softening for clinical use is more important part of material study for the beam modifier enhancements and the linac improvements. A Monte Carlo model was used to simulate 6 MV photon beams from a Varian Clinac 2100 accelerator with the flattening filter and the later was replaced by the aluminum slab with variable thickness. The Monte Carlo geometry was validated by a gamma index acceptance rate of 99% in PDD and 98% in dose profiles, the gamma criteria was 3% for dose difference and 3mm for distance to agreement. The purpose was to investigate aluminum material attenuation and beam softening coefficients as a function of the inserted aluminum slab thickness and of off-axis distance. The attenuation and beam softening coefficients were not identical for the same off-axis distance and they varied as a function of aluminum slab thickness. The results of our study were shown that the beam softening coefficients were varied with thickness beam modifier materiel used for beam softening and the off-axis distance inside the irradiation field. Thereafter, the softening coefficient a1 have a maximum of 2,5$\times 10^{-1}$ cm$^{-1}$ for the aluminum slab thickness of 1 mm, 1,4$\times 10^{-1}$ cm$^{-1}$ for the aluminum slab thickness of 1,5 mm and 4,47$\times 10^{-2}$ cm$^{-1}$ for the aluminum slab thickness of 2 mm. The maximum of the second softening coefficient a2 was 1,02$\times 10^{-2}$ cm$^{-2}$ for the aluminum slab thickness of 1 mm, was 1,92$\times 10^{-2}$ cm$^{-2}$ for the aluminum slab thickness of 1,5 mm and was 1,93$\times 10^{-2}$ cm$^{-2}$ for the aluminum slab thickness of 2 mm.

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Neutrinos and Probes of High Scale Physics

Neutrinos and Probes of High Scale Physics

R. Ahl Laamara$^{1,2}$, K. Douhou$^1$, M.Drissi El Bouzaidi$^1$, S-E Ennadifi$^1$

Moscow University Physics Bulletin 2017. 72. N 3. P. 257

Abstract—In light of the theoretical and experimental developments in the neutrino sector and their importance, we study its connection with the new physics above the electroweak scale. In particular, by considering the neutrino oscillations with the possible effective mass, we investigate, according to the experimental data, the scale as well as the signature of the underlying new physics beyond the SM.

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Theoretical and mathematical physics

Superconductivity in Chiral-Asymmetric Matter within the (2 + 1)-Dimensional Four-Fermion Model

Superconductivity in Chiral-Asymmetric Matter within the (2 + 1)-Dimensional Four-Fermion Model

V. Zhukovsky$^1$, K. Klimenko$^2$, T. Khunjua$^3$

Moscow University Physics Bulletin 2017. 72. N 3. P. 250

The phase structure of chiral-asymmetric matter has been studied within the (2 + 1)-dimensional quantum-field theory with the fermion–antifermion and fermion–fermion (or superconducting) channels of four-fermion interaction. For this purpose, the model takes both the chemical potential of the number of particles $\mu$ and the chiral chemical potential $\mu_5$ conjugated to the difference between the numbers of right and left fermions into account. A series of phase diagrams was plotted for different chemical potentials. It is shown that the chemical potential $\mu$ promotes the appearance of a superconducting phase, while an increase in the chemical potential $\mu_5$ suppresses the effect of the chemical potential $\mu$ on a system. The results of this study may be of interest for high-energy physics, condensed matter physics and, in particular, graphene physics.

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Optics and spectroscopy. Laser physics

An Error Self-Compensation Mechanism for Deposition of Optical Coatings with Broadband Optical Monitoring

An Error Self-Compensation Mechanism for Deposition of Optical Coatings with Broadband Optical Monitoring

A.V.Tikhonravov$^1$, I.V. Kochikov$^1$, M.K.Trubetskov$^2$, S.A. Sharapova$^1$, V.G. Zhupanov$^3$, A.G. Yagola$^4$

Moscow University Physics Bulletin 2017. 72. N 3. P. 274

An error self-compensation mechanism is investigated for use during the deposition of optical coatings with broadband optical monitoring. The correlation of thickness errors caused by monitoring procedure is mathematically described. It is shown that this correlation of errors may result in the effect of selfcompensation of errors.

