Study of the Visible Fluorescence of Gaseous UF₆

Abstract

The visible fluorescence from the forbidden Ã-X̃ absorption band (340–410 nm) of gaseous UF₆ has been observed previously by difrefent authors [1, 2, 3]. The lifetime at p=0 turns out to be considerably shorter than that estimated from the integrated absorption spectrum, indicating a non-radiative process as the agent mainly responsible for unimolecular decay. In addition, a quenching rate at room temperature corresponding to a high number of collisions has been measured. We report here further investigations on gaseous UF₆ excited at 374 and 270 nm. As regards the excitation at 374 nm, we have studied the dependence of the fluorescence decay time on pressure at different temperatures.