First observation of the decay $\chi_{cJ}\to \Sigma^{+}\bar{p}K_{S}^{0}+c.c. ~(J = 0, 1, 2)$

TL;DR

This paper reports the first observation of specific decay modes of the $oldsymbol{ ext{chi}_{cJ}}$ charmonium states into $oldsymbol{ ext{Sigma}^+ ar{p} K_S^0}$ final states, measuring their branching fractions with data from BESIII.

Contribution

The study provides the first measurements of branching fractions for $ ext{chi}_{cJ}$ decays into $ ext{Sigma}^+ ar{p} K_S^0$, expanding knowledge of charmonium decay channels.

Findings

Measured branching fractions for $ ext{chi}_{c0,1,2}$ decays.

No intermediate resonances observed in these decay processes.

First observation of these decay modes.

Abstract

Using E1 radiative transitions $\psi(3686) \to \gamma\chi_{cJ}$ from a sample of $(448.1 \pm 2.9)\times10^{6}$ $\psi(3686)$ events collected with the BESIII detector, the decays $\chi_{cJ}\to \Sigma^{+}\bar{p}K_{S}^{0}+c.c.~(J = 0, 1, 2)$ are studied. The decay branching fractions are measured to be $\mathcal{B}(\chi_{c0}\to \Sigma^{+}\bar{p}K_{S}^{0}+c.c.) = (3.52 \pm 0.19\pm 0.21)\times10^{-4}$, $\mathcal{B}(\chi_{c1}\to \Sigma^{+}\bar{p}K_{S}^{0}+c.c.) = (1.53 \pm 0.10\pm 0.08)\times10^{-4}$, and $\mathcal{B}(\chi_{c2}\to \Sigma^{+}\bar{p}K_{S}^{0}+c.c.) = (8.25 \pm 0.83 \pm 0.49)\times10^{-5}$, where the first and second uncertainties are the statistical and systematic ones, respectively. No evident intermediate resonances are observed in the studied processes.