Features of the interaction of dense electron beams with transversely nonuniform anisotropic plasma
Features of the interaction of dense electron beams with transversely nonuniform anisotropic plasma
M.V. Kuzelev, A.N. Khalilov
A numerical study of the role of nonlinear effects in plasma in the course of development of beam-plasma instability in a waveguide is followed by an analysis of the field and the beam density perturbations, and the soliton-like plasma produced during this process. A quantitative criterion of applicability of a linear (in terms of plasma electrons) approximation to the theory of beam-plasma interactions is derived.
Show AbstractSpatial resolution of images in semiconductor structure investigation using a scanning electron microscope in the local cathodoluminescence mode
Spatial resolution of images in semiconductor structure investigation using a scanning electron microscope in the local cathodoluminescence mode
A.R. Gareeva, R.S. Gvozdover, V.I. Petrov, V.A. El'tekov
Analysis of spatial resolution in a scanning electron microscopy study of semiconductors in the local cathodoluminescence mode has been made on the basis of electron trajectory simulation by the Monte Carlo method. A high spatial resolution is shown to be attainable at accelerating voltages of 10 to 20 kV. The experimental results obtained during the cathodoluminescence study of n-GaP are in agreement with the computed values of spatial resolution.
Show Abstract1/f noise in low-frequency seismic sensors
1/f noise in low-frequency seismic sensors
A.V. Gusev, V.K. Kravchuk, I.V. Rytik
Inherent noises in low-frequency modulation-type seismic sensors have been investigated. Algorithms for the optimum digital filtration of the output signal have been developed. A formula to calculate the noise factor for random flicker noise parameters is presented.
Show AbstractDynamic model of electron-phonon transitions in nonlinear biharmonic-pumping spectroscopy of semiconductors
Dynamic model of electron-phonon transitions in nonlinear biharmonic-pumping spectroscopy of semiconductors
B.A. Grishanin, V.M. Petnikova, V.V. Shuvalov
A dynamic model of the four-photon response is proposed to interpret the dispersion relations obtained by biharmonic pumping in the range of interband absorption in gallium selenide. The intraband electron-phonon relaxation processes are described in the adiabatic approximation, with the phonon subsystem divided into the coherent active and the noise relaxation parts. The model proposed allows a qualitative description of experimental data.
Show AbstractTwo-wave polarization spectroscopy of nonlinear rotation and deformation of light polarization ellipse in crystals
Two-wave polarization spectroscopy of nonlinear rotation and deformation of light polarization ellipse in crystals
A.A. Golubkov, V.A. Makarov
Collinear interaction of two high-power randomly-polarized wades of different frequencies in nonlinear gyrotropic media has been examined. The potentialities of a spectroscopic investigation of the associated polarization effects offer much greater efficiency as compared to the spectroscopy of nonlinear optical activity.
Show AbstractStructural changes in water exposed to weak variable magnetic fields
Structural changes in water exposed to weak variable magnetic fields
V.F. Kiselev, A.M. Saletskii, L.P. Semikhina
Changes of dielectric loss, electrical conductivity, heat transfer coefficient, and supercooling are found in bidstilled water exposed to a weak variable magnetic field. The magnetic field affects charged protons, proton-containing groups in water, and their nuclear spins, inducing changes in the transition probabilities of these particles in the chains of the Bernal-Fowler hydrogen bonds. A prolonged exposure to the field results in structural changes of the hydrogen bond network. The newly-formed quasi-equilibrium macroscopic state of water takes a very long time (hours) to relax to the initial state.
Show AbstractSpatial correlation of pressure pulsations on the surface of a cylinder moving in water
Spatial correlation of pressure pulsations on the surface of a cylinder moving in water
F.V. Rozhin, O.S. Tonakanov, S.G. Mikhailov
The mutual correlation functions of pressure pulsations on the surface of a cylinder passed around by water flowing at an 0.5 m/s velocity are studied experimentally. It is shown that in the case of two small-size sensors spaced apart along the incident flow, the mutual correlation of pressure pulsations decreases exponentially. A law for approximating the experimental data is proposed and a difference from the planar case is demonstrated.
Show AbstractOn the modeling of inverse scattering problems in physical experiment
On the modeling of inverse scattering problems in physical experiment
A.V. Glazkov, E.Ya. Tagunov
A procedure for the physical modeling of the two-dimensional inverse scalar scattering problems studied in computer-aided diffraction tomography (CDT) is discussed and an experimental set-up designed for such a modeling is described. The reduction of a three-dimensional inverse problem to a two-dimensional one is achieved by using the regime of single-mode propagation of an acoustic wave in a flat waveguide. Various data acquisition schemes for the particular CDT reconstruction algorithms are suggested and discussed.
Show AbstractSix-quarks in neutron stars
Six-quarks in neutron stars
Yu.V. Kuz'min
The behavior of nuclear matter is considered from the standpoint of the discovery of six-quarks. The results are applied to calculations of parameters of neutron stars. It is shown that the maximum masses and radii of neutron stars decrease and that there may exist ultrahigh-density objects of very small masses. A new mechanism is proposed to explain explosions of supernovae of the first type. It is demonstrated that in the process of collapse a star passes through a stage of instability leading to an explosive release of energy.
Show AbstractA theoretical description of the recombination fluorescence of photosynthesizing organisms using the kinetic equation
A theoretical description of the recombination fluorescence of photosynthesizing organisms using the kinetic equation
V.N. Torgashin, A.K. Kukushkin
Consideration is given to a theoretical model of the initial stages of the primary processes of photosynthesis. A Master Equation system consisting of three equations is used. The solution, which has been obtained using the Laplace transform, describes the kinetics of recombination fluorescence as a sum of decaying exponents. The relation between the fluorescence parameters and the rate constants of transitions between the states of the system has been obtained.
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