SovietRxiv · Open Access in English
Rediscovering the Soviet scientific archive, in English
25357 full-text translations 14926 English PDFs 22539 abstracts
Showing 50 of 2226 papers in Physics
The paper studies the direct and inverse scattering problem for the one-dimensional Schrödinger operator on the whole line with an integrable potential satisfying a first moment condition. It derives analytic, continuity, unitarity, and residue properties of the scattering matrix, relates its entrie…
This paper applies Bogolyubov’s variational principle to a more general superconducting Hamiltonian that includes, in addition to pairing of electrons with opposite momenta and spins, interaction terms with nonzero momentum transfer. After a canonical transformation to quasiparticle operators, the t…
This paper applies S. M. Lozinskii’s linearized error estimate for Adams numerical integration methods to the basic system of exterior ballistics, describing projectile motion under gravity and air resistance. It derives bounds for the matricant of the Jacobi matrix and for the integral terms enteri…
This note studies the spectrum of a self-adjoint Schrödinger operator for atoms and ions with Coulomb interactions, including the effect of nuclear motion through mixed second-derivative terms. Using variational quadratic forms, auxiliary reduced operators, and criteria for the limiting spectrum, it…
This paper develops a spectral representation for Chandrasekhar’s axially symmetric turbulence in an incompressible viscous fluid subject to a constant vertical temperature gradient. Neglecting third-order correlation moments, it formulates the correlation equations for velocity, temperature, and pr…
This paper examines the absorption and luminescence of light by a quantum linear harmonic oscillator in order to compare its predictions with those of classical electrodynamics. Using Einstein transition probabilities for neighboring oscillator levels, including induced emission as negative absorpti…
This note develops a probabilistic treatment of radiation diffusion in a plane layer of finite optical thickness with isotropic scattering and photon survival probability. Using Ambartsumian’s method of adding layers, it derives equations for the resolvent of the transfer integral equation and shows…
This paper derives variational expressions for the energy and effective mass of an exciton in an ionic crystal while accounting for inertial polarization of the lattice. Starting from an exciton phonon Hamiltonian, the author uses Feynman path integrals to eliminate the phonon variables and applies …
This study examines how adsorbed vapor layers affect the surface electrical conductivity of optical quartz, with relevance to surface charge formation and adhesion phenomena. Using a quartz vacuum apparatus and electrometer measurements, the authors measured conductivity during adsorption of water, …
This paper examines whether long-duration phosphorescence in organic luminophores can arise from more than one metastable emitting level, contrary to the common extension of single-level fluorescence theory to phosphorescence. The authors review earlier evidence from nonexponential decay and wavelen…
This paper experimentally investigates the rate of thermal oxygen dissociation behind strong shock waves produced in a shock tube. The gas state was inferred from ultraviolet absorption in selected regions of the Schumann-Runge system, allowing the temperature distribution immediately behind the sho…
This paper develops formulas for X-ray diffraction from polymer regions composed of long, parallel chain molecules forming an axial texture. It treats three idealized degrees of order: complete three-dimensional order, free rotation of chains with regular axial shifts, and one-dimensional diffractio…
This paper examines whether Raman scattering and fluorescence can be observed and distinguished within an absorption band, using solutions of 4-nitro-4′-aminostilbene and 4-nitro-4′-dimethylaminostilbene in several solvents. The authors compare absorption and fluorescence maxima, fluorescence yields…
This paper analyzes the electromagnetic radiation produced by a point charge moving uniformly along the axis of a circular aperture in an infinite ideally conducting plane, in the nonrelativistic limit. The field is represented as the sum of ordinary transition radiation and the radiation associated…
The paper formulates a statistical variational principle for a system of Fermi particles with pair interactions, extending Bogolyubov’s zero-temperature variational method to nonzero temperatures. Using a canonical transformation to quasiparticle amplitudes as variational parameters and Bogolyubov’s…
The paper investigates whether a reported conversion line near 1909 keV in the decay of La140 corresponds to a transition in Ce140 between a 0+ excited state and the 0+ ground state. The authors measured the gamma spectrum near 1900 keV with a ritron-type gamma spectrometer and examined the hard con…
