Radiative-lifetime and Landé-factor measurements of the Se I 4p35s 5S2 level using pulsed laser spectroscopy

Abstract

First laser spectroscopic investigations on atomic selenium are reported. Natural selenium was thermally dissociated in a quartz resonance cell keeping the background pressure of abundant selenium molecules low by differential heating. The 4p~5s~S2 level was excited by frequency-tripled pulsed-dye laser radiation at 207 nm. From time-resolved recordings of the fluorescence decay at 216 nm a natural radiative lifetime of 493(15) ns was determined, while quantum-beat and optical double-resonance measurements in an extemal magnetic field yielded gj = 2.0004(10) for the Land6 factor. The results are compared with previous theoretical and experimental data.