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Condensed matter physics

A Method of Dopant Electron Energy Spectrum Parameterization for Calculation of Single-Electron Nanodevices

A Method of Dopant Electron Energy Spectrum Parameterization for Calculation of Single-Electron Nanodevices

V. V. Shorokhov

Moscow University Physics Bulletin 2017. 72. N 3. P. 279

Solitary dopants in semiconductors and dielectrics that possess stable electron structures and interesting physical properties may be used as building blocks of quantum computers and sensor systems that operate based on new physical principles. This study proposes a phenomenological method of parameterization for a single-particle energy spectrum of dopant valence electrons in crystalline semiconductors and dielectrics that takes electron–electron interactions into account. It is proposed to take electron–electron interactions in the framework of the outer electron shell model into account. The proposed method is applied to construct the procedure for the determination of the effective dopant outer shell capacity and the method for calculation of the tunneling current in a single-electron device with one or several active dopants–charge centers.

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An Optimization Method for the Calculation of Hamiltonian Matrix Elements for Josephson Flux Qubits

An Optimization Method for the Calculation of Hamiltonian Matrix Elements for Josephson Flux Qubits

A. V. Kuznetsov$^1$, N. V. Klenov$^{1,2,3}$

Moscow University Physics Bulletin 2017. 72. N 3. P. 287

This work aims to describe the method of analytical calculation of an orthonormalized basis of states of the Josephson flux quantum bits (qubits) using a two-level approximation under the condition that the potential energy of the system is a combination of two potential wells separated by a tunnel barrier. For illustration, the calculation results in the case of the well-known three- and four-junction flux qubits, as well as promising silent qubits, are presented.

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Chemical physics, physical kinetics, and plasma physics

The Electron Temperature in the Plasma of a DC Discharge Created in a Supersonic Airflow

The Electron Temperature in the Plasma of a DC Discharge Created in a Supersonic Airflow

V.M.Shibkov, L.V.Shibkova, A.A.Logunov

Moscow University Physics Bulletin 2017. 72. N 3. P. 294

The plasma parameters of a pulsating DC discharge created in a supersonic airflow with a Mach number of M = 2 are determined. It is revealed that along with the intense bands of CN and the molecular nitrogen ion, as well as the spectral lines of atomic oxygen, nitrogen, hydrogen and copper, an intense continuous spectrum is observed in the spectrum of the gas-discharge plasma radiation, which is caused by the deceleration of electrons on ions. The dependences of the electron temperature on the discharge current and longitudinal coordinates are determined. It was revealed that the studied plasma is nonequilibrium, with the electron temperature being much higher than the gas temperature.

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Biophysics and medical physics

Electrons and Proton Transfer in Chloroplasts In Silico: 1. The Effect of Topological Factors on Energy Coupling in Chloroplasts with a Nonuniform Distribution of Protein Complexes

Electrons and Proton Transfer in Chloroplasts In Silico: 1. The Effect of Topological Factors on Energy Coupling in Chloroplasts with a Nonuniform Distribution of Protein Complexes

A.V. Vershubskii, A.N. Tikhonov

Moscow University Physics Bulletin 2017. 72. N 3. P. 301

This paper presents a theoretical study of the effects of topological factors (density of thylakoid packing in grana) on the efficiency of energy coupling in chloroplasts. The study is based on a mathematical model of electron and proton transport processes coupled to ATP synthesis in chloroplasts. The model was developed by the authors earlier, and the nonuniform distribution of electron transport and ATP synthase complexes in the membranes of granal and intergranal thylakoids was taken into account in the model. The results of numerical experiments enabled the analysis of the distribution of lateral profiles of the transmembrane pH difference and the concentrations of mobile plastoquinone and plastocyanin electron transporters in granal and intergranal thylakoids and the dependence of this distribution on the metabolic state of class B chloroplasts (photosynthetic control state or the conditions of intensive ATP synthesis). Moreover, the influence of topological factors (the density of thylakoid packing in grana and the degree of thylakoid swelling) that affect the rate of diffusion of protons and mobile electron carriers in the intrathylakoid space and in the interthylakoidal gap was investigated. The results of numerical experiments that involved the variation of geometric parameters of the system revealed the influence of thylakoid thickness and the distance between the granal thylakoids on the lateral pH profiles inside the thylakoids (pH$_i$) and in the interthylakoidal gap (pH$_0$). Acidification of the intrathylakoid space characterized by the pH$_i$ value increased concomitantly to the increase of the width of the interthylakoidal gap lo and decreased concomitantly to the increase of the width of the intrathylakoidal space l$_i$.

