The relativistic equations of motion of the spin and charge of a Dirac particle, with an anomal magnetic moment, in arbitrary applied electrom agnetic fields are derived within the framework of the covariant form alism of oneparticle quantum mechanics. Equations, which have the same form as the classical equations of motion of a charge and as the Bargmann - Michel - Telegdi spin equations of motion, are obtained in the zero approximation in ћ.
Show AbstractAn explicit covariant expression for the probabilities of transitions in the quantum field theory in terms of elements of a unitary scattering matrix, free of previously encountered inconsistencies, is pointed out.
Show AbstractThe chain of N.N. Bogolyubov equations for density matrices is used for determining the one-particle density matrix with allowance for correlations. The question of the effective interaction potential and of its utilization in the theory of quantum crystals is discussed.
Show AbstractA method previously suggested by the authors for investigating the primary contributions to the asymptotic behavior of apical functions of the quantum field theory Is used for calculating, in non - abelian gage theories, of the asymptotic behavior of the singlet and non-singlet form factors of scalar particles in the first six orders of the theory of perturbations.
Show AbstractExperiments on the vibrational excitation of molecules from different rotational states are described. The role of rotational relaxation in the course of multiquantum excitation of molecules is analyzed. It is shown that rotational relaxation has little effect on the absorption of powerful IR radiation by multiatomic molecules. It is concluded that molecules, in many rotational states, are effectively excited to high vibrational levels.
Show AbstractThe article presents theoretical and experimental results confirming the feasibility of experimental observation of electrical dipole resonance (EDR) in gases. The existence of this phenomenon makes it possible to observe quantum transitions between Stark sublevels, corresponding to different orientation of the electrical dipole moment of the molecule in an applied electrical field. The EDR p henomenon is analyzed theoretically for a gas consisting of symmetrical-top type molecules with an electrical dipole moment. The experimental observation of EDR was performed with gaseous CH$_3$F and CH$_3$CN.
Show AbstractA new method for attaining steady operation of systems operating with resonance temperature stabilization is examined. For this purpose selfoscillations with continuously rising frequency are excited in the system; this ensures maintaining the required amplitude of stress in the ferroceramic element during the entire period of its heating. Experimental results are presented.
Show AbstractThe shift of atomic spectral lines, produced by electrons and by neutral atoms in inequilibrium, partially ionized plasma is analyzed in the shock approximation. Expressions for variable width and shift, valid both in the equilibrium and nonequilibrium cases, are presented. The electron shift, with allowance for all the possible transitions from the n, m levels for alocally - equilibrium electron distribution is calculated. The shift of emission lines due to resonant dipole-dipole interaction is also calculated. It is shown that the line shift in resonant interaction is of the same order of magnitude, as its width, and should be considered in determining the line shape.
Show AbstractThis paper describes a study of the temperature dependence of the magnetization, paramagnetic susceptibility, and the electrical resistivity of the Cu$_x$ Co$_{1-x}$ Cr$_2$ S$_4$ polycrystalline spinel system. It was found that compositions with 0.5 < x < 1 are ferromagnetic semiconductors with Curie points above room temperature, with anomal location of ferro- and paramagnetic Curie points and with blue shift of the width of the forbidden zone.
Show AbstractExperimental data on the kinematics of the drift and compensating currents, as well as on dynamics of the gradient flow were obtained under laboratory conditions, simulating shelf regions of the sea. It was established that, for developed wind currents, arising in a water tunnel, there exists a transition layer between the drift and gradient currents, where the effect of the factors inducing these currents balances or nearly balances out. Here the gradient current can, in the first approximation, be treated as flow between two parallel walls.
