HYDROGEN AND HELIUM PRESSURE BROADENING OF H2S BETWEEN 2 AND 600 K

The hydrogen (H-2) and helium (He) pressure-broadening cross sections of the 1(10) <-- 1(01) transition of HS have been measured between 2 and 600 K. This more than two decade range in temperature makes possible the consideration of these collisions as a spectroscopic process in which the translational energy plays the role of the spectroscopic variable. Although in the semiclassical region the pressure broadening due to Hz and He is similar, at low temperature large qualitative differences occur, resulting in almost an order of magnitude larger cross section for collisions with Hz below 10 K. (C) 1994 Academic Press, Inc.