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

Theoretical and mathematical physics

Moscow University Physics Bulletin 1988. **1988**. N 5. P. 1

It is found that there is а sp ecific direct nonde layed interaction between fundamental particles in the region of а classical particle- type cluster, which is due to quantum fluctuations in the cluster's center of mass.

Show AbstractMoscow University Physics Bulletin 1988. **1988**. N 5. P. 4

А 6-dirnensional geornetrical theory is proposed that cornbines the general theory of relativity with the Weinberg-Salam weak interaction model; а metrical method is used for introducing the W± bosons subject to abandoning the metric cylindricity condition with respect to the additional coordinates. А mass mechanism of Higgs type leads to а correct relation between the W± and Z bosons. Тhere is cornplete correspondence with the Weinberg-Salam model. А theoretical value for the Weinberg angle is derived (θ_w = 30°).

Show AbstractMoscow University Physics Bulletin 1988. **1988**. N 5. P. 9

Тhе fall in the ground state in а center ($Еo→-∞,ψo^2→ δ(х)$) in а one-dimensional Coulomb attraction field is not related to elevated symmetry in that field but occurs also for attraction potentials $\lambda|x|^{-\nu}, 0<\nu< 2$, although it can bе readily removed bу altering the boundary conditions, in contrast to the fall in а central field (ν≥2,λ<O). Тhе parity degeneracy is lifted automatically with the elimination of the drop in the ground- state level.

Show AbstractMoscow University Physics Bulletin 1988. **1988**. N 5. P. 13

A study has been made on how continuous measurement affects the behavior of a two-level quantum system whose free evolution is characterized by oscillations between levels. As the measurement accuracy increases, the oscillation frequency decreases, and at a certain accuracy, the oscillations are replaced by aperiodic transition to the equilibrium state. The transition time-constant increases with the accuracy. If the system is tracked with absolute accuracy, it is frozen in the initial level.

Show AbstractMoscow University Physics Bulletin 1988. **1988**. N 5. P. 19

А new model choice method is proposed together with а method of best testing; а numerical analysis is performed in relation to determining an unknown model parameter.

Show AbstractMoscow University Physics Bulletin 1988. **1988**. N 5. P. 25

The current relations are derived for the multiple covariant derivatives of bilocal functions in а Riernann rnanifold; the geodesic interval and the parallel- translation operator are considered, and the derivatives of the van Vleck deterrninant up to the fifth order inclusive have been calculated.

Show AbstractMoscow University Physics Bulletin 1988. **1988**. N 5. P. 31

Hamiltonian special-function theory is applied in an algorithm for constructing higher WCB approximations. Successive diagonalizations are applied to the Hamiltonian that generates the wave equation, where each stage involves an exact transformation for the initial equations.

Show AbstractMoscow University Physics Bulletin 1988. **1988**. N 5. P. 39

Тhе properties of cerium near the critical point are considered in terms of one- component system thermodynamics; а thermal equation of state containing Р, V, and Т has been derived. Тhе equilibri um line terminates at the critical point. Тhе critical parameters have been calculated:$\alpha = 0, \gamma=1, \beta = 1/2, \delta = 3$.

Show AbstractAtomic and nuclear physics

Moscow University Physics Bulletin 1988. **1988**. N 5. P. 45

A study has been made on the scope for observing parity nonconservation in elastic polarized-electron scattering by nuclei at E < 1 GeV. It is shown that electron accelerators under design should allow one to observe the asymmetry in such scattering due to weak lepton-hadron interaction.

Show AbstractMoscow University Physics Bulletin 1988. **1988**. N 5. P. 49

Charge spectra have been recorded with satisfactory resolution at energies over. l TeV bу an apparatus containing two sectional Cherenkov charge detectors and а sectional ionization calorimeter providing about 5.5 proton interaction ranges; it has been used with the Cosmos satellites in 1984- 1986. Evidence has been found for а minor effect from the reverse secondary- particle current from the calorimeter in the charge measurements (at energies of several TeV).

Show AbstractRadiophysics

Moscow University Physics Bulletin 1988. **1988**. N 5. P. 55

Anisotropic diffraction is considered for two acoustic waves differing in frequency propagating in the sarne direction in а crystal. The Bragg- peak intensities have been calculated as functions of arnplitude and frequency. The two- frequency state can thus bе used to exarnine anisotropic diffraction in acoustooptic devices.

