The $$P_{cs}(4459)$$ pentaquark from a combined effective field theory and phenomenological perspective

The observation of the $P_{cs}(4459)$ by LHCb collaboration adds a new member to set known hidden-charm pentaquarks, which includes $P_c(4312)$, $P_c(4440)$ and $P_c(4457)$. is expected have light-quark content $\Lambda$ baryon ($I=0$, $S=-1$), but its spin unknown. Its closeness $\bar{D}^* \Xi_c$ threshold -- $4478\,{\rm MeV}$ in isospin-symmetric limit suggests molecular hypothesis as plausible explanation for $P_{cs}(4459)$. While absence coupled-channel dynamics heavy-quark symmetry predicts two spin-states be degenerate, power counting arguments indicate that coupling with nearby $\bar{D} \Xi_c'$ \Xi_c^*$ channels might leading order effect. This generates hyperfine splitting $J=\tfrac{3}{2}$ pentaquark will lighter than $J=\tfrac{1}{2}$ configuration, we estimate $5-15\,{\rm MeV}$. We also point out an accidental between $P_c(4440/4457)$ potentials. Finally, argue spectroscopy $J/\psi \Lambda$ decays suggest marginal preference $J = \tfrac{3}{2}$ over \tfrac{1}{2}$.