This study examines the fine structure of titanium K absorption spectra in a series of titanates, including compounds with perovskite and ilmenite type structures, barium metatitanate and tetratitanate, zinc titanate, and rutile. Using a focusing X ray tube spectrograph and absorbers of varying thic…
This paper investigates anisotropy in the longitudinal and transverse galvanomagnetic effects of an ultrapure n-type germanium single crystal along the principal crystallographic directions [100], [110], and [111] within the (110) plane. To avoid differences between separate specimens, the authors u…
The paper derives sufficient conditions for the formation of a stigmatic image in the paraxial region of electron optical systems whose principal trajectory, and hence optical axis, is curvilinear. Using curvilinear coordinates tied to the principal trajectory, the author expands nearby electron pat…
This paper examines why superconductivity is not observed in ferromagnetic metals using the microscopic theories of superconductivity and the s-d exchange model of ferromagnetism. The authors argue that exchange interaction splits the Fermi surfaces for conduction electrons with opposite spin projec…
This paper analyzes radiation emitted by electrons rotating in a uniform magnetic field, with emphasis on high harmonics relevant to solar and cosmic radio sources. Starting from the single-electron spectrum, the author derives angle-averaged emissivities for ordinary and extraordinary polarizations…
This paper examines rapid temporal changes in helium line intensities in nonstationary stellar spectra, especially lines connected with the metastable helium level 2 triplet S and the solar 10830 angstrom absorption line. It develops a simple kinetic model for a thin stellar shell in which electron …
This paper investigates phase transformations in water under dynamic compression by strong shock waves over pressures from 20,000 to 800,000 atm. The authors determine shock-wave and mass velocities using electrical-contact gauges and known aluminum screen Hugoniots, then derive pressure and density…
This note addresses radiation diffusion in a semi-infinite plane medium with spherical scattering indicatrix, following Sobolev’s reduction of luminosity problems to an integral equation for the function Phi of optical depth. Using one-sided Laplace transforms, inversion, and contour integration, th…
The paper examines a discrepancy between calculated and measured values of the Panofsky ratio in pion absorption and considers whether it may be resolved by hypothesizing a second neutral pion with isotopic spin zero. The authors analyze consequences of this hypothesis for charge-exchange scattering…
This paper derives an asymptotic representation for the solution of the Thomas-Fermi equation governing the statistical electron distribution in an atom, subject to the standard boundary conditions at the origin and infinity. By transforming the dependent variable around the known particular solutio…
This paper investigates the spontaneous fission of thorium-232 as a means of constraining the stability of bound nucleons against decay into lighter particles. The authors developed a higher-sensitivity rare-event detection method using large proportional counters coated with purified thorium oxide,…
Ivanenko and Brodsky formulate a nonlinear generalization of the Dirac equation for a quantized spinor field, using four-fermion invariants motivated by a universal Fermi interaction and a single world spinor. By imposing anticommutation relations and invariance under Lorentz, Pauli, isotopic, and r…
This paper examines how surface states in a semiconductor can affect the electrostatic component of adhesion at a metal, semiconductor contact. Using a phenomenological model with donor and acceptor surface levels, based on the Bardeen and Brattain scheme, the authors derive relations between contac…
This paper develops a statistical theory of fluctuations in the sensitivity of crystals in nuclear photographic emulsions, arguing that observed fluctuations in particle track density are more plausibly due to crystal sensitivity variations than to ionization fluctuations. The authors model sensitiz…
This paper describes the adaptation of an electron-optical shadow, or schlieren, method for studying electric field and potential distributions in semiconductor p-n junctions. Using a coordinate mesh as a field indicator, a 50 kV electron beam, and differential photographic recording of distorted an…
This paper examines the size distribution of Barkhausen magnetization-reversal jumps, questioning the prevailing view that smaller jumps always occur more frequently and that the distribution decreases monotonically with jump size. Using an apparatus with improved sensitivity to about 10^-7 CGSM, ac…
This paper examines nonlinear behavior near the center of a strong explosion when linearized perturbation solutions become singular and fail to satisfy the central boundary condition. Using a one-dimensional ideal-gas explosion with adiabatic exponent 7 as a model, it compares regimes of density per…
