$P_{cs}(4459)$ and other possible molecular states from $Xi_{c}^{(*)}bar{D}^{(*)}$ and $Xi_cbar{D}^{(*)}$ interactions


الملخص بالإنكليزية

Recently, the LHCb Collaboration reported a new structure $P_{cs}(4459)$ with a mass of 19 MeV below the $Xi_c bar{D}^{*} $ threshold. It may be a candidate of molecular state from the $Xi_c bar{D}^{*} $ interaction. In the current work, we perform a coupled-channel study of the $Xi_c^*bar{D}^*$, $Xi_cbar{D}^*$, $Xi^*_cbar{D}$, $Xi_cbar{D}^*$, $Xi_cbar{D}$, and $Xi_cbar{D}$ interactions in the quasipotential Bethe-Salpeter equation approach. With the help of the heavy quark chiral effective Lagrangian, the potential is constructed by light meson exchanges. Two $Xi_c bar{D}^{*} $ molecular states are produced with spin parities $ J^P=1/2^-$ and $3/2^- $. The lower state with $3/2^-$ can be related to the observed $P_{cs}(4450)$ while two-peak structure can not be excluded. Within the same model, other strange hidden-charm pentaquarks are also predicted. Two states with spin parities $1/2^-$ and $3/2^-$ are predicted near the $Xi_cbar{D}$, $Xi_cbar{D}$, and $Xi_c^*bar{D}$ thresholds, respectively. As two states near $Xi_c bar{D}^{*}$ threshold, two states are produced with $1/2^-$ and $3/2^-$ near the $Xi_cbar{D}^*$ threshold. The couplings of the molecular states to the considered channels are also discussed. The experimental research of those states are helpful to understand the origin and internal structure of the $P_{cs}$ and $P_c$ states.

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