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Thermalization of velocity-selected excited-state populations by resonance exchange collisions and radiation trapping
Published
Author(s)
J Huennekens, A Allegrini, Zeina J. Kubarych, R Sagle, R K. Namiotka
Abstract
Populations of excited atoms that all have the same z component of velocity can be produced by pumping a vapor with a narrow-band laser. This velocity-selected population is then thermalized by velocity-changing collisions. However, in a pure vapor, even at low densities where velocity-changing collisions can be ignored, the mechanisms of radiation trapping and resonance exchange collisions can still lead to substantial thermalization of excited-atom velocity distributions. In this paper, we present data demonstrating these effects. We compare our data with results from a simple model of these processes. The model is in qualitative agreement with the experimental results.
Huennekens, J.
, Allegrini, A.
, Kubarych, Z.
, Sagle, R.
and Namiotka, R.
(1995),
Thermalization of velocity-selected excited-state populations by resonance exchange collisions and radiation trapping, Physical Review
(Accessed October 10, 2025)