Nature of LHCb pentaquark candidates

Determine the underlying nature of the LHCb-reported pentaquark candidates, specifically the charged Pc states observed in Λb → J/ψ p K− decays and the strange Pcs(4459) and Pcs(4338) states observed in Ξb− → J/ψ Λ K− and B− → J/ψ Λ p̄ decays, by establishing whether they are tightly bound pentaquark states, loosely bound baryon–meson molecular states, or artifacts of rescattering effects.

Background

The paper summarizes several pentaquark candidates reported by LHCb: charged Pc states near Σc+ D(*)0 thresholds, the strange Pcs(4459) near Ξc0 D*0 threshold, and Pcs(4338) near Ξc+ D− threshold. Multiple theoretical interpretations exist, including tightly bound pentaquark configurations, hadronic molecules, and rescattering phenomena.

Despite these discoveries, the authors emphasize that the intrinsic nature of these states is not established. Their investigation uses Belle data to search for related structures in Υ(1S,2S) inclusive decays and to measure inclusive J/ψ production, providing complementary information but not resolving the fundamental classification of the states.