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Bulletin of the American Physical Society

Two-color photoionization of alkali-metals

M. Marinescu, H. R. Sadeghpour, A. Dalgarno

Published May 1, 1993• 0 citations
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Abstract

Two-color two-photon photoionization of hydrogen and alkali atoms is presented. The method based on a perturbation expansion is valid for low to moderately intense radiation fields. Three processes are considered leading to the photoionization. For the first process both photons are below threshold, and for the second process one photon is above the threshold with an energy less than the final energy of the photoelectron. The last process is identical to the continuum Raman (Compton) scattering where the first photon is absorbed high in the continuum and the second low energy photon is scattered. Photoionization cross sections of hydrogen and the alkali atoms are given as functions of the first photon energy and the photoelectron energy.

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