Study $\Xi_c^+ \to \Lambda {\bar{K}}^0 \pi^+$ and search for the low-lying baryons $\Xi(1/2^-)$ and $\Sigma(1/2^-)$

TL;DR

This paper predicts that the decay process $\\Xi_c^+ o \\Lambda \\bar{K}^0 \\pi^+$ can reveal low-lying baryon resonances \(\Xi(1/2^-)\) and \(\Sigma(1/2^-)\) through invariant mass distributions, guiding experimental searches.

Contribution

The study uses the chiral unitary approach to predict signals of low-lying baryons in a specific decay process, proposing it as an ideal experimental search channel.

Findings

Predicted clear signals of \(\Xi(1/2^-)\) and \(\Sigma(1/2^-)\) in invariant mass distributions.

Identified the decay process as optimal for experimental searches of these baryons.

Provided guidance for experiments like Belle II, LHCb, and STCF.

Abstract

Since searches for the low-lying excited baryons $\Xi(1/2^-)$ and $\Sigma(1/2^-)$ are crucial to deepening our understanding of the light baryon spectrum, we have investigated the Cabibbo-favored process $\Xi_c^+ \to \Lambda {\bar{K}}^0 \pi^+$ by taking into account the $S$-wave pseudoscalar meson-octet baryon interactions within the chiral unitary approach, which could dynamically generate the resonances $\Xi(1/2^-)$ and $\Sigma(1/2^-)$. The contributions from the excited kaons are double Cabibbo-suppressed, and the contribution from the $\Sigma(1385)$ is also suppressed due to Korner-Pati-Woo theory, thus those states are expected to play negligible contributions in this process. We have predicted the $\bar{K}^0 \Lambda$ and $\pi^+\Lambda$ invariant mass distributions, which have the clear signals of the $\Xi(1/2^-)$ and $\Sigma(1/2^-)$. Thus, the $\Xi_c^+ \to \Lambda {\bar{K}}^0 \pi^+$ is an ideal process to search for the low-lying baryons $\Xi(1/2^-)$ and $\Sigma(1/2^-)$, and we make a call for a precise measurements of this process in experiments, such as Belle II, LHCb, and the proposed Super Tau-Charm Facility (STCF).