Observation of $\psi(3686) \to K^{-}\Lambda(1520)\bar{\Xi}^{+} + c.c.$

TL;DR

This paper reports the first observation of a specific decay mode of the $oldsymbol{\psi(3686)}$ particle, measuring its branching fraction with high statistical significance using a large data sample from BESIII.

Contribution

It provides the first experimental evidence of the decay $oldsymbol{\psi(3686) o K^{-}\Lambda(1520)ar{\Xi}^{+}}$ and measures its product branching fraction.

Findings

First observation of the decay mode.

Measured product branching fraction: $(9.5 \pm ext{0.8} ext{(stat)} ext{±} ext{1.1} ext{(syst)}) imes 10^{-7}$.

Large data sample of $2712.4 imes 10^6$ $oldsymbol{\psi(3686)}$ events used.

Abstract

Based on $(2712.4 \pm 14.3)\times 10^6$ $\psi(3686)$ events collected at the BESIII detector operating at the BEPCII collider, we present the first observation of the decay $\psi(3686) \to K^{-}\Lambda(1520)\bar{\Xi}^{+} + c.c.$. The product branching fraction ${\cal B}[\psi(3686) \to K^{-}\Lambda(1520)\bar{\Xi}^{+} + c.c.] \times {\cal B}[\Lambda(1520) \to pK^{-}]$ is measured to be $(9.5 \pm 0.8 \pm 1.1) \times 10^{-7}$, where the first uncertainty is statistical and the second systematic.