Faculty of Physics
M.V.Lomonosov Moscow State University
Astronomy, astrophysics, and cosmology

## Dynamics of the Earth’s radiation belts

### L.V. Tverskaya

Moscow University Physics Bulletin 2010. 65. N 4. P. 246

In this article, we provide a short review of the current state of the field of the radiation belts of the Earth. The main attention is given to the variations of energetic particle fluxes during geomagnetic storms. Electron and proton acceleration mechanisms in the terrestrial magnetosphere are discussed. The possibility of predicting various space weather parameters using the data on relativistic electrons of the outer radiation belt is discussed.

Show Abstract

## The present and future of space materials research

### L.S. Novikov

Moscow University Physics Bulletin 2010. 65. N 4. P. 259

Information on the origination and development of space material research is presented; its basic tasks are the study of physical and chemical mechanisms of the effects of the space environment on materials and the development of methods for increasing the durability of materials and elements of equipment of spacecraft to its influence. The main directions of research are considered, the most important tasks of modern and future studies are formulated, and the prospects of the application of nanotechnologies and nanomaterials in space technology are discussed.

Show Abstract

## Extremely-high-energy cosmic rays: Prospects for research with space-based detectors

### M.I. Panasyuk, B.A. Khrenov

Moscow University Physics Bulletin 2010. 65. N 4. P. 268

The experimental study of high-energy cosmic rays at SINP is based on the legacy left by S.N. Vernov. An abrupt change (cutoff) of the cosmic-ray energy spectrum in the range of ultrahigh energies, ∼5 × 10$^{19}$ eV, was predicted in the works of Greisen-Zatsepin-Kuzmin (GZK). In these and in recent works, it was hypothesized that the shape of the spectrum beyond the GZK limit is related to the evolution of the Universe at the earliest stage of its development, which arouses special interest in studying such extremely high energies. At the same time, experimental study of cosmic-ray particles with such high energies encounters difficulties in connection with their extremely low intensity. To develop a method of particle detection on a maximum area of the order of the Earth’s disk area, in recent years it has been suggested to move from ground-based to space-based detectors. The program of space experiments to study extremely-high-energy cosmic-ray particles is discussed.

Show Abstract

## The magnetospheres of Mercury, Earth, and the giant planets Jupiter and Saturn

### I.I. Alexeev

Moscow University Physics Bulletin 2010. 65. N 4. P. 300

Brief information is given on the magnetospheres of the planets in the solar system that have intrinsic magnetic fields: Mercury, Earth, Jupiter, and Saturn. A universal model is constructed for the magnetosphere of a planet. Modifications of this model that are applied to individual planets are considered. The proposed models describe the basic physical processes that are responsible for the structure and dynamics of the magnetosphere. The numerical results of the simulations are compared with the direct measurements of magnetic fields and charged particle fluxes in the vicinity of the planets obtained in spacecraft (SC) missions.

Show Abstract
Physics of nuclei and elementary particles

## Results of cosmic-ray experiments with emulsion chambers

### I.V. Rakobol’skaya$^1$, T.M. Roganova$^2$

Moscow University Physics Bulletin 2010. 65. N 4. P. 283

The results of experiments with X-ray emulsion chambers performed at SINP over the last 40 years are considered. Wide-ranging experiments to study cosmic rays by this technique were begun at SINP in 1968 with the active support of S.N. Vernov, whose 100th birthday we celebrate in 2010. As a result, the most extensive measurements of cosmic-ray muon spectra were made, the ultrahigh-energy hadron interaction characteristics in the Pamir experiment were investigated, and data on the mass composition of primary cosmic rays in stratospheric experiments were obtained. We took part in these experiments and in the experimental data analysis. The experience of working with emulsion material gained over many years is currently being used in the OPERA experiment to study neutrino oscillations.

Show Abstract
Astronomy, astrophysics, and cosmology

## Cosmic rays in the Earth’s atmosphere

### Y.I. Stozhkov, G.A. Bazilevskaya

Moscow University Physics Bulletin 2010. 65. N 4. P. 239

This paper presents a brief historical overview of studies of cosmic rays in the Earth’s atmosphere, which were initiated and led by S.N. Vernov for over 50 years. The main results of these studies that were obtained in recent decades are given. They include the study of the processes of generation and propagation of solar cosmic rays, the modulation of galactic cosmic rays in the heliomagnetosphere, and the role of cosmic rays in atmospheric processes.

Show Abstract

## The physics of near-earth space plasma and energetic particles in the magnetosphere

### A.P. Kropotkin

Moscow University Physics Bulletin 2010. 65. N 4. P. 252

The magnetosphere-ionosphere plasma system, like the Earth’s other envelopes, is a complex nonlinear open dissipative system with self-organization. Moreover, it is embedded in the extremely nonstationary environment formed by the solar wind. Explorations that were initiated by the pioneer studies of S.N. Vernov and his colleagues resulted in deep insight into the processes occurring in this system.

Show Abstract

## Spectrum and composition of cosmic rays at energies of $10^{15}$-$10^{18}$ eV

### N.N. Kalmykov, L.A. Kuzmichev, G.V. Kulikov, V.V. Prosin, V.P. Sulakov, Yu.A. Fomin

Moscow University Physics Bulletin 2010. 65. N 4. P. 275

EThe energy spectrum and mass composition of primary cosmic rays at energies of $10^{15}$-$10^{18}$ eV are considered on the basis of experimental data from the EAS MSU array, which detects showers by charged particles, and the Tunka-25 array, which uses shower-produced Cherenkov radiation to detect EASs. A change in composition due to an increase in the fraction of heavy nuclei is shown to occur starting from the energy of the knee in the primary energy spectrum and up to $10^{17}$ eV. At energies above $10^{17}$ eV, an additional component that is unrelated to the bulk of the Galactic cosmic rays generated by shock waves in supernova explosions may appear in the energy spectrum. In this case, the fraction of heavy nuclei begins to decrease and the composition is again enriched by light nuclei. A brief description of the new Tunka-133 array with an area of about 1 km$^2$ is given.

