Effects of $N(2080){3/2}^{-}$ and $N(2270)3/2^{-}$ molecules on $K^{\ast }\Sigma$ photoproduction

Abstract

In the present work, we re-analyze the available data for $\gamma p\to K^{\ast +}{\Sigma }^0$ and $\gamma p\to K^{\ast 0}{\Sigma }^{+}$ by considering the contributions from the $N(2080){3/2}^{-}$ and $N(2270)3/2^{-}$ molecules instead of any nucleon resonances in the $s$ channel, where the $N(2080)3/2^{-}$ was proposed to be a $K^{\ast }\Sigma$ molecule as the strange partner of the $P_c^{+}(4457)$ hadronic molecular state, and the $N(2270)3/2^{-}$ was assumed to be a $K^{\ast }{\Sigma }^{\ast }$ molecule as the strange partner of the ${\bar{D}}^{\ast }{\Sigma }_c^{\ast }$ bound states that are predicated as members in the same heavy-quark spin symmetry multiplet as the $P_c$ states. It turns out that all the available cross-section data can be well reproduced, indicating that the molecular structures of the possible $N(2080){3/2}^{-}$ and $N(2270)3/2^{-}$ states are compatible with the available data for $K^{\ast }\Sigma$ photoproduction reactions. Further analysis shows that for both $\gamma p\to K^{\ast +}{\Sigma }^0$ and $\gamma p\to K^{\ast 0}{\Sigma }^{+}$ reactions, the $N(2080){3/2}^{-}$ exchange provides dominant contributions to the cross-sections in the near-threshold energy region, and significant contributions from the $N(2270)3/2^{-}$ exchange to the cross-sections in the higher energy region are also found. Predictions of the beam asymmetry $\Sigma$, target asymmetry $T$, and recoil baryon asymmetry $P$ are presented and compared with those from our previous work. Measurements of the data on these observables are called on to further constrain the reaction mechanisms of $K^{\ast }\Sigma$ photoproduction reactions and to verify the molecular scenario of the $N(2080){3/2}^{-}$ and $N(2270)3/2^{-}$ states.

Comments: 10 pages, 8 figures