Combined fit to the cross sections of $e^+e^- rightarrow pi Z_c(3900) rightarrow pipi J/psi$ and $e^+e^- rightarrow pi Z_c(3900) rightarrow pi Dbar{D}^{*}$

The cross sections of $e^+e^- rightarrow pi Z_c(3900) rightarrow pipi J/psi$ and $e^+e^- rightarrow pi Z_c(3900) rightarrow pi Dbar{D}^{*}$ have been measured by BESIII experiment. We try to perform a combined fit to the cross sections with one Breit-Wigner function, the fit results show the structures mass and width are $M=(4232pm5)$ MeV/$c^2$, $Gamma=(65pm21)$ MeV. The ratio $frac{mathcal{B}(Z_c(3900)rightarrow Dbar{D}^{*})}{mathcal{B}(Z_c(3900)rightarrowpi J/psi)}$ is determined to be $(16pm6)$. We also try to fit the cross sections with two Breit-Wigner functions, while we cant come to any definitive conclusions about the second structure. More measurements are desired to improve the understanding of $e^+e^- rightarrow pi Z_c(3900)$ line shape.