Show Abstract

## Main results of the study of ultrahigh-energy cosmic rays in the Yakutsk Extensive Air Shower Array

### A.A. Ivanov, S.P. Knurenko, M.I. Pravdin, I.E. Sleptsov

Moscow University Physics Bulletin 2010. 65. N 4. P. 292

This paper describes the current state of the Yakutsk Extensive Air Shower Array (EASA) and the prospects for its modernization. The main results of the study of the energy spectrum, mass composition, and anisotropy of the ultra-high energy cosmic rays (UHECRs) that were obtained recently by the array are given.

Show Abstract

## Dynamic evolution of triple hierarchical stellar systems

### N.A. Solovaya

Moscow University Physics Bulletin 2010. 65. N 4. P. 322

Dynamic evolution of triple hierarchical stellar systems using higher-order perturbations in the framework of a restricted three-body problem was performed. Hierarchical triple systems consist of a relatively close pair and a satellite on a distant orbit. These systems are thought to be stable on cosmological timescales, in contrast to systems where all the distances are comparable. We obtain a solution for intermediate motion, where the mean motions of both components have secular evolutionary terms. Perturbations from the distant component slow down the rotation of the close pair, while its own mean motion secularly increases due to interaction with the binary component. Perturbations are small but may change the configuration of the system of cosmological timescales. The probability that such systems become unstable is high.

Show Abstract
Chemical physics, physical kinetics, and plasma physics

## Experimental study of patterns of energy input into hybrid low pressure discharge for varying RF generator power and argon pressure

### A.F. Alexandrov, K.V. Vavilin, E.A. Kral’kina, V.B. Pavlov, A.A. Rukhadze, V.P. Savinov, Chen Zhao, V.G. Yakunin

Moscow University Physics Bulletin 2010. 65. N 4. P. 311

Patterns of energy release in the plasma of a new modification of RF discharge, viz., hybrid RF discharge, which are maintained by vortex and potential RF electric fields, are experimentally studied. RF power input unit in the form of inductor and capacitor plates connected in parallel are used for initiating this discharge. This paper presents data obtained during the investigation of the influence of power supplied to the plasma and argon pressure on the equivalent resistance of the hybrid discharge, which is the measure of plasma capability of absorbing RF power. The role of the capacitive channel in the balance of RF power supplied to the discharge is considered.

Show Abstract
Biophysics and medical physics

## The character of cooperative low-frequency oscillations in a model of a biopolymer

### A.Yu. Chikishev$^1$, O.A. Chichigina$^2$, S.A. Shubina$^2$

Moscow University Physics Bulletin 2010. 65. N 4. P. 317

The oscillations in a model of a biopolymer are calculated under various excitation conditions. Relatively slow cooperative motions, which can be used to simulate conformational transitions in a biological macromolecule from one stable state to another, are analyzed.

Show Abstract
Condensed matter physics

## Effects of two relaxation processes on the dielectric spectra and conductivity of ultrathin ferroelectric polymer films

### K.A. Verkhovskaya$^1$, A.A. Plakseev$^1$, I.D. Gavrilova$^2$, A.M. Lotonov$^2$, S.G. Yudin$^1$

Moscow University Physics Bulletin 2010. 65. N 4. P. 307

Based on the study of dielectric dispersion for 2-nm-thick Langmuir films made of an poly(vinylidenefluoride-trifluoroethylene) P(VDF-TrFE) copolymer, we demonstrated the existence of two simultaneously developing relaxation processes. It was shown that Langmuir-Blodgett films are conducting.

Show Abstract
Condensed matter physics

## A study of the influence of methanol and iodine molecule adsorption on the conductivity of Langmuir films of TDOB AM BCC liquid crystals

### N.L. Levshin$^1$, M.N. Martyshov$^1$, P.A. Forsh$^1$, S.V. Khlybov$^1$, S.G. Yudin$^2$

Moscow University Physics Bulletin 2010. 65. N 4. P. 326

This paper studies the influence of adsorption of methanol and iodine molecules on the conductivity of para-tetradecyloxybenzyliden-amino-2-methylbutyl-cyanocinnamate that was obtained using the Langmuir-Blodgett method. The growth of conductivity of the studied films at methanol absorption and the reduction of conductivity upon iodine absorption was discovered. An explanation of the observed conductivity variation at adsorption is proposed.

Show Abstract

## On the possibility of the nucleation of magnetic vortices and antivortices in magnetic dielectrics using electric fields

### A.P. Pyatakov, G.A. Meshkov, A.S. Logginov

Moscow University Physics Bulletin 2010. 65. N 4. P. 329

The micromagnetic distribution in a dielectric nanoparticle is theoretically considered. It is shown that the presence of an inhomogeneous magnetoelectric interaction in magnetic dielectrics creates the possibility of nucleation of magnetic vortices and antivortices in them using an electric field. The estimation of the critical voltage necessary for vortex creation in particles of high-temperature multiferroic bismuth ferrite yields a value of ∼100 V.

Show Abstract