Measurements of ${\mathrm{\Omega }}^{-}$ Branching Fractions

Using $e^{+}{e}^{-}$ annihilation data taken at the CESR collider with the CLEO-c detector, measurements of two main ${\mathrm{\Omega }}^{-}$ branching fractions have been made using the reaction $\psi (2S)\to {\mathrm{\Omega }}^{-}{\bar{\mathrm{\Omega }}}^{+}$, hyperon pair production at $\sqrt{s}=3.69$~GeV, the peak of the $\psi (2S)$ resonance. ${\mathrm{\Omega }}^{-}$ decay channels are identified through momentum distributions of charged particles, and systematics of the ${\mathrm{\Omega }}^{-}$ branching fractions have been studied. The result gives: $$\mathcal{B}$(\Omega^- \to \Lambda^0 K^-) = (68.9\pm9.5\pm4.3)%$,and$ $\mathcal{B}$(\Omega^- \to \Xi^0 \pi^-) = (19.0\pm4.0\pm1.2)%$.