Some decay properties of hidden-charm pentaquarks as baryon-meson molecules

It is pointed out that the previously suggested interpretation of the hidden-charm pentaquarks $P_c(4312)$, $P_c(4440)$, and $P_c(4457)$ as molecular bound states of ${\mathrm{\Sigma }}_c\overline{D}$ and ${\mathrm{\Sigma }}_c{\overline{D}}^{*}$ baryon-meson pairs gives rise to specific relations for their decays. In particular, the heavy-quark spin symmetry predicts ratios of rates of decays of each of the molecules to $J/\psi p$ and to ${\eta }_{c}p$ as well as of the decays to ${\mathrm{\Lambda }}_c\overline{D}$ and to ${\mathrm{\Lambda }}_c{\overline{D}}^{*}$. Experimental studies of these relations would thus provide an indicative probe of the molecular structure.

Figure 1

The scattering ${\mathrm{\Sigma }}_c{\overline{D}}^{(*)}\to {\mathrm{\Lambda }}_c{\overline{D}}^{(*)}$ due to one pion exchange.