Abstract
Using the inherent timing stability of pulses from a mode-locked laser, we measure the cesium excited-state lifetime. An initial pump pulse excites cesium atoms in two counterpropagating atomic beams to the level. A subsequent synchronized probe pulse ionizes atoms that remain in the excited state and the photoions are collected and counted. By selecting pump pulses that vary in time with respect to the probe pulses, we obtain a sampling of the excited-state population in time, resulting in a lifetime value of 30.462(46) ns. The measurement uncertainty (0.15%) is slightly larger than our previous report of 0.12% [J. F. Sell et al., Phys. Rev. A 84, 010501(R) (2011)] due to the inclusion of additional data and systematic errors. In this follow-up paper we present details of the primary systematic errors encountered in the measurement, which include atomic motion within the intensity profiles of the laser beams, quantum beating in the photoion signal, and radiation trapping. Improvements to further reduce the experimental uncertainty are also discussed.
6 More- Received 27 May 2014
DOI:https://doi.org/10.1103/PhysRevA.91.012506
Published by the American Physical Society