Studies of charmed strange baryons in the $\Lambda D$ final state at Belle

TL;DR

This paper reports the discovery and detailed analysis of new charmed strange baryons in the $\Lambda D$ final state, providing measurements of their properties and decay modes using Belle data.

Contribution

It presents the first observation of $\Xi_{c}(3055)^{0}$ decay into $\Lambda D^{0}$ and evidence for $\Xi_c(3055)^{+}$ and $\Xi_c(3080)^{+}$ decays into $\Lambda D^{+}$, with improved measurements of their branching ratios, masses, and widths.

Findings

Discovery of $\\Xi_{c}(3055)^{0}$ in $\\Lambda D^{0}$ decay.

First evidence of $\\Xi_c(3055)^{+}$ and $\\Xi_c(3080)^{+}$ decays into $\\Lambda D^{+}$.

Measured ratios of branching fractions with improved precision.

Abstract

We report the discovery of $\Xi_{c}(3055)^{0}$, observed by its decay into the final state $\Lambda D^{0}$, and present the first observation and evidence of the decays of $\Xi_c(3055)^{+}$ and $\Xi_c(3080)^{+}$ into $\Lambda D^{+}$. We also perform a combined analysis of the $\Lambda D^{+}$ with the $\Sigma_{c}^{++}K^{-}$ and $\Sigma_{c}^{\ast ++}K^{-}$ decay modes to measure the ratios of branching fractions, masses and widths with improved accuracy. We measure the ratios of branching fractions ${\cal B}(\Xi_{c}(3055)^{+} \to \Lambda D^{+})/{\cal B}(\Xi_{c}(3055)^{+} \to \Sigma_{c}^{++}K^{-})=5.09\pm1.01\pm0.76$, ${\cal B}(\Xi_{c}(3080)^{+} \to \Lambda D^{+})/{\cal B}(\Xi_{c}(3080)^{+} \to \Sigma_{c}^{++}K^{-})=1.29\pm0.30\pm0.15$, and ${\cal B}(\Xi_{c}(3080)^{+} \to \Sigma_{c}^{\ast ++}K^{-})/{\cal B}(\Xi_{c}(3080)^{+} \to \Sigma_{c}^{++}K^{-})=1.07\pm0.27\pm0.01$, where the uncertainties are statistical and systematic. The analysis is performed using a 980 fb$^{-1}$ data sample collected with the Belle detector at the KEKB asymmetric-energy $e^{+}e^{-}$ collider.