Strong $Z_c^{+}(3900)\to J/\psi {\pi }^{+};{\eta }_c{\rho }^{+}$ decays in QCD

Abstract

The widths of the strong decays $Z_c^{+}(3900)\to J/\psi {\pi }^{+}$ and $Z_c^{+}(3900)\to {\eta }_c{\rho }^{+}$ are calculated. To this end, the mass and decay constant of the exotic $Z_c^{+}(3900)$ state are computed by means of a two-point sum rule. The obtained results are then used to calculate the strong couplings $g_{Z_{c}J/\psi \pi }$ and $g_{Z_c{\eta }_c\rho }$ employing QCD sum rules on the light-cone supplied by a technique of the soft-meson approximation. We compare our predictions on the mass and decay widths with available experimental data and other theoretical results.

Comments: 11 Pages, 3 Figures and 2 Tables; To be published by Physical Review D