Journal of Physics B Atomic and Molecular Physics

Fine-structure transitions in Rb(5P) induced by H2and N2molecules

J.‐M. Mestdagh, P de Pujo, J. Cuvellier, A Binet, P. R. Fournier, J. Berlande

Published Feb 28, 1982• 14 citations

Abstract

The energy dependence and the absolute value of the cross section for the P 1/2 to P 3/2 fine-structure transition (FST) in Rb(5P) induced by H 2 or N 2 molecules and He atoms has been measured for the first time in a crossed-beam apparatus. The results for He, in excellent agreement with previous experimental data, are used for comparing atomic and molecular target behaviour with regard to FST processes in heavy alkalis. One observes much larger cross sections for H 2 and N 2 at low energies with a much weaker energy dependence. Theoretical work suggests two seemingly competing mechanisms for including large FST cross sections for molecular targets. One, involving an intermediate ionic complex, accounts for the general trend (absolute value and energy dependence) of the experimental data for N 2 while the other, recently suggested by Hickman seems to play the major role when H 2 is the target.

DOI: 10.1088/0022-3700/15/4/017

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