Hidden-Charm Pentaquarks with Strangeness in a Chiral Quark Model

• Published in: Symmetry (Basel) 2024-03, Vol.16 (3), p.354
• Main Authors: Yang, Gang, Ping, Jialun, Segovia, Jorge
• Format: Article
• Language: English
• Subjects: Charm (particle physics); Collaboration; Hadrons; quantum chromodynamics; Quantum numbers; Quark models; Quarks; Strangeness; Symmetry
• ISSN: 2073-8994; 2073-8994
• DOI: 10.3390/sym16030354

The LHCb collaboration has recently announced the discovery of two hidden-charm pentaquark states with strange quark content, Pcs(4338) and Pcs(4459); its analysis points towards having both hadrons’ isospins equal to zero and spin-parity quantum numbers 12− and 32−, respectively. Herein, we perform a systematical investigation of the qqscc¯(q=u,d) system by means of a chiral quark model, along with a highly accurate computational method, the Gaussian expansion approach combined with the complex scaling technique. baryon-meson configurations in both singlet- and hidden-color channels are considered. The Pcs(4338) and Pcs(4459) signals can be well identified as molecular bound states with dominant components ΛJ/ψ(60%) and ΞcD(23%) for the lowest-energy case and ΞcD∗(72%) for the highest-energy one. In addition, it seems that some narrow resonances can also be found in each allowed I(JP) channel in the energy region of 4.6–5.5 GeV, except for the 1(12−) channel where a shallow bound state with dominant Ξc∗D∗ structure is obtained at 4673 MeV with binding energy EB=−3 MeV. These exotic states are expected to be confirmed in future high-energy experiments.