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Shannon Entropy in the Research on Stationary Regimes and the Evolution of Complexity

Shannon Entropy in the Research on Stationary Regimes and the Evolution of Complexity

V. M. Eskov$^1$, V. V. Eskov$^1$, Y. V. Vochmina$^1$, D. V. Gorbunov$^1$, L. K. Ilyashenko$^2$

Moscow University Physics Bulletin 2017. 72. N 3. P. 309

The questions of the identification of complex biological systems (complexity) as special self-organizing systems or systems of the third type first defined by W. Weaver in 1948 continue to be of interest. No reports on the evaluation of entropy for systems of the third type were found among the publications currently available to the authors. The present study addresses the parameters of muscle biopotentials recorded using surface interference electromyography and presents the results of calculation of the Shannon entropy, autocorrelation functions, and statistical distribution functions for electromyograms of subjects in different physiological states (rest and tension of muscles). The results do not allow for statistically reliable discrimination between the functional states of muscles. However, the data obtained by calculating electromyogram quasiatttractor parameters and matrices of paired comparisons of electromyogram samples (calculation of the number k of “coinciding” pairs among the electromyogram samples) provide an integral characteristic that allows the identification of substantial differences between the state of rest and the different states of functional activity. Modifications and implementation of new methods in combination with the novel methods of the theory of chaos and self-organization are obviously essential. The stochastic approach paradigm is not applicable to systems of the third type due to continuous and chaotic changes of the parameters of the state vector $x(t)$ of an organism or the contrasting constancy of these parameters (in the case of entropy).

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Astronomy, astrophysics, and cosmology

Improvement of the Orbit of the Spektr-R Spacecraft in the RadioAstron Mission and Required Conditions for Improvement Using a Kalman Filter

Improvement of the Orbit of the Spektr-R Spacecraft in the RadioAstron Mission and Required Conditions for Improvement Using a Kalman Filter

A.S. Zhamkov, V.E. Zharov

Moscow University Physics Bulletin 2017. 72. N 3. P. 318

This paper is concerned with improvement of the state vector of the Spektr-R spacecraft of the RadioAstron mission. The state vector includes three coordinates of the position of the spacecraft and three components of its velocity in the Geocentric Celestial Reference System. Improvement of the orbit of the spacecraft is understood as improvement of the state vector. The results are compared with the original orbits determined at the Keldysh Institute of Applied Mathematics (IAM). The paper considers both using the Kalman filter based on a single set of radio-range and Doppler data from ground-based stations and the analysis of conditions that will lead to improvement of the orbit. It has been shown that using three ground-based stations that perform simultaneous measurements the problem is solved completely, even when a poor initial approximation is used. Based on the results, a list of requirements is obtained that will provide more accurate information on the orbit of the Spektr-R spacecraft.

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Physics of Earth, atmosphere, and hydrosphere

Estimation of Water-Surface Deformation by Vortices in a Viscous Horizontally Decelerating Air Flow

Estimation of Water-Surface Deformation by Vortices in a Viscous Horizontally Decelerating Air Flow

O.N. Mel'nikova, K.V. Pokazeev

Moscow University Physics Bulletin 2017. 72. N 3. P. 326

The maximum height of a disturbance on the water surface, which occurs when a spatial (nonpoint) vortex departs from a viscous layer of a horizontal air flow that decelerates in the direction of motion, is estimated. The dependence of the initial disturbance parameters on the air flow speed over the water surface is derived. It is shown that the height of the disturbance increases and its width decreases with an increase in the air flow speed. The suggested model is verified experimentally

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