Precision measurement of the metastable 6s

Abstract

Using a magneto-optical trap to isolate an isotopically pure sample of xenon, we determine the metastable 6s [3/2${]}_{2}$ state lifetime by measuring the rate of VUV emisson due to magnetic quadrupole decay. We find lifetimes of 42.9(9) s and 42.4(13) s for $^{132}\mathrm{Xe}$ and $^{136}\mathrm{Xe}$, respectively (1\ensuremath{\sigma} uncertainties). These values are less than half the theoretical predictions. We also find that nuclear-spin-induced decay produces a much shorter metastable lifetime in $^{129}\mathrm{Xe}$.