Optical pumping of metastable5S oxygen

Abstract
An optical pumping experiment on the metastable 5S state of atomic oxygen is reported. Metastable atoms were excited by a discharge in a low-pressure mixture of gaseous oxygen and helium. Both a discharge lamp and a CW dye laser at lambda =7773AA were successively used as optical pumping sources. The extrapolated magnetic resonance linewidth is practically equal to the radiative natural linewidth of 0.6 mG ( tau approximately=0.18 ms).