2,495 research outputs found
Wave Functions and Energy Terms of the SCHR\"Odinger Equation with Two-Center Coulomb Plus Harmonic Oscillator Potential
Schr\"odinger equation for two center Coulomb plus harmonic oscillator
potential is solved by the method of ethalon equation at large intercenter
separations. Asymptotical expansions for energy term and wave function are
obtained in the analytical form.Comment: 4 pages, no figures, LaTeX, submitted to PR
Quantum tops as examples of commuting differential operators
We study the quantum analogs of tops on Lie algebras and
represented by differential operators.Comment: 24 p
Spectra of Doubly Heavy Quark Baryons
Baryons containing two heavy quarks are treated in the Born-Oppenheimer
approximation. Schr\"odinger equation for two center Coulomb plus harmonic
oscillator potential is solved by the method of ethalon equation at large
intercenter separations. Asymptotical expansions for energy term and wave
function are obtained in the analytical form. Using those formulas, the energy
spectra of doubly heavy baryons with various quark compositions are calculated
analytically.Comment: 19 pages, latex2e, published at PRC61(2000)04520
Electromagnetic field of a charge asymptotically approaching spherically symmetric black hole
We consider a test charged particle falling onto a Schwarzschild black hole
and evaluate its electromagnetic field. The Regge-Wheeler equation is solved
analytically by approximating the potential barrier with Dirac delta function
and rectangular barrier. We show that for asymptotically large time measured by
a distant observer the electromagnetic field approaches the spherically
symmetric electrostatic field exponentially fast. This implies that in the
region accessible to a distant observer the initial state of separated charge
and Schwarzschild black hole becomes asymptotically indistinguishable from the
Reisnner-Nordstr\"om solution. Implications of this result for models with
plasma accretion on black holes are discussed.7 aComment: 7 pages, 2 figure
"And there was no Need to Say Anything …": Silence in the System of Means of Expression of the Author's Position
The article presents the first attempt to systematically examine the status of the phenomenon of silence as one of the most important means of expressing the author's position in the novel "Noble Nest" using the method of slow reading. It analyzes the key scenes of Turgenev's text, and through them identifies the value-based positioning in the system of characters (the opposition between "religious humanism" and "Christian ethics"). The authors of the article show the process of creating perceptibility for the reader of the semantic residue by Turgenev in the picture of the directly depicted and spoken. This is designed to mark the transition of the characters beyond the boundaries of the concrete historical background through the nature of the word of art. In this way Turgenev created his own version of the "higher reality" in the "Noble Nest" and, accordingly, the field of cultural dialogue with the works of his great contemporaries-realists.В статье впервые системно рассматривается статус феномена безмолвия как одного из важнейших средств выражения авторской позиции в романе "Дворянское гнездо" с применением методики медленного чтения
Mechanisms of arsenic clustering in silicon
A model of arsenic clustering in silicon is proposed and analyzed. The main
feature of the proposed model is the assumption that negatively charged arsenic
complexes play a dominant role in the clustering process. To confirm this
assumption, electron density and concentration of impurity atoms incorporated
into the clusters are calculated as functions of the total arsenic
concentration. A number of the negatively charged clusters incorporating a
point defect and one or more arsenic atoms are investigated. It is shown that
for the doubly negatively charged clusters or for clusters incorporating more
than one arsenic atom the electron density reaches a maximum value and then
monotonically and slowly decreases as total arsenic concentration increases. In
the case of doubly negatively charged cluster incorporating two arsenic atoms,
the calculated electron density agrees well with the experimental data.
Agreement with the experiment confirms the conclusion that two arsenic atoms
participate in the cluster formation. Among all present models, the proposed
model of clustering by formation of doubly negatively charged cluster
incorporating two arsenic atoms gives the best fit to the experimental data and
can be used in simulation of high concentration arsenic diffusion.Comment: 13 pages, 4 figures. Revised and shortened version of the paper has
been published in Phys. Rev. B, Vol.74 (3), art. no. 035205 (2006
Electromagnetic radiation and electromagnetic self-force of a point charge in the vicinity of Schwarzschild black hole
Point charge, radially moving in the vicinity of a black hole is considered.
Electromagnetic field in wave zone and in the small neighbourhood of the charge
is calculated. Numerical results of the calculation of the spectrum of
electromagnetic radiation of the point charge are presented. Covariant approach
for the calculation of electromagnetic self-force is used for the case of the
slowly moving charge. Numerical results for the self-force in the case of slow
motion of the particle are obtained and compared to the results in literature.Comment: 5 pages, 3 figure
Analysis of litter mesofauna of Poltava region forest ecosystems
На основі досліджень підстилкової мезофауни 48 обстежених лісових біогеоценозів охарактеризовано закономірності формування угруповань безхребетних на рівні видів і родин. Проаналізовано ступінь подібності пробних ділянок за таксономічною структурою герпетобію. Виявлено чинники, які впливають на формування підстилкової мезофауни лісових біогеоценозів Полтавської області.На основе исследований подстилочное мезофауни 48 обследованных лесных экосистем охарактеризованы закономерности формирования группировок беспозвоночных на уровне видов и семей. Проанализирована степень сходства пробных участков по таксономической структуре герпетобию. Выявлены факторы, влияющие на формирование подстилочное мезофауни лесных экосистем Полтавской областиOn the basis of research of litter mesofauna of 48 forest biogeocenoses the regularities of invertebrate communities formation on the species and families levels are determined. The degree of similarity of test plots are analysed by taxonomic structure of the communities. The factors of the litter invertebrate communities formation in forest ecosystems of the Poltava region are revealed
Trophic structure of litter mesofauna: biomass differentiation between trophic levels
На основі досліджень підстилкової мезофауни чотирьох лісових біогеоценозів Полтавської області побудовано трофічно-вагові моделі угруповань безхребетних. Проаналізовано розподіл біомаси за трофічними рівнями, розмірну і таксономічну структуру окремих рівнів. Охарактеризовано відмінності та спільні риси трофічно-вагових моделей угруповань безхребетних. На основе исследований подстилочное мезофауни четырех лесных экосистем Полтавской области построено трофические-весовые модели группировок беспозвоночных. Проанализировано распределение био¬масы за трофическими уровнями, соразмерную и таксономическую структуру отдельных уровней. Охарактеризованы различия и общие черты трофические-весовых моделей группировок беспозвоночных.On the basis of research of litter mesofauna in four forest biogeocenoses of the Poltava region the trophic-weight models of invertebrate communities are creating. The biomass differentiation between trophic levels, weight and taxonomic structure of the separate levels are analysed. The differentiation and similarity of the trophic-weight models of litter invertebrate communities are discussed
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