Kaon-induced production of strange hidden-charm molecular pentaquarks $P^\Lambda_{\psi s}$ from proton

TL;DR

This paper investigates the production of strange hidden-charm pentaquarks via kaon interactions, predicting molecular states and cross section features to guide future experimental searches.

Contribution

It introduces a coupled-channel approach with effective Lagrangians and the Bethe-Salpeter equation to predict molecular pentaquark states and their production cross sections.

Findings

Predicted a structure near the $ ext{Xi}_car{D}$ threshold for $P^ extLambda_{ extpsi s}(4338)$.

Identified peaks in cross sections associated with $P^ extLambda_{ extpsi s}(4459)$ near the $ ext{Xi}_car{D}^*$ threshold.

No clear pentaquark signals in higher energy $ extLambda_car{D}_s^{(*)}$ channels, only threshold cusps.

Abstract

In this work, we investigate the kaon-induced production of strange hidden-charm pentaquark $P^\Lambda_{\psi s}$ states, including the $P^\Lambda_{\psi s}(4459)$ and $P^\Lambda_{\psi s}(4338)$ observed by the LHCb collaboration. Coupled-channel interactions involving the channels $\bar{K}N$, $\Xi_c^{(*)}\bar{D}^{(*)}$, $\Xi'_c\bar{D}^{(*)}$, $\Lambda_c\bar{D}_s^{(*)}$, and $\Lambda J/\psi$ are studied using effective Lagrangians to describe these interactions. The potential kernels are constructed within the one-boson-exchange model and implemented into the quasipotential Bethe-Salpeter equation to calculate the scattering amplitudes. From these amplitudes, the partial-wave cross sections for kaon-induced production are predicted alongside the poles corresponding to strange hidden-charm molecular pentaquarks. The analysis reveals complex structures in the cross sections due to molecular states. A structure near the $\Xi_c\bar{D}$ threshold is predicted in the $\Lambda_c\bar{D}_s$ channel, corresponding to $P^\Lambda_{\psi s}(4338)$. Both molecular states near the $\Xi_c\bar{D}^*$ threshold with $J^P = 1/2^-$ and $J^P = 3/2^-$, associated with $P^\Lambda_{\psi s}(4459)$, produce peaks in the $\Xi'_c\bar{D}$ channel, which vary significantly with the cutoff. Additionally, a molecular state with $J^P = 3/2^-$ near the $\Xi_c^*\bar{D}$ threshold gives rise to a peak in the $\Xi_c\bar{D}^*$ channel. In the higher energy region, from 4350 to 4550 MeV, although the cross sections in the $\Lambda_c\bar{D}_s^{(*)}$ channels are substantial, no distinct structures corresponding to strange hidden-charm pentaquarks are identified, apart from some threshold-related cusps. These results provide valuable theoretical insights and serve as a foundation for future experimental studies of strange hidden-charm pentaquarks using kaon beams at J-PARC and JLab.