Lifetime measurement of the 1s5metastable state of argon and krypton with a magneto-optical trap

Abstract

The natural decay rates of the 1${\mathit{s}}_5$[${\mathit{np}}^5$(n+1)s${,}^3$ ${\mathit{P}}_2$] metastable state of argon and krypton are experimentally determined using a magneto-optical trap. The method to determine the lifetime of a metastable state from a fluorescence decay measurement is described. The obtained lifetimes are ${38}_{\mathrm{-}5}^{+8\mathrm{}}$ s for argon and ${39}_{\mathrm{-}4}^{+5\mathrm{}}$ s for krypton.