This paper considers a two-dimensional network of quadratic mappings with diffusive and parametric interaction between the elements and its approximate model, which consists of a single (selected) element of the network and a fluctuating medium. It is shown that certain effects of the fluctuating medium can result in destochastization, i.e., suppression of chaos in the selected element. The upper threshold is found for diffusion at which this phenomenon is still retained.
Show AbstractVarious approaches to the determination of states with minimum indeterminacy are analyzed. An equation for states with minimum indeterminacy is obtained, which is more general than the earlier used ones. The suggested approach is illustrated by the indeterminacy ratio between the phase and the number of quanta for a harmonic oscillator.
Show AbstractWithin the framework of the six-dimensional geometrical theory of gravi-electroweak interactions, the possible variation of fundamental physical constants in developing homogeneous isotropic cosmological models is considered. In this theory the electric charges and the masses depend on time, and the cosmological shift of light spectral lines is due to two factors: the Doppler effect and the variation of fundamental constants during the time of light propagation. Because these factors strengthen each other, the age of the Universe turns out to be greater than in the standard Friedmann model.
Show AbstractA method of projection operators is suggested for calculating multipulse and multiquantum processes of nuclear magnetic resonance (NMR). The applications of the method are considered in the theory of double resonance and for the calculation of multiquantum coherence in systems with quadrupole moment and in systems with scalar spin-spin coupling.
Show AbstractCalculations of differential cross sections of (e, 2e) reactions on Cu and Ag atoms in the eikonal approximation are described for ( e, 2e) experiments that have recently been carried out in Tiibingen. It is shown that even for highenergy impinging particles the angular profile of the differential scattering cross section is sensitive to the magnitude of the mean intraatomic field. This suggests the idea of using the angular shift of the maximum of the differential scattering cross section in symmetric (e, 2e) experiments for direct determination of the mean intraatomic field.
Show AbstractThe first stage of a continuous-operation accelerator, the slot microtron designed at the Research Institute of Nuclear Physics, Moscow State University, was used to study the nuclear resonance fluorescence, the $(\gamma, \gamma’)$ reaction. The $^{11}В$, $^{19}F$, $^{23}Na$, $^{28}Si$, $^{32}S$, $^{39}K$, $^{63}Cu$, and $^{208}Pb$ nuclei were studied. The results are compared with data obtained on similar accelerators.
Show AbstractThe feasibility of quantum nondisturbing measurement of the photon energy and the energy of zero-point oscillations of the dielectric resonator mode is shown. The technique is based on the effect of quadratic scattering of electrons traveling along the resonator with a velocity close to the phase velocity of the wave in the resonator.
Show AbstractAn effective numerical-analysis method is proposed for determining the characteristics of radiation from an irregular horn given the distribution of surface impedance on the lateral walls and the inhomogeneous filling. Numerical results are presented, which testify that it is possible to control the electromagnetic radiation. The algorithm is based on the incomplete Galerkin method with semi-inversion in the boundary condition.
Show AbstractThe performance of a collinear acoustooptical filter is theoretically analyzed with consideration for diffraction-induced divergence between the light and the acoustic beams. The effect of beam divergence on the transmission band and on the number of optical image elements that can be studied with the aid of the filter is described. The parameters needed for an optimal performance of the filter are determined.
Show AbstractThe behavior of the nonlinear frequency shift and the amplitudes of the second and third harmonics have been studied numerically in the cubic approximation with respect to the wave field for the relativistic Maxwell plasma. The range of applicability of low-temperature asymptotics is indicated for quantities under study. It is found that for waves with a phase velocity close to the velocity of light a good approximation is given by cold hydrodynamics.
Show AbstractAn experimental study of the transformation of a video pulse of longitudinal waves with a planar phase front into shear waves at the liquid-solid interface is reported. Longitudinal wave pulses from standard laser sound sources had mono- and bipolar shapes in the spectral range of 1 to 70 MHz. Shear wave pulses with a planar phase front and linear polarization were detected in the spectral range of 1 to 15 MHz.
Show AbstractA method is proposed for the evaluation of the localization depth and the magnitude of a mass from the values of anomalies and the vertical gravity gradient. A function which depends on the distance to the perturbing mass is introduced, and the mass and its depth of occurrence are evaluated.
Show AbstractIt is shown that the equations of satellite motion in the solar system with consideration for its galactic rotation make it possible, in the reference frame of local geocentric observer, to reveal the effects induced by the galactic rotation.
Show AbstractAn optimal two-pulse flight to the $L_3$ libration point of the Earth-Moon system is studied in the context of planar restricted elliptical three-body problem with the use of asymptotic trajectories. The minimum energy requirements for this transfer and the value of the parameter $v$ (true anomaly of the Moon) characterizing the asymptotic trajectory are determined.
Show AbstractExperimental data have been used to build and analyze magnetic phase diagrams of $Gd_xCe_{1-x}MnSi$. Pressures of about 8-10 kbar have been found to induce antiferromagnetic ordering within the Mn sublattice for all the compounds studied. The results obtained are discussed on the assumption that the exchange interaction inside the ferromagnetically ordered layers prevails over the interlayer exchange interaction.
Show AbstractThe crystal structure, phase composition, and magnetic properties of $SmFe_{11-x}Co_xTi$ compounds (x = 0, 1, 2, 3, 5) were studied. The temperature dependence of magnutization, the Curie temperature $Т_с$ and the saturation magnetization were determined for single crystals prepared from ingots of $SmFe_{11-x}Co_xTi$ alloys. Uniaxial magnetic anisotropy constants were estimated by the torque method. It was found that $SmFe_{11-x}Co_xTi$ compounds have high magnetic energy, saturation magnetization and magnetic anisotropy. It was also found that the Curie temperature grows drastically as cobalt is substituted for iron and reaches the level of $Т_с = 960$ К for $SmFe_6Co_5Ti$, which provides increased thermal stability of these alloys.
Show AbstractA new model of decomposition of polyatomic molecules upon interaction with inert gas ions is proposed. The criterion of molecular bond breakage is the amount by which the bonding energy changes as a result of charge exchange between the ion and the molecule.
Show AbstractWaves of arbitrary amplitude in the Fermi and the ultrarelativistic plasma are considered. In contrast to the linear theory, the properties of waves of finite amplitude in these media possess some substantial distinctions.
Show AbstractThe pressure dependence of the coefficients of reflection of waves of the first and second harmonics from the surface of a pressed contact carries information on the statistical characteristics of the microprotrusion sizes. A model is proposed that represents the contact as an ensemble of springs of variable lengths. A method based on this model is suggested for processing experimental acoustic data. An estimate of the characteristic size is obtained for a surface roughness element, which corresponds to the surface finish class.
Show AbstractA design of an acceleration pickup comprising three mutually perpendicular reception channels is proposed and its main parameters are described. The pickup can be applied in hydroacoustics and seismometry.
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