Show AbstractOptics and spectroscopy

Moscow University Physics Bulletin 1988. **1988**. N 5. P. 61

Monte Carlo methods have been applied to nonlinear optical processes in organic complexes of phycobilosome type; the nonlinearities are governed Ьу single- singlet annihilation and absorption saturation. The annihilation parameters are time- dependent, and mean values have been calculated.

Show AbstractMoscow University Physics Bulletin 1988. **1988**. N 5. P. 66

The population difference has been calculated for the levels in а twolevel atom in а strong field with allowance for the inelastic interaction with the dephasing noise, which modulates the transition fre quency; а saturating field means that there is the frequency - difference range in which the stationary population difference is inverted because of the asyrnmetry in the absorption and emission of the quanta responsible for the dephasing.

Show AbstractAcoustics and molecular physics

Moscow University Physics Bulletin 1988. **1988**. N 5. P. 70

Thermooptic sound excitation has been examined for а boundary between transparent and absorbing heat- conducting media for any ratio of the acoustic impedances; тedia may bе classified as regards how the conductivity affects the generation. Spectral transfer functions are used. А detailed study has been таdе on strongly and weakly conducting тedia. The results еnаblе one to optimize opticoacoustic devices.

Show AbstractAstronomy

Moscow University Physics Bulletin 1988. **1988**. N 5. P. 76

Results from an earlier qualitative analysis on asteroid motion near 2:1 commensurability with Jupiter are compared with those from numerical integration for the equations governing the planar form in the circular restricted three- body problem.

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

Theoretical and mathematical physics

Moscow University Physics Bulletin 1988. **1988**. N 5. P. 81

Calculations have been performed on the contribution from the 1.6 MeV pseudoscalar boson to the lepton g factor in а constant magnetic field. The magnitude is dependent on the lepton energy and field strength. Numerical estimates have been made and are compared with the contributions from weak interactions.

Show AbstractRadiophysics

Moscow University Physics Bulletin 1988. **1988**. N 5. P. 83

Measruements have been made on the nonlinearity in the dielectric constant $\alpa$ for nematic liquid crystals in the range 1- 33 MHz: $\alpha=1,5\cdot 10^{-3} cm^3/erg$. The frequency dependence of $\alpha$ and tan $tg \delta$ has been determined, as well as the temperature dependence of $\alpha$ and $\epsilon$.

Show AbstractMoscow University Physics Bulletin 1988. **1988**. N 5. P. 86

А numerical study has been made on how absorption affects the size and position of the region in parameter space for an anharmonic oscillator subject to harmonic external force within which one gets period multiplication and dynamic chaos.

Show AbstractOptics and spectroscopy

Moscow University Physics Bulletin 1988. **1988**. N 5. P. 89

It is found that the main restrictive factor is induced Raman scattering gain saturation in pumping а synchronous dye laser with the second harmonic of а picosecond laser based on $(KGd(WO_4)_2:Nd^{3+})$.

Show AbstractAcoustics and molecular physics

Moscow University Physics Bulletin 1988. **1988**. N 5. P. 92

The plane of polar ization for the second har monic is rotated in nonlinear shear SH wave reflection from solid interfaces.

Show AbstractSolid state physics

Moscow University Physics Bulletin 1988. **1988**. N 5. P. 95

Electron microscopy has been applied to surface structure and emissivity for polycrystalline tungsten carbide and molybdenum and also tungsten single crystals irradiated bу ϒ- rays, including how these characteristics vary on annealing.

Show AbstractMoscow University Physics Bulletin 1988. **1988**. N 5. P. 97

Low- temperature magnetometry and X- ray diffraction have been applied to $(Tb_{0,75} Ho_{0,25})_{1-x}Dy_xCo_2$ alloys; а spin- orientat ion phase diagram has been constructed.

Show AbstractMoscow University Physics Bulletin 1988. **1988**. N 5. P. 100

Ar^+ implantation in Si is accompanied Ьу the formation of adsorptiontype defect complexes at the surface at doses above 10^11 ion·cm^{-2}, which accelerates the surface conductivity relaxation and markedly increases the l/f type current noise.

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