Lifetime of the(6s26p7s)P1

Abstract

Hanle-effect studies have been made in the (6s 2 6p7s) ^Pi 0 state of lead. Pb 208 atoms were excited to this state by 2022-A lead resonance light, and the 5005-A cross-fluorescent line from this state was detected. The width of the level-crossing signal corresponds to a lifetime for this state of 4.99(15)X10~9 sec, where the quoted uncertainty is three times the standard deviation. This value is a factor of 4 longer than the value calculated from the oscillator strengths of Corliss and Bozman.