Measurement of Lifetimes of Excited States of Na, Tl, In, Ga, Cu, Ag, Pb, and Bi by the Phase-Shift Method

Lifetimes of 13 upper states of optical-resonance transitions in selected metal atoms have been measured using the phase-shift method. Data were taken over a range of at least 12 of fluorescence intensity, to take into account the effects of radiation entrapment and exciting light scattering. The following results were obtained: Na 3p2P0 16.2 nsec, Tl 7s ²S12 7.65 nsec, Tl 6d²D32 6.9 nsec, In 6s ²S12 7.5 nsec, In 5d ²D32 7.9 nsec, In 5d ²D52 7.9 nsec, Ga 5s ²S12 7.6 nsec, Ga 4d2D 7.7 nsec, Cu 4p2P0 7.2 nsec, Ag 5p ²P120 6.7 nsec, Ag 5p ²P120 7.5 nsec, Pb 7s3P10 6.05 nsec, and Bi 7s ⁴P12 5.9 nsec. Estimated absolute accuracies vary between 3 and 7%.