Production mechanism of hidden-charm pentaquark states $P_{c\bar{c}s}$ with strangeness $S=-1$

Abstract

We investigate the hidden-charm pentaquark states with strangeness $S=-1$ ($P_{c\bar{c}s}$) within an off-shell coupled-channel approach based on effective Lagrangians that respect heavy-quark spin symmetry, SU(3) flavor symmetry, and hidden local symmetry. All relevant meson-baryon two-body channels composed of low-lying anti-charmed mesons and singly-charmed baryons with $S=-1$, as well as the $J/\psi \Lambda$ channel, are included. We find a total of eleven negative-parity states and three positive-parity states. Among the negative-parity states, the $P_{c\bar{c}s}(4338)$ and $P_{c\bar{c}s}(4459)$ can possibly be interpreted as $\bar{D}{\Xi }_c$ and ${\bar{D}}^{\ast }{\Xi }_c$ molecular states, respectively. We identify a second state, $P_{c\bar{c}s}(4472)$, located close to the $P_{c\bar{c}s}(4459)$ but with different spin and width, which may correspond to the structure observed by the Belle Collaboration. Both states are generated from the ${\bar{D}}^{\ast }{\Xi }_c$ channel and can be interpreted as spin partners. Their properties are consistent with recent experimental observations, providing strong support for the molecular interpretation of the $P_{c\bar{c}s}$ states. We also observe a two-pole structure near the ${\bar{D}}_s^{\ast }{\Lambda }_c$ and $\bar{D}{\Xi }_c^{{}^{\prime }}$ thresholds, and find virtual and resonance states in the ${\bar{D}}^{\ast }{\Xi }_c^{{}^{\prime }}$ channel depending on spin-parity.

Comments: 19 pages and 8 figures. The title was changed and a few paragraphs were added. The final version for publication in Physical Review D