Analysis of BaBar, Belle, BES-II, CLEO and KEDR data on $\psi (3770)$ line shape and determination of the resonance parameters

Abstract

The available data on the $D\overline{D}$ and inclusive hadronic cross sections in the $\psi (3770)$ region from the BaBar, Belle, BES-II, CLEO and KEDR experiments have been analyzed assuming that systematic uncertainties on cross sections measured by different detectors are not correlated. Four theoretical models predicting the $\psi (3770)$ line shape were considered for the $D\overline{D}$ channel. All of them gave satisfactory description of the data. The combined analysis of the $D\overline{D}$ and inclusive hadronic channel was performed using the model based on the vector dominance approach and accounting for the contribution of the $\psi (2S)$ tail to the $D\overline{D}$ cross section. The following values of the mass, total width, electron width and decay probability to the non-$D\overline{D}$ states were obtained: $M=3779.8\pm 0.6\text{MeV},\Gamma =25.8\pm 1.3\text{MeV},{\Gamma }_{ee}=196\pm 18\text{eV},{\mathcal{B}}_{nD\overline{D}}=0.164\pm 0.049$, where the errors quoted include both statistical and dominant systematic uncertainties.