Lifetimes of theΞ−andΞ0Hyperons

Abstract

A sample of 794 ${\Xi }^{-}$ hyperons and 101 ${\Xi }^0$ hyperons has been used in a determination of the ${\Xi }^{-}$ and ${\Xi }^0$ lifetimes. We find ${\tau }_{{\Xi }^{-}}=1.69\mathrm{}\pm 0.07\times {10}^{-10\mathrm{}}$ sec and ${\tau }_{{\Xi }^0}={{2.5}_{-0.3\mathrm{}}}^{+0.4\mathrm{}}\times {10}^{-10\mathrm{}}$ sec. The ratio of the ${\Xi }^0$ decay rate to the ${\Xi }^{-}$ decay rate, $\frac{{\lambda }_{{\Xi }^0}}{{\lambda }_{{\Xi }^{-}}}=0.68\mathrm{}\pm 0.10$, is within two standard deviations of the $\left|\Delta T\right|=\frac{1}{2}$ prediction of 0.5.