R e g u l a r p a p e r s

Moscow University Physics Bulletin 1982. **37**. N 5. P. 1

A differential equation is obtained relating the energy and coordinate of a charged particle in an interaction with the field of a plane electromagnetic wave of nonunity phase velocity. A method of solving the derived equation allowing the electron energy and coordinate to be analytically elucidated in terms of an introduced parameter using the Wieerstrass function is presented. On the basis of the solution of the nonlinear differential equation constructed and the constraints imposed on the parameters of the given system, an expression relating the particle energy and coordinate is obtained. The results of tabulating the expression obtained is compared with the results of numerical integration of the relativistic equations of motion.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 7

The reasons for the deformation of the absorption spectra of dye molecules with change in their immediate surroundings by the introduction of other molecules - in particular, surfactant molecules - into their solvate shells is considered. It is shown that these changes may be explained on the basis of the idea of the development of the hypochromic effect in dispersional interactions and of the shift in the system of electronic - vibrational levels under the influence of the field of closely spaced molecules.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 12

It is shown that using the energy - momentum tensor of material in the form T$^{ij}$= (ε+p)τ$^{i}$τ$^{j}$-g$^{ij}$p with wave emission in a relativistic plasma leads to incorrect dispersion of the plasma waves. A closed system of equations for relativistic plasma is constructed in the hydrodynamic approximation, taking the retardation of the radiation into account, and on this basis the dispersion and radiational - damping decrements of the wave are obtained, with results that do not contradict kinetic theory.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 17

On the basis of Tikhonov regularization theory, the problem of the heating of cylindrical samples under tempering in an inductor with a transverse magnetic field is considered. The a priori requirements on the resulting characteristics of the heating process are determined by the time dependence of the current strength needed for their determination.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 23

The structure of the heterogeneous superconducting state is investigated on the basis of the Yang - Mills gage-field theory. Taking magneticf luctuations into account leads to an eddy structure different from the structure in usual superconductors of the second type. The flux quantum of this eddy is calculated. In the system, phase transitions from one heterogeneous superconducting state to another are possible; these are found to be phase transitions of the first type, close to the second type.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 29

The local distribution of atoms in solid solutions of iron in α and β modifications of manganese is studied by the methods of X - ray structural analysis of polycrystals and nuclear γ resonance. Concentrational dependences of the distribution of iron and manganese atoms for α and β solid solutions are obtained, and the ordered distribution of iron atoms in the structures of α and β Mn is experimentally observed. It is established that, at the boundaries of single - phase α and β solid solutions, the distribution of iron atoms in α and β Mn structures corresponds to the mean statistical distribution, and on this basis it is concluded that the configurational energy plays the decisive role in the stabilization of α and β phases in Mn - Fe alloys.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 34

A theoretical and computer Investigation is made of the Influence of spatial and dynamic heterogeneity in the distribution of nonequilibrium conductivity in a semiconducting plate on the response in a SHF-displacement circuit. It is shown that spatial heterogeneity of the distribution leads to deterioration in conversion efficiency of the signal from the optical to the SHF range, and dynamic heterogeneity to increase in inertia of the.SHF circuit with a semiconducting sample. A relation is obtained allowing the thickness of the semiconductor sample at which there is no-heterogeneity of the distribution of either type to be determined.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 40

A solid-state laser with a filter operating under conditions of overlap of the saturation stages of the active medium and the nonlinear absorber, with large amplification factors of the active medium, is considered. It is shown that the superliminesence arising under these conditions, which reduces the need for precise maintenance of the optimum level of pumping, may facilitate an increase in the probability of obtaining stable ultrashort pulses with high contrast.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 45

The correlation of light intensities in the quasielastic scattering of two - beam pumping is investigated. It is shown that the fields scattered in different directions will be statistically related under two different conditions of spatial synchronism. The relation between this effect and the effect of correlation of the Stokes and anti-Stokes components of Raman scattering is considered.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 48

The question of accurately taking account of the real extended relief into account in the two - dimensional flow problem (in avertical plane) is considered. The algorithm constructed may also be used in other theoretical models. It is shown, in several examples of calculations for real mountains, that in the flow problem sufficient accuracy is necessary both in taking account of the lower boundary condition and in calculating the trajectories of motion. Calculations show that the perturbations are intense immediately above the mountains, and are almost degenerate in the leeward direction.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 56

The urgency of increasing the speed of operation of nonself - quenching counters is shown; the load characteristics of the counters are considered, together with the basic reasons for their low operating speed and means of eliminating them. An equivalent scheme is proposed for calculating the amplitude and other parameters of the electric pulse, the dependence of the deionization rate on the switching circuit is shown, and a switching circuit allowing the speed of operation of the counters to be increased is described.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 63

On the basis of an approach associated with the concept of Bogolyubov quasimeans, a model is proposed allowing the coexistence of normal and superconducting components in superconductors at subcritical temperatures to be described. The corresponding phase concentrations are determined in a self-consistent manner as a function of the temperature and the parameters of the interaction. In the approximation of strongpairing and constant four-fermion interaction, expressions are obtained for the phase concentrations and order parameter. The difference from the standard BKSh theory is considered.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 68

