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

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).

8 pages, 9 figures