This paper addresses the construction of equilibrium correlation functions for systems of identical charged particles, especially where earlier perturbative expansions led to divergent integrals at small or large distances. Starting from Bogolyubov’s hierarchy, the authors separate the self-consiste…
This note studies the large time asymptotic behavior of solutions to the Cauchy problem for the nonlinear equation of unsteady gas filtration, equivalent to a heat equation with power law thermal conductivity. Using the invariance of the equation under shifts of mass, position, and time, the authors…
This paper presents a simplified derivation of virial expansions for nonideal gases in both classical and quantum statistics. Starting from the grand canonical expansion in powers of activity, it uses Cauchy’s theorem and residue methods to invert the density activity relation and obtain the general…
This paper analyzes how shock waves are amplified when they interact with a flame front in a combustible gas. The authors treat the flame front approximately as a contact discontinuity for refraction and reflection of weak shock waves, then model the additional strengthening caused by shock compress…
This paper derives jump conditions for shock waves in an ideal compressible fluid within general relativity, using integral forms of four-momentum and mass conservation together with Einstein’s equations. Applying Sedov’s method to a moving surface of strong discontinuity, it obtains general relatio…
This paper examines whether the plasma of a low-current direct-current arc between carbon electrodes at atmospheric pressure in inert gases is in thermal equilibrium. The authors measure absolute and relative intensities and radial distributions of selected hydrogen, helium, and neon spectral lines,…
This paper analyzes equilibrium ionization in systems where thermionic emission from carbon dust particles is significant, with attention to multiple positive and negative charging of the particles. It formulates the charge balance and particle conservation equations for identical grains and express…
This paper develops a theory of stationary laminar chain-thermal flame propagation in which both heat and active chain centers are transported from hot reaction zones into colder regions. A simplified chain mechanism is coupled to heat balance and active-center diffusion equations, then reduced thro…
This paper develops a general treatment of equilibrium ionization for homogeneous particles that may carry positive or negative charges, ranging from atoms to macroscopic particles. Using the law of mass action together with charge and mass conservation, it derives a general ionization equation and …
A method is presented for determining absolute oscillator strengths of resonance absorption lines without requiring a vapor column of known concentration, a limitation that affects conventional absorption and hook methods for reactive or difficult-to-evaporate elements. The approach combines simulta…
This study investigates the mechanism by which binary mixtures of inert gases separate in a direct-current discharge, focusing on whether separation is primarily due to ion transport toward the cathode or neutral atom motion toward the anode. Gas samples were withdrawn from near-electrode regions of…
This paper develops a thermodynamic fluctuation theory of anomalous magnetic scattering of thermal neutrons near the Curie point of ferromagnets and antiferromagnets. Starting from the Born approximation, it derives expressions for the differential scattering cross section in terms of Fourier compon…
This paper studies the inverse scattering problem for a two-equation matrix Schrödinger system on the half-axis with a singular tensor term of order x^{-2}, motivated by the deuteron problem with tensor forces. It establishes spectral properties for the associated boundary-value problem, defines the…
The paper examines how spatially stable striations form in the positive column of a pulsed hydrogen discharge at pressures of 2.8 to 4.5 mm Hg. Using repeated rectangular microsecond current pulses and varying pulse duration, the authors photograph successive stages of discharge development and meas…
This note treats spatial steady potential flows of a relativistic barotropic gas without friction or heat conduction, using the pseudovelocity potential and the relativistic Bernoulli relation. In Lorentz coordinates the author derives the governing differential equation for the ordinary velocity po…
The paper studies one-dimensional adiabatic propagation of disturbances in a half-space medium whose stress depends nonlinearly on deformation and temperature, under a constant compressive stress applied at the boundary. Using Sedov’s dimensional and similarity method, the governing equations, therm…
This paper examines heat transfer across the visible boundary observed between normal and superfluid liquid helium under a steady heat flux, where experiments showed jumps in temperature and density despite the ordinarily second-order character of the transition. A phenomenological model is develope…
