Issue 5, 1997
D.D. Sokolov
D.D. Sokolov
Discontinuous distributions of transport coefficients in mean-field electrodynamics
An extension of the mean-field electrodynamics equations is proposed that enables discontinuous distributions of chirality to Ье described in its framework. А relation between the phenomena that take place at the jump surface of the magnetic diffusion coefficient and the time evolution of the magnetic moment is considered.
Show AbstractComputer simulation of spontaneous decay of а three-particle cluster
Computer simulation of spontaneous decay of а three-particle cluster
О.А. Chichigina
The spontaneous decay of а cluster of three identical atoms or molecules, whose interaction is described Ьу the Lennard-Jones potential, has been simulated. The mean cluster lifetime and decay curves have been produced for energy values higher than the maximum energy of а staЫe cluster but close to this value. The numerical data virtually coincide with analytical calculations obtained earlier on the basis of the dynamic theory.
Show AbstractClassification of solutions of а special kind of nonlinear Schrodinger-type equations
Classification of solutions of а special kind of nonlinear Schrodinger-type equations
A.G. Kornienko, A.R. Frenkin, and G.A. Chizhov
Classification has been made of solutions of unidimensional Schrodinger-type nonlinear equations in the form of solitary waves, obtained bу the quadrature method. Effective potentials for corresponding differential equations have been considered and the structure of the phase plane has been studied. Examples of nonstationary and oscillating solutions of these equations have been given.
Show AbstractSоmе nеw relations for the electromagnetic field tensor in pseudo-Riemannian space-time
Sоmе nеw relations for the electromagnetic field tensor in pseudo-Riemannian space-time
V.I. Grigor'ev and I.Р. Denisova
Explicit expressions for powers ofthe electromagnetic field tensor in terms ofthe three lowest powers of this tensor, the metric tensor of the pseudo-Riemannian space-time and two independent invariants of the electromagnetic field have been obtained.
Show AbstractReconstruction of electron concentration profile for plasma layers of different size from radiosonde observation data
Reconstruction of electron concentration profile for plasma layers of different size from radiosonde observation data
V.E. Kunitsyn and I.А. Nesterov
The impact ofthe layer size on the feasiЬility oflayer reconstruction is discussed. For high potentials with valleys, the reflection coefficient is shown to change abruptly within the narrow frequency intervals; outside these intervals the geometrical optics approximation is applicaЪle to а high precision. With increasing potential, the intervals width decreases rapidly (at an exponential rate), and the intervals bесоmе practically indiscernible, therefore, in actual practice, full information about the potential cannot bе obtained, which leads to an ambiguous solution of the inverse proЪlem.
Show AbstractRegularized scaling factor method for calculatiпg molecнle force fields
Regularized scaling factor method for calculatiпg molecнle force fields
I.V. Kochikov, G.M. Kuramshina, A.V. Stepanova, and A.G. Yagola
А regularizing algorithm has been implemented for calculating the force fields of polyatomic molecules. The algorithm is based on Pulay's method of scaling factors.
Show AbstractMagnetic hyperfine fields AT^181Та nuclei in the laves phases RFe_2 (R = ТЬ, Но, Уb)
Magnetic hyperfine fields AT^181Та nuclei in the laves phases RFe_2 (R = ТЬ, Но, Уb)
А.А. Sorokin, В.А. Komissarova, G.K. Ryasnyi, S.I. Reiman, L.G. Shpin'kova, A.V. Tsvyashchenko, E.N. Shirani, L.N. Fomicheva, and A.S. Deпisova
The method of ϒϒ-perturbed arigular correlations was used to measure magnetic hyperfine fields Вhf at the 181^Та nuclei in the Laves phases YbFe2, HoFe2, and TbFe2. At 300К the following Вhf(Та) values were oЬtained: 18.5 Т, 16.2 Т, and 12.1 Т, respectively. The experimental results are compared with the data obtained bу us earlier for other phases RFe2.
Show AbstractDispersion properties of planar shielded waveguides with Kerr's dielectric
Dispersion properties of planar shielded waveguides with Kerr's dielectric
A.F. Aleksandrov and V.A. Kubarev
Propagation of electromagnetic waves in waveguides completely or partially filled witli а Kerr-type medium with positive nonlinearity is considered. Dispersion relations have been obtained and dispersion characteristics have been studied. It is shown that the dependence of wave retardation on its intensity is Kerr in nature with а certain effective nonlinearity coefficient.
Show Abstractlncoherent signal accumulation in gravity-wave experiment
lncoherent signal accumulation in gravity-wave experiment
М.Р. Vinogradov, A.V. Gusev, and V.K. Milyukov
An incoherent accumulator of gravity radiation bursts has been synthesized on the basis of the generalized maximum likelihood criterion for an integrated data processing system. А technique has been developed for estimating the probability of errors of the first kind for а non-Gaussian approximation of the source statistics.
Show AbstractEffect of anti-Stokes component on tl1e gain of stimulated Rama11 scattering in plasma
Effect of anti-Stokes component on tl1e gain of stimulated Rama11 scattering in plasma
0.М. Bilak and S.Yu. Nikitin
The authors have calculated the correction to the gain of stimulated Raman scattering (SRS) in а homogeneous plasma due to the effect of the anti-Stokes scattering component. It has been shown that for conditions close to those of laser fusion synthesis this correction does not exceed а few percent and is independent of the pumping intensity.
