Measurement of the branching fractions of the Cabibbo-favored decays $\Lambda_{c}^{+}\to\Lambda K_{S}^{0}K^{+}$ and $\Lambda_{c}^{+}\to\Xi^{0}K_{S}^{0}\pi^{+}$ and search for $\Lambda_{c}^{+}\to\Sigma^{0} K_{S}^{0}K^{+}$

TL;DR

This paper reports precise measurements of branching fractions for specific Cabibbo-favored decays of the $\Lambda_c^+ ext{} ext{baryon}$, including the first observation of $\Lambda_c^+ o\Xi^0 K_S^0 \pi^+$, using data from BESIII.

Contribution

It provides the first measurement of the $\\Lambda_c^+ o \\Xi^0 K_S^0 \\pi^+$ decay and refines branching fractions for $\\Lambda_c^+ o \\Lambda K_S^0 K^+$, offering new data to test theoretical models.

Findings

First observation of $\\Lambda_c^+ o \\Xi^0 K_S^0 \\pi^+$ with $6.6\sigma$ significance.

Measured branching fraction of $\\Lambda_c^+ o \\Lambda K_S^0 K^+$ consistent with previous results.

Set upper limit on $\\Lambda_c^+ o \\Sigma^0 K_S^0 K^+$ branching fraction.

Abstract

Based on $e^{+}e^{-}$ collision data corresponding to an integrated luminosity of about 4.5 fb$^{-1}$ collected at center-of-mass energies between 4599.53 MeV and 4698.82 MeV with the BESIII detector, the absolute branching fraction of the Cabibbo-favored decay $\Lambda_{c}^{+}\to\Lambda K_{S}^{0}K^{+}$ is measured to be $(3.12\pm0.46\pm0.15)\times10^{-3}$. Combined with a previous measurement from the BESIII Collaboration, the branching fraction of the decay $\Lambda_{c}^{+}\to\Lambda K_{S}^{0}K^{+}$ is calculated to be $(3.07\pm0.26\pm0.13)\times10^{-3}$. The decay $\Lambda_{c}^{+}\to\Xi^{0}K_{S}^{0}\pi^{+}$ is observed for the first time with a statistical significance of $6.6\sigma$, and its branching fraction is determined to be $(3.70\pm0.60\pm0.21)\times10^{-3}$. In addition, a search for the decay $\Lambda_{c}^{+}\to\Sigma^{0} K_{S}^{0}K^{+}$ is performed and its branching fraction is determined to be $(0.80^{+0.28}_{-0.24}\pm0.16)\times10^{-3}$, corresponding to an upper limit of $1.28\times10^{-3}$ at $90\%$ confidence level. These measurements provide new information that can be used to distinguish between theoretical models.