Lifetime measurement of the 6s level of rubidium -: art. no. 012502

We present a lifetime measurement of the 6s level of rubidium. We use a time-correlated single-photon counting technique on two different samples of rubidium atoms, a vapor cell with variable rubidium density, and a sample of atoms confined and cooled in a magneto-optical trap. The 5P(1/2) level serves as the resonant intermediate step for the two-step excitation to the 6s level. We detect the decay of the 6s level through the cascade fluorescence of the 5P(3/2) level at 780 nm. The two samples have different systematic effects, but we obtain consistent results that averaged give a lifetime of 45.57 +/- 0.17 ns.