On bremsstrahlung of photons in electron scattering from nuclei
On bremsstrahlung of photons in electron scattering from nuclei
A.I. El-Gauhari
A general expression has been obtained for the differential cross section of the bremsstrahlung process in electromagnetic scattering of unpolarized electrons from polarized nuclei with arbitrary spin accounting for circular polarization of $\gamma$-quanta. Consideration for the nucleus polarization in these processes opens up fresh opportunities for individual investigation of nuclear multipoles.
Show AbstractMorphological method of adaptive correction of image sensor array elements
Morphological method of adaptive correction of image sensor array elements
Yu.P. Pyt'ev, S.S. Zadorozhny
Morphological image analysis is used for sensor adaptive correction without any special testing in the process of actual image interpretation.
Show AbstractIntrinsic geometry of surfaces and spectra-evolutionary problem statement
Intrinsic geometry of surfaces and spectra-evolutionary problem statement
S.A. Zadadaev
The construction of spectra-evolutionary operators of the inverse scattering problem by the differentional geometry methods is proposed. The algorithm discussed follows the analogy between the surface structure equations in $E^3$ and the formalism of the inverse scattering problem method.
Show AbstractAbsorption of a high-power electromagnetic pulse of short duration by a dense plasma layer
Absorption of a high-power electromagnetic pulse of short duration by a dense plasma layer
L.V. Borodachev, P.A. Gofman
The numerical experiment method has been employed in the study of a collision-free regime of interaction of an ultra-short high-power laser pulse with a surface plasma layer of a condensed target. The use was made of the $(1\frac22)$-dimensional discrete kinetic model of a nonrelativistic plasma with an ion background in the Darwin approximation for self-consistent electromagnetic fields. The behavior of the skin layer plasma has been found to differ substantially from the linear theory predictions. The average value of energy of electrons is comparable with their oscillation energy. The particles distribution function is highly anisotropic and differs significantly from the Maxwellian distribution.
Show AbstractThree-wave mixing in stationary parametric holographic scattering: exact solution with depleted pumping
Three-wave mixing in stationary parametric holographic scattering: exact solution with depleted pumping
P.A. Prudkovskii, O.V. Skugarevskii, A.N. Penin
A three-wave model of parametric holographic scattering has been discussed. It is demonstrated that, under the assumption of scattering symmetry, an exact stationary solution with regard to depleted pumping can be obtained. The solution dependence on the initial phase difference of the three waves has been analyzed. An idea of certain experiments has been proposed for obtaining new information on photorefractive crystal parameters and the nature of seed radiation.
Show AbstractConditions of Boussinesq approximation applicability to the analysis of stationary medium convective stability
Conditions of Boussinesq approximation applicability to the analysis of stationary medium convective stability
A.V. Uvarov, A.I. Osipov
Analysis of a complete system of hydrodynamic equations that made it possible to obtain the applicability conditions of the Boussinesq approximation in the vicinity of the convective stability loss critical conditions has been carried out. It has been demonstrated that an intricate system of inequalities reduces to simple criteria determined mainly by the system characteristic dimensions. The criteria found in the literature that involve an unjustified narrowing of the field of the Boussinesq approximation application have been analyzed. The found criteria have been used for estimating the parameters of real systems, where the Boussinesq approximation holds.
Show AbstractTranslational nonequilibrium in shock wave front in argon
Translational nonequilibrium in shock wave front in argon
P.V. Kozlov, S.A. Losev, Yu.V. Romanenko
We have studied the influence of a non-Maxwellian velocity distribution of gas particles in the front of a shock wave on the mechanism of gas excitation and emission. Shock wave emission in a H$_2$:Ar mixture with a 1:99 concentration ratio has been studied experimentally at M=6 and a mechanism has been proposed for this emission. It is shown that the emission in these conditions is purely nonequilibrium. The importance of consideration of the non-Maxwellian distribution in the course of exothermal reactions in a gas has been emphasized.
Show AbstractStructural features of Al, Ti, Pd, and Ta films obtained in discharge with oscillating electrons
Structural features of Al, Ti, Pd, and Ta films obtained in discharge with oscillating electrons
V.V. Bibikova, E.V. Likhushina, S.V. Sveshnikov, G.V. Smirnitskaya
The structure of thin AI, Ti, Pd, and Ta films deposited on glass substrates in discharge with oscillating electrons in two discharge modes (different pressures and discharge currents) has been studied. Deposition and particle flow rates have been determined. The content of Kr in the films was found to be of the order of several tenths of percent. The structure studies have shown that the films had a pronounced texture; the diffraction pattern distorted in some directions was evidence of packing defects. The structure of light metal (Al and Ti) films was shown to depend on discharge conditions; no such dependence was observed for heavy metals (Pd and Ta). All films prepared in mode II were less defective than films prepared in mode I.
Show AbstractStrong localization of current carriers in multilayer InAs/GaAs structures with quantum dots
Strong localization of current carriers in multilayer InAs/GaAs structures with quantum dots
V.A. Kul'bachinskii, V.G. Kytin, R.A. Lunin, A.V. Golikov, A.V. Demin, I.G. Malkina, B.N. Zvonkov, Yu.N. Saf'yanov
The transport and optical properties of $p$- and $n$-type lnAs/GaAs multilayer structures with quantum dots have been studied depending on the amount of deposited InAs. Indium arsenide quantum dots in GaAs have been found to form two-dimensional electronic or hole layers generating Shubnikov-de Haas oscillations. The experimental temperature dependences of resistance in the $[110]$ and $[\bar{1}10]$ directions (the temperature range of 1.6-300 K) have shown the resistance to be anisotropic. Experiment evidences that electric current carriers become localized as temperature decreases. According to the photoluminescence spectral data, light emitted in the plane of the structure is polarized.
Show AbstractA M$\stackrel{..}{o}$ssbauer study of atomic distribution in alloys $\beta$-Mn$_{18}$Sn$_{2-x}$Fe$_x$
A M$\stackrel{..}{o}$ssbauer study of atomic distribution in alloys $\beta$-Mn$_{18}$Sn$_{2-x}$Fe$_x$
V.S. Rusakov, A.S. Ilyushin, A.S. Vinogradova, I.A. Nikanorova
The atomic distribution in $\beta$-Mn$_{18}$Sn$_{2-x}$Fe$_x$ ($x=0\div2$) alloys has been studied by the $^{57}$Fe M$\stackrel{..}{o}$ssbauer spectroscopy. The earlier suggestion that the $8(c)$ sites in the $\beta$-Mn structure are favoured by iron atoms has been substantiated. Annealing was found to increase the degree of long-range order in the arrangement of iron atoms with respect to the $8(c)$ sites in the $\beta$-Mn structure. The presence of tin atoms in the $\beta$-Mn structure had virtually no effect on the degree of long-range order or iron atoms.
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