Root hodographs of systems described by the equation $(a_0p^5+a_1p^4+a_2p^3+a_3p^2+a_4p+a_5)+K=0$ in the complex - frequency plane p are considered. Relations are found between the coefficients $a_i$ determining the types of root trajectory. From the analysis of types of root hodographs, the possible dynamic properties of such systems are established, allowing their investigation and calculation to be more expediently conducted.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 75

The relativistic equations of a vector field in an external magnetic field are investigated. The known arbitrariness in choosing the Lagrangian of a vector field in an external electromagnetic field allows the phenomenological parameter k, characterizing the magnetic moment of the particle, to be introduced. The case k = 1 corresponds to the 1967 Winberg model. In the present work, accurate solutions of the vector equations are obtained both in the case k = 1 and for arbitrary k. The spin states of the particles are considered. An energy spectrum of a vector particle in a magnetic field agreeing with earlier known results is found.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 81

Two limiting cases of the acoustooptical interaction of bounded light and ultrasound beams are considered: diffraction of the light beam at a monochromatic acoustic wave and diffraction of a plane light wave at an acoustic wave train. It is shown that, even with the same dimensions of the interaction region, there are significant differences in the structure of the diffracted - light field and in the character of the dependence of the diffraction efficiency of the parameters of the acoustic cell.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 88

The muon decay μ→eνν ̅and the inverse process ν$_{μ}$e$^{-}$→ν$_{e}$ μ ν$^{-}$ is investigated in the case of the interaction of charged and nondiagonal neutral lepton currents of general form. It is shown how the structure of the interaction may be established using experimental data on these processes. On the basis of the known values of the μ-deсay parameters, bounds on the coupling constants of the currents are obtained.

Show AbstractB r i e f r e p o r t s

Moscow University Physics Bulletin 1982. **37**. N 5. P. 95

Certain characteristics of rectennas used as receivers and converters of VHP energy into DC energy in energy - transfer systems using VHF beams are theoretically and experimentally investigated.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 98

The application of a variant of the sensitive - point method in studying the distribution of a constant magnetic field in the gap of a highresolution NMR spectrometer is considered. A method of producing two sensitive points is developed and theoretically verified: a motionless point which is used for internal proton stabilization and point scanning over the investigated volume. The following - receiver method is used to derive the NMR signal from the scanning sensitive point. The experimental apparatus is described.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 102

The local - coordinate method is used to investigate the synchrotron radiation of ultrarelativistic particles moving in a magnetic field in curved space-time. General covariant formulas are obtained for the radiation spectrum in the classical and quantum cases. It is shown that the radiation intensity and the relative values of the quantum corrections increase when the particle moves close to the event horizons in the Schwartzschild metric. The limiting transition to conditions of geodesic synchrotron radiation is considered.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 106

The results of theoretical and experimental investigation of synchronous conditions of two generators connected by unidirectional couplings are presented. The possibility of controlling the frequency of the system by means of an asynchronous external force is shown.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 110

The results of investigating the diffusion coefficient in the nitrobenzene - heptane system along the coexistence curve are presented. The parameters of the temperature and concentration dependences of diffusion are measured. It is shown that the character of the singularity in the diffusion coefficient as a function of the concenration is due to the properties of the coexistence curve.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 114

Riparian autonomous currents are investigated in channel flow, and the force field is determined from the isotach distribution in the flow cross section. The criteria determining the flow parameters at which riparian autonomous currents arise are discussed.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 118

The phase relations In nonlinear acoustic interactions are experimentally investigated.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 119

It is established that in magnetite, in the vicinity of the spln-reorientational transition, the spin system is unstable not only with respect to strong, but also to weak, external perturbations. Analysis of the results on magnetization, magnetocaloric effect, magnetic permittivity, and specific heat leads to the conclusion that the spin-reorientational transition Ф <111> ↔ Ф <100> in magnetite at low temperatures occurs without spinodal decay.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 122

The magnetic bremsstrahlung of a neutrino pair is considered, taking account of the initial or final electron polarization within the framework of the Weinberg-Salam weak-interaction model. In the case of ultrarelativistic particle energies, the transition to crossed fields is made, and expressions are obtained for the probability of the process in the two limiting cases: χ=Hеp$_{0}/m$^{3}$≪l and χ≫1.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 126

The specific heat of three compounds Ni$_{x}$Co$_{1-x}$Cl$_{2}$ with x = 0.10, 0.18, and 0.90 in the temperature range 2-27 К is measured. Together with previous measurements on NiCl$_{2}$ and CoCl$_{2}$, the results are compared with the theory of spin waves of laminar antiferromagnets.

Show AbstractMoscow University Physics Bulletin 1982. **37**. N 5. P. 131

Specific form is given to the action and, correspondingly, the effective metric for a trial particle constructed in an earlier work. It is shown that this metric identically satisfies the Einstein equations at each step of the iteration.

Show Abstract