The Optimal Pair of Rydberg Alkali-Metal Atoms in the Nonsymmetric Penning Ionization Processes

Optics and Spectroscopy - Features of Penning ionization in cold gaseous media of Rydberg alkali-metal atoms have been investigated. In contrast to the hydrogen atom, the corresponding...     

On accounting for the effect of particles of a condensed dispersed phase on radiant energy transfer in gaseous media

Questions concerning the formation of the optical properties of dense gaseous and plasma media in relation to the specific features of radiant energy transfer are considered. The integral equations describing the radiation trapping are investigated as a new class of generalized wave equations of Schrödinger type. Starting from the methods of quantum mechanics, original analytical and numerical approaches are suggested for solving problems of the radiative kinetics of both spatially homogeneous and inhomogeneous absorbing media containing dispersed particles. In terms of the quasi-classical approximation, two classes of reference problems for determination of phase factors are formulated. Solutions for a number of model problems are presented that demonstrate the efficiency of the methods developed.     

Reduced Doppler absorption profile in atomic and molecular beams

The formation of the Doppler absorption profile P(ν) upon optical excitation of particles in the volume of effusion or gas-dynamic atomic and molecular beams by laser light propagating in a direction orthogonal (reduced) to the beam axis is considered. The analytical expressions for P(ν) are obtained for different types of beams and the specific features of the reduced absorption profile are studied as functions of the beam parameters. The function P(ν) is shown to be considerably different from the standard Gaussian shape. It is demonstrated that the calculated absorption spectrum at the frequencies of the sodium resonance lines D _1,2 agrees well with experiment.     

Optimization of sub-Doppler absorption contour in gas-dynamic beams

The formation of the Doppler contour P _D(?) of absorption lines upon the excitation of particles in the volume of a gas-dynamic beam by light propagating in a direction orthogonal (reduced) to the beam axis is analyzed. Integral representations of P _D(?) are obtained for arbitrary relations between the nozzle outlet diameter D and the collimating aperture diameter B in the excitation region are obtained. An optimal configuration at which the reduced Doppler contour is the narrowest at a high density of beam particles is revealed to be B/D = 2.