On the accuracy of a onedimensional approach to the solution of kinetic equations with velocitydependent collision frequencies
The solution of many problems in lightinduced gas kinetics can be simplified significantly using quantum kinetic equations in the context of the socalled onedimensional approximation, in which the initial equations are averaged over transverse (relative to the direction of radiation) velocities. The errors introduced in such an approach are usually assumed to be small; however, this has been confirmed quantitatively only on the basis of the simplest (two and threelevel) particle models. We analyze the accuracy of the onedimensional approximation for multilevel particles quantitatively for the lightinduced drift (LID) effect in cesium atoms in the atmosphere of inert buffer gases. It is shown that in the case of the socalled “normal” LID, onedimensional kinetic equations can always be used instead of threedimensional equations without a risk of losing some important fine details in the dependence of the drift velocity on the radiation frequency. In the case of anomalous LID, the error of the onedimensional approximation is also insignificant, but it can be disregarded only in the case of light buffer particles. For comparable masses of resonant and buffer particles, the onedimensional approximation may give a noticeable error in determination of drift velocity amplitudes; however, the positions of drift velocity zerosmore »
 Authors:

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^{[1]}
 Russian Academy of Science, Institute of Automation and Electrometry, Siberian Branch (Russian Federation)
 Publication Date:
 OSTI Identifier:
 22309106
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Experimental and Theoretical Physics; Journal Volume: 119; Journal Issue: 5; Other Information: Copyright (c) 2014 Pleiades Publishing, Inc.; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; APPROXIMATIONS; CESIUM; KINETIC EQUATIONS; MATHEMATICAL SOLUTIONS; ONEDIMENSIONAL CALCULATIONS; PARTICLE MODELS