Эффекты поляризации остова ядра-мишени в ядерных процессах рассеяния
Эффекты поляризации остова ядра-мишени в ядерных процессах рассеяния
Ф.А. Живописцев
В работе на основе формализма квантовых функций Грина получены выражения для T-матриц с выделением членов, учитывающих эффект возбуждения остова ядра - мишени в процессе ядерного взаимодействия между нуклонами. Показано, что в газовом приближении можно построить итерационную схему последовательного учета частично-дырочных возбуждений остова ядра-мишени в ядерных процессах.
Show AbstractК теории явлений переноса по локализованным состояниям
К теории явлений переноса по локализованным состояниям
И.П. Звягин
Рассмотрена теория явлений переноса путем перескоков между локализованными состояниями в неупорядоченных полупроводниках. Получены выражения для плотности тока и плотности потока энергии при наличии в системе электрического поля и градиента температуры. Обсуждается температурная зависимость термоэдс в условиях, когда прыжковый механизм дает основной вклад.
Show AbstractК теории оптического поглощения в полупроводниках с глубокими уровнями в запрещенной зоне
К теории оптического поглощения в полупроводниках с глубокими уровнями в запрещенной зоне
В.М. Ярцев
Вычислено влияние взаимодействия электронов с акустическими и оптическими фононами на вид спектра поглощения в полупроводниках с одноименно заряженными примесными центрами.
Show AbstractDissipative structures in a model for a chemical reaction with diffusion
Dissipative structures in a model for a chemical reaction with diffusion
M.S. Polyakova
Spatially periodic stationary solutions (dissipative structures) are considered for a model of a chemical reaction with diffusion; relationships are obtained between the amplitude of the dissipative structure and the wavelength, and the stability is also examined.
Show AbstractSelf-excited oscillations in spatially distributed biogeocenoses
Self-excited oscillations in spatially distributed biogeocenoses
V.V. Alekseev
Equations are derived to describe the behavior of communities of animals and plants in space and time; it is shown that the population density function takes the form of traveling waves in the linear approximation if the shifts in the environment are neglected and if there is a Yolterra interaction between species in the predator-prey system. A uniform distribution of the population densities in space is stable if there is a closed circulation of material.
Show AbstractApplication of percolation theory to the jump conductivity of a disordered sehiconductor
Application of percolation theory to the jump conductivity of a disordered sehiconductor
I.P. Zvyagin
A percolation problem arises in calculating the jump conductivity of a disordered semiconductor, and this is considered as determination of the critical density of the bonds between centers ϑc. Exact limits are obtained for the critical mean bond density, and an approximation calculation is performed via the procedure that takes into account the energy dependence of the mean number of bonds for an individual center.
Show AbstractThe contribution of collective modes in the target nucleus to the imaginary part of the optical potential
The contribution of collective modes in the target nucleus to the imaginary part of the optical potential
F.A. Zhivopistsev and E.S. Rzhevskii
Angular and energy relationships are examined for the part of the optical potential resulting from inelastic processes involving excitation of the lower collective states of the target; a comparison is made with the nonlocal Perey- Buck potential.
Show AbstractQuarks in astrophysics
Quarks in astrophysics
D.D. Ivanenko, D.F. Kurdgelaidze, and N.I. Maksyukov
A study is made of the basic parameters (including mass and radius) for equilibrium quark configurations having central densities from 10^{19} to 10^{32} g/C m^3; it is found that such objects should have large gravitational mass defects. It is assumed that quarks can recombine into hyperons, and it is shown that the number of recombined quarks is of the order of the total number of quarks in a star, the ratio of the number of free quarks to the recombined ones being 10^{-6}.
Show AbstractNonlinear representations of the lie algebra for the lorentz group (nondegenerate series)
Nonlinear representations of the lie algebra for the lorentz group (nondegenerate series)
N.F. Nelipa and I.B. Chervyakov
Nonlinear representations are derived for the Lie algebra of the Lorentz group (nondegenerate series), and invariants of the representation are constructed; it is shown that the dimensions of the maximal irreducible representation are 6.
Show AbstractTheory of emission from a point charged particle moving in parallel electric and magnetic fields
Theory of emission from a point charged particle moving in parallel electric and magnetic fields
A.B. Kukanov
The charged point particle moves in steady homogeneous parallel electric and magnetic fields; an analytic expression is derived for the total radiation energy incorporating polarization effects. A particular case is considered for motion in a steady and homogeneous electric field.
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