Show AbstractNonreciprocal effects in ring Raman lasers
Nonreciprocal effects in ring Raman lasers
N.V. Kravtsov апd N.I. Naumkin
The initiation of amplitude and frequency nonreciprocity in а pulsed ring Raman laser with compressed hydrogen has been studied experimentally. The character and magnitude of nonreciprocal effects have been shown to depend on the density of radiation power in the laser resonator. The observed effects are analyzed on the assumption of spatial nonuniformity of the nonlinear medium and the formation of а wave front reversal mirror.
Show AbstractPropagation of wide-band acoustic pulses in unidirectional fibrous
Propagation of wide-band acoustic pulses in unidirectional fibrous
А.А. Karabutov, I.М. Kershtein, I.М. Pelivanov, апd N.V. Podymova
Propagation of acoustic videopulses in unidirectional fibrous graphite-epoxy composites is studied. The immersion technique with thermooptical ultrasound excitation is used. Experiments have shown that the mechanical properties of such media can bе described bу the orthotropic model. ln the frequency range of from 1 to 15 MHz, frequency dispersion of phase velocity has not been observed independently of the direction of ultrasound propagation in the composite.
Show AbstractSpin-torsional interactions in magnetic substances
Spin-torsional interactions in magnetic substances
S.A. Istomin and R.N. Kuz'min
А Lagrangian has been constructed and а system of dynamic equations has been derived that describe an elastic ferromagnet under the action of external magnetic and torsional fields. It has been shown that an external torsional field affects the mechanical state of magnetics and their magnetization. Analysis of the equations has revealed some features inherent in the spin-torsional interaction in magnetics. А feasiЬle experiment has been proposed for detecting spin-torsional interactions in magnetic substances. The range of admissiЫe values of the spin-torsional interaction constant has been estimated.
Show AbstractInfluence of ferroelectric phase transition on Langmuir- Blodgett film adsorption properties
Influence of ferroelectric phase transition on Langmuir- Blodgett film adsorption properties
N.L. Levshin, S.G. Yudin, and А.Р. Diankina
Adsorption isotherms of water molecules and hexane on the surface of polar Langmuir-Blodgett films (VDF/TrFE} have been obtained bу the method of piezoresonance quartz balance at several measurement temperatures. The ferroelectric phase transition of the first kind in the film was found to influence the adsorption capacity of the adsorbent.
Show AbstractOscillatory disintegration of small-amplitude magnetohydrodynamic shock waves
Oscillatory disintegration of small-amplitude magnetohydrodynamic shock waves
S.A. Markovskii
А new scenario of time evolution of small-amplitude trans-Alfvenic shock waves is suggested. The scenario is the oscillatory disintegration, i.e., the mutually reversible transformation into an Alfven discontinuity. Simultaneously, shock and self-similar waves are emitted and contact discontinuities occur. Thus, а nonevolutionary shock wave cannot exist as а steady flow.
Show AbstractInfluence of polarization potential on probaЬilities of free-free electron transitions
Influence of polarization potential on probaЬilities of free-free electron transitions
N.Yu. Dobrolyubov, V.D. Kukin, and V.S. Rostovskii
А method for evaluating the matrix element of an electric dipole transition between the states of the continuous spectrum with regard to the existence of an atom of Coulomb and polarization potentials in the exterior region has been considered. Recurrent formulas for evaluating the contribution of the integral over the domain outside the atom to the matrix element with the use of the values of the radial wave functions and their first derivatives on the boundary have been obtained.
Show AbstractRelation for nonlocality parameters of gluon and four-quark condensates of QCD from finiteenergy sum rules
Relation for nonlocality parameters of gluon and four-quark condensates of QCD from finiteenergy sum rules
D.V. Meshcheryakov and V.B. Tverskoi
In the framework of the finite-energy sum rules method а relation has been obtained for the nonlocality parameters of the four-quark and gluon condensates of QCD.
Show AbstractNeutrino pair production bу virtual photon in external magnetic field
Neutrino pair production bу virtual photon in external magnetic field
V.Ch. Zhukovskii, А.Е. Grigoruk, K.G. Levchenko, and Р.А. Eminov
Production of а massive neutrino-antineutrino pair bу а virtual polarized photon in the Weinberg-Salam model with mixing has been studied. The rate of the neutrino pair production bу photons with various polarizations at values of the magnetic field strength lower than critical has been found.
Show AbstractOn magnetic moment of Cr^{3+} ion in ferrites-chromites with spinel structure
On magnetic moment of Cr^{3+} ion in ferrites-chromites with spinel structure
A.N. Goryaga, L.G. Antoshina, and E.N. Kukudzhanova
The behaviour ofthe paramagnetic susceptibllity ofa series offerrites-chromites samples with а high content of Cr$^{3+}$ ions has been studied. The experimental value of the Curie-Weiss constant has been found to bе much smaller than the theoretical one on the basis of the obtained results and making use of the results of NMR study in the compound MgO with an admixture of Cr$^{3+}$ ions. For the first time the authors have made а proposal that the understated values of the experimental magnetic moments of ferrites-chromites with а high content of chromium ions may also bе due, together with other reasons, to а decrease in the magnetic moment of Cr$^{3+}$ $({t^3}_{2g},{e^0}_g)$ ions because of the transfer of the spin density from О$^{2-}$ ions to the vacant eg-orbltals of Cr$^{3+}$ ions.
Show Abstract