Measurements of ${\Xi }_c^{+}$ Branching Ratios

Abstract

Using data collected by the fixed target Fermilab experiment FOCUS, we measure the branching ratios of the Cabibbo favored decays ${\Xi }_c^{+}\to {\Sigma }^{+}{K}^{-}{\pi }^{+}$, ${\Xi }_c^{+}\to {\Sigma }^{+}{\bar{K}}^{\ast }(892{)}^0$, and ${\Xi }_c^{+}\to {\Lambda }^0{K}^{-}{\pi }^{+}{\pi }^{+}$ relative to ${\Xi }_c^{+}\to {\Xi }^{-}{\pi }^{+}{\pi }^{+}$ to be $0.91\pm 0.11\pm 0.04$, $0.78\pm 0.16\pm 0.06$, and $0.28\pm 0.06\pm 0.06$, respectively. We report the first observation of the Cabibbo suppressed decay ${\Xi }_c^{+}\to {\Sigma }^{+}{K}^{+}{K}^{-}$ and we measure the branching ratio relative to ${\Xi }_c^{+}\to {\Sigma }^{+}{K}^{-}{\pi }^{+}$ to be $0.16\pm 0.06\pm 0.01$. We also set 90% confidence level upper limits for ${\Xi }_c^{+}\to {\Sigma }^{+}\varphi$ and ${\Xi }_c^{+}\to {\Xi }^{\ast }(1690{)}^0({\Sigma }^{+}{K}^{-})K^{+}$ relative to ${\Xi }_c^{+}\to {\Sigma }^{+}{K}^{-}{\pi }^{+}$ to be 0.12 and 0.05, respectively. We find an indication of the decays ${\Xi }_c^{+}\to {\Omega }^{-}{K}^{+}{\pi }^{+}$ and ${\Xi }_c^{+}\to {\Sigma }^{\ast }(1385{)}^{+}{\bar{K}}^0$ and set 90% confidence level upper limits for the branching ratios with respect to ${\Xi }_c^{+}\to {\Xi }^{-}{\pi }^{+}{\pi }^{+}$ to be 0.12 and 1.72, respectively. Finally, we determine the 90% C.L. upper limit for the resonant contribution ${\Xi }_c^{+}\to {\Xi }^{\ast }(1530{)}^0{\pi }^{+}$ relative to ${\Xi }_c^{+}\to {\Xi }^{-}{\pi }^{+}{\pi }^{+}$ to be 0.10.

14 pages, 8 figures