The $Z_{cs}(3985)$ as a threshold effect from the ${\bar{D}}_s^{\ast }D+{\bar{D}}_s{D}^{\ast }$ interaction

Abstract

We study the $e^{+}{e}^{-}\to K^{+}(D_s^{\ast -}{D}^0+D_s^{-}{D}^{\ast 0})$ reaction recently measured at BESIII, from where a new $Z_{cs}$ state has been reported. We study the interaction of ${\bar{D}}_s{D}^{\ast }$ with the coupled channels $J/\psi K^{-}$, $K^{\ast -}{\eta }_c$, $D_s^{-}{D}^{\ast 0}$, $D_s^{\ast -}{D}^0$ by means of an extension to the charm sector of the local hidden gauge approach. We find that the $D_s^{-}{D}^{\ast 0}+D_s^{\ast -}{D}^0$ combination couples to $J/\psi K^{-}$ and $K^{\ast -}{\eta }_c$, but the $D_s^{-}{D}^{\ast 0}-D_s^{\ast -}{D}^0$ combination does not. The coupled channels help to build up strength in the $D_s^{-}{D}^{\ast 0}+D_s^{\ast -}{D}^0$ diagonal scattering matrix close to threshold and, although the interaction is not strong enough to produce a bound state or resonance, it is sufficient to produce a large accumulation of strength at the ${\bar{D}}_s{D}^{\ast }$ threshold in the $e^{+}{e}^{-}\to K^{+}(D_s^{\ast -}{D}^0+D_s^{-}{D}^{\ast 0})$ reaction in agreement with experiment.

7 pages, 2 figures: The title is changed

References in corpus (7)

• Axial Resonances in the Open and Hidden Charm Sectors
• Hidden gauge formalism for the radiative decays of axial-vector mesons
• $Z_b$ and $Z_c$ Exotic States as Coupled Channel Cusps
• Could the near-threshold $XYZ$ states be simply kinematic effects?
• Study of the $Z_c^{+}$ channel using lattice QCD
• Clues for the existence of two $K_1(1270)$ resonances
• Treating $Z_c(3900)$ and $Z(4430)$ as the ground-state and first radially excited tetraquarks

Cited by in corpus (6)

• Emergence of molecular-type characteristic spectrum of hidden-charm pentaquark with strangeness embodied in the $P_{\psi s}^{\Lambda }(4338)$ and $P_{cs}(4459)$
• A combined analysis of the $Z_c(3900)$ and the $Z_{cs}(3985)$ exotic states
• A unified description of the hidden-charm tetraquark states $Z_{cs}(3985)$, $Z_c(3900)$ and $X(4020)$
• Photoproduction of strange hidden-charm and hidden-bottom states
• The possibility of $X(4014)$ as a $D^{\ast }{\bar{D}}^{\ast }$ molecular state
• Spectrum of Hidden-Charm, Open-Strange Exotics in the Dynamical Diquark Model