Strong decays of the Ξ b ( 6227 ) as a Σ b K ¯ molecule

We study the strong decays of the newly observed ${\mathrm{\ensuremath{\Xi}}}_{b}(6227)$ assuming that it is a pure ${\mathrm{\ensuremath{\Sigma}}}_{b}\overline{K}$ molecular state. Considering four possible spin-parity assingments ${J}^{P}=1/{2}^{\ifmmode\pm\else\textpm\fi{}}$ and $3/{2}^{\ifmmode\pm\else\textpm\fi{}}$, the partial decay widths of the ${\mathrm{\ensuremath{\Sigma}}}_{b}\overline{K}$ molecular state into ${\mathrm{\ensuremath{\Lambda}}}_{b}\overline{K}$, ${\mathrm{\ensuremath{\Xi}}}_{b}\ensuremath{\pi}$, and ${\mathrm{\ensuremath{\Xi}}}_{b}^{\ensuremath{'}}\ensuremath{\pi}$ final states through hadronic loops are evaluated with the help of the effective Lagrangians. In comparison with the LHCb data, the spin-party $1/{2}^{\ensuremath{-}}$ assignment is preferred while those of ${J}^{P}=1/{2}^{+}$ and ${J}^{P}=3/{2}^{\ifmmode\pm\else\textpm\fi{}}$ are disfavored. In addition, we show that the two allowed decay modes ${\mathrm{\ensuremath{\Lambda}}}_{b}\overline{K}$ and ${\mathrm{\ensuremath{\Xi}}}_{b}\ensuremath{\pi}$ of the ${\mathrm{\ensuremath{\Xi}}}_{b}(6227)$, being a $S$-wave ${\mathrm{\ensuremath{\Sigma}}}_{b}\overline{K}$ molecular state, have almost equal branching ratios.