Double-strangeness hidden-charm pentaquarks

TL;DR

This paper predicts the existence of double-strangeness hidden-charm pentaquark states using a coupled-channel approach, identifying five negative-parity and three positive-parity states with specific spins and energies, guiding future experimental searches.

Contribution

It introduces a novel theoretical framework to predict double-strangeness hidden-charm pentaquarks, including their masses, spins, parities, and decay channels, expanding the understanding of exotic hadrons.

Findings

Five negative-parity $P_{car{c}ss}$ states below thresholds.

Three positive-parity states with substantial widths.

Predictions for experimental detection in the $J/ar{J} ightarrow ext{channels}$.

Abstract

We investigate the possible existence of double-strangeness hidden-charm pentaquark states, denoted as $P_{c\bar{c}ss}$, within an off-shell coupled-channel formalism. Eleven meson-baryon channels with total strangeness $S = -2$ are constructed by combining charmed mesons and singly charmed baryons. The two-body scattering amplitudes are derived from an effective Lagrangian that respects heavy-quark spin symmetry, hidden local symmetry, and flavor SU(3) symmetry. The Bethe-Salpeter equation is solved using the Blankenbecler-Sugar reduction scheme, and resonances are identified as poles in the scattering amplitudes on the complex energy plane. We find five negative-parity $P_{c\bar{c}ss}$ states with spins $J = 1/2$, $3/2$, and $5/2$, all located below their relevant thresholds. Three positive-parity states are also found: two with $J = 1/2$ and one with $J = 3/2$, lying above the thresholds with substantial widths. The coupling strengths of each resonance to relevant meson-baryon channels are extracted. The sensitivity of the results to the cutoff parameter $\Lambda_0 = \Lambda - m$ is examined. These results provide theoretical predictions that may assist future experimental searches for $P_{c\bar{c}ss}$ states in the $J/\psi\,\Xi$ channel.