Investigation of the strange pentaquark candidate $P_{\psi s}^{\mathrm{\Lambda }}(4338){}^0$ recently observed by LHCb

The recently observed strange pentaquark candidate, $P_{\psi s}^{\mathrm{\Lambda }}(4338){}^0$, is investigated to provide information about its nature and substructure. To this end, its mass and width through the decay channels $P_{\psi s}^{\mathrm{\Lambda }}(4338){}^0\to J\mathrm{/}\psi \mathrm{\Lambda }$ and $P_{\psi s}^{\mathrm{\Lambda }}(4338){}^0\to {\eta }_c\mathrm{\Lambda }$ are calculated by applying two- and three-point QCD sum rules, respectively. The state is considered as a ${\mathrm{\Xi }}_c\bar{D}$ meson-baryon molecular structure with spin-parity quantum numbers $J^P={\frac{1}{2}}^{-}$. The obtained mass, $m_{P_{\psi s}^{\mathrm{\Lambda }}(4338){}^0}=4338\pm 130\mathrm{M}\mathrm{e}\mathrm{V}$, and width, ${\mathrm{\Gamma }}_{P_{\psi s}^{\mathrm{\Lambda }}(4338){}^0}=10.40\pm 1.93\mathrm{M}\mathrm{e}\mathrm{V}$, are consistent with the experimental data within the presented uncertainties. This allows us to assign a ${\mathrm{\Xi }}_c\bar{D}$ molecular structure of $J^P={\frac{1}{2}}^{-}$ for the $P_{\psi s}^{\mathrm{\Lambda }}(4338){}^0$ state.