Looking for a hidden-charm pentaquark state with strangeness $S=-1$ from $\Xi^-_b$ decay into $J/\psi K^- \Lambda$

TL;DR

This paper predicts a new hidden-charm pentaquark with strangeness $S=-1$ in the decay of $\xi_b^-$, based on a molecular interpretation of the $P_c(4450)$, and suggests it can be observed through differential cross section measurements.

Contribution

It introduces a theoretical prediction of a strangeness counterpart to the $P_c(4450)$ pentaquark in $\xi_b^-$ decay, using a molecular approach and decay mechanism modeling.

Findings

Prediction of a detectable strangeness hidden-charm pentaquark state.

Estimated decay rate comparable to observed $\xi_b^0$ decay.

Clear differential cross section signature for experimental search.

Abstract

Assuming that the recently observed hidden-charm pentaquark state, $P_c(4450)$, is of molecular nature as predicted in the unitary approach, we propose to study the decay of $\Xi^-_b\rightarrow J/\psi K^- \Lambda$ to search for the strangeness counterpart of the $P_c(4450)$. There are three ingredients in the decay mechanism: the weak decay mechanism, the hadronization mechanism, and the finite state interactions in the meson-baryon system of strangeness $S=-2$ and isospin $I=1/2$ and of the $J/\psi\Lambda$. All these have been tested extensively. As a result, we provide a genuine prediction of the differential cross section where a strangeness hidden-charm pentaquark state, the counterpart of the $P_c(4450)$, can be clearly seen. The decay rate is estimated to be of similar magnitude as the $\Lambda_b^0\rightarrow J/\psi K^- p$ observed by the LHCb collaboration.