Measurements of the cross sections for $e^{+}{e}^{-}\to \mathrm{hadrons}$ at 3.650, 3.6648, 3.773 GeV and the branching fraction for $\psi (3770)\to \mathrm{non}-D\bar{D}$

Abstract

Using the BES-II detector at the BEPC Collider, we measured the lowest order cross sections and the $R$ values ($R={\sigma }_{e^{+}{e}^{-}\to \mathrm{hadrons}}^0/{\sigma }_{e^{+}{e}^{-}\to {\mu }^{+}{\mu }^{-}}^0$) for inclusive hadronic event production at the center-of-mass energies of 3.650 GeV, 3.6648 GeV and 3.773 GeV. The results lead to ${\bar{R}}_{uds}=2.224\pm 0.019\pm 0.089$ which is the average of these measured at 3.650 GeV and 3.6648 GeV, and $R=3.793\pm 0.037\pm 0.190$ at $\sqrt{s}=3.773$ GeV. We determined the lowest order cross section for $\psi (3770)$ production to be ${\sigma }_{\psi (3770)}^{\mathrm{B}}=(9.575\pm 0.256\pm 0.813)\mathrm{nb}$ at 3.773 GeV, the branching fractions for $\psi (3770)$ decays to be $BF(\psi (3770)\to D^0{\bar{D}}^0)=(48.9\pm 1.2\pm 3.8)$, $BF(\psi (3770)\to D^{+}{D}^{-})=(35.0\pm 1.1\pm 3.3)$ and $BF(\psi (3770)\to D\bar{D})=(83.9\pm 1.6\pm 5.7)$, which result in the total non-$D\bar{D}$ branching fraction of $\psi (3770)$ decay to be $BF(\psi (3770)\to \mathrm{non}-D\bar{D})=(16.1\pm 1.6\pm 5.7)$.

11 pages, 5 figures

Cited by in corpus (14)

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• Measurements of the braching fractions for psi(3770)--> D0D0-bar,D+D-,DD-bar$ and the resonance parameters of psi(3770) and psi(2S)
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• Hadron Spectroscopy: Theory and Experiment
• QCD prediction for the non-$D\bar{D}$ annihilation decay of $\psi (3770)$
• Precison Measurements of the Mass, the Widths of $\psi (3770)$ Resonance and the Cross Section $\sigma