Production and decay of anticharmed pentaquark state with quark content $\bar{c}sudd$

Abstract

We used an effective Lagrangian approach to investigate the production of the anticharmed pentaquark state $P_{\bar{c}s}^{(\ast )-}$ with the minimal quark content $\bar{c}sudd$ in the ${\Lambda }_b^0$ decay and its decay into the $\Lambda D^{(\ast )-}$ and $\Sigma D^{(\ast )-}$. In our calculation, the $P_{\bar{c}s}^{(\ast )-}$ is considered as the molecule state of the $n{D}_{s0(s1)}^{-}$ in an $S$ wave, and its production and decay occur via triangle loops at the hadron level. The predicted branching fractions for the processes ${\Lambda }_b^0\to P_{\bar{c}s}^{(\ast )-}{D}^{+}$ are around $10^{-4}\sim 10^{-3}$. The partial decay widths of the $P_{\bar{c}s}^{(\ast )-}\to \Lambda D^{(\ast )-}$ are between $0.1$ and $\sim 10\mathrm{MeV}$, whereas the decay widths of the $P_{\bar{c}s}^{(\ast )-}\to \Sigma D^{(\ast )-}$ are about one order of magnitude smaller. It is found that the width ratios for the $P_{\bar{c}s}^{(\ast )-}$ decays are nearly independent of the model parameter $\alpha$. It is hoped that these predictions could be helpful in searching for the anticharmed-strange pentaquark candidates in future LHCb experiments.

Comments: 11 pages, 6 figures, 3 tables, major changes for the coupling constants for the resonances and related results/description change, accepted by EPJC