Toward charged $Z_{cs}(3985)$ structure under a reflection mechanism

Abstract

Very recently, the BESIII collaboration reported a charged hidden-charm structure with strangeness in the recoil mass of $K^{+}$ of a process $e^{+}{e}^{-}\to D_s^{\ast -}{D}^0{K}^{+}$ or $D_s^{-}{D}^{\ast 0}{K}^{+}$, which is named as $Z_{cs}(3985{)}^{-}$. The newly observed charged structure can be treated as a partner structure with strangeness of well-known $Z_c(3885{)}^{-}$ reported in a process $e^{+}{e}^{-}\to D^{\ast -}{D}^0{\pi }^{+}$. In this work, we propose a novel picture to understand the nature of $Z_{cs}(3985)$. By performing a combined analysis for the line shape of the recoil mass distribution of $K^{+}$ at five energy points $\sqrt{s}=4.628,4.641,4.661,4.681,4.698$ GeV, we find that the $Z_{cs}(3985)$ can be explained as a reflection structure of charmed-strange meson $D_{s2}^{\ast }(2573)$, which is produced from the open-charm decay of $Y(4660)$ with a $D_s^{\ast }$ meson. Furthermore, we predicted the angular distribution of final state $D_s^{\ast -}$ in process $e^{+}{e}^{-}\to D_s^{\ast -}{D}^0{K}^{+}$ based on our proposed reaction mechanism, which may be an essential criterion to test the non-resonant nature of $Z_{cs}(3985)$ further.

Comments: 5 pages, 1 table and 3 figures