Show AbstractThe dependence of the principal magnetic characteristics,i.e.Is,Ir,Kp end Нс on the packing density p of particles in a specimen at p~0.02-0.6 is investigated with specimens of highly - dispersed iron specimens, obtained electrochemically and differing by the dimensions of particles, lumps, and concentration of the magnetic phase. It was found that there exists a critical packing density p$_cr$ near which particles fracture, with resultant reduction in the anisotropy of their shape. This results in a steep change in the structure - sensitive magnetic parameters Ir, Kp end Нс of the specimens in the vicinity of p$_cr$. It was established that at p < p$_cr$ the value of Нс is the greater, the higher the value of Cm in the powder, and the greater the size D of the lumps D of the starting particles.
Show AbstractA mass spectroscope was used for investigating the nature of protondonor centers on a real germanium surface. It was shown that the source of protons are water molecules, adsorbed on surfaces of coordinate - unsaturated atoms.
Show AbstractThe paper is concerned with the concentration reduction in the absorptive capacity of a number of molecules of pigments. It is shown that this process is not always associated with the formation of their colorless forms. Study of the temperature behavior of concentrated pigment solutions, as well as of their luminescense spectra points to the fact that the reason for reduction in the absorptive capacity is frequently the association of the molecules of the solute. Here partial decoloration of pigment solutions with increase in its concentration is a rather widespread process and manifests itself in the association not only of uniform, but also of nonuniform molecules of pigments.
Show AbstractThe effect of thermal noise on transition from roll convection to turbulence is analyzed within the framework of the three - mode Lorenz model. Starting with a system of hydrodynamic equations with random sources, in the form suggested by Landau and Lifshits, a system of Langevin equations, corresponding to the Lorenz system is obtained. The Langevin equations solved by computer and it is found that there exists an intermediate stage in transition from convection to turbulence - a regime of periodic, gradually tending to stoichastic,fluctuations of flow and temperature, which branches off softly from the steady convection mode at a certain, noise - level depended value of the temperature gradient.
Show AbstractMetrics of spaces with rotation and uniform deformation in the absence of the field of the gravitation - inertial force are obtained without resort to Einstein's equations.
Show AbstractThe radiation from an arbitrarily oriented dipole, moving uniformly in a medium, the dielectric constant of which changes instantaneously in time is considered. The spectral and angular distribution of radiation is calculated. The limits of applicability of the results are pointed out.
Show AbstractThe experimentally detected quenching of cathode luminescence of heterogeneous mixtures of ZnO with polymethylphenylsiloxane by oxygen and nitrogen plasma is related to changes in the luminescence properties of the polycrystalline ZnO. This effect is attributed to concentration quenching of luminescence and amorphization of ZnO upon enrichment of the surface by cations and atoms of the metal, as a result of volumetric diffusion, which is stimulated by Auger neutralization of positive plasma ions with energies of ~10 eV on the surface of the crystal lattice.
Show AbstractВ диэлектрических резонаторах из монокристаллического титаната стронция при температуре жидкого гелия обнаружено нелинейное возрастание диэлектрических потерь с увеличением амплитуды поля возбуждаемых колебаний. Измерения на частотах 0,5—1 ГГц показали, что нелинейность потерь проявляется в слабых полях порядка 1 В/см и, вероятно, связана с релаксацией, объемного заряда в сегнетоэлектрике.
Show AbstractThe paper presents certain results of a study of the structural features of thin tungsten films, sputtered by an oscillating - electrons discharge. The sputtering was onto two types of substrate: glass and NaCl. The suggested sputtering system makes it possible to sputter and investigate several films at the same time. The chemical composition of the sputtered metals as well as of the resulting films is analyzed by Auger spectroscopy. The film structure is determined, and the lattice parameters are calculated with an aid of a transmission electron microscope.
Show AbstractSpectra of combinatorial scattering of quartz crystals with elevated flaw content are investigated, and it is shown that point-type flows do not change the nature of phonon - phonon interactions, inherent to ordinary natural crystals.Significant changes in the temperature dependence of the frequency and linewidth of 466 cm$^{-1}$ lines of combinatorial scattering spectra were observed for a specimen, containing a large quantity of the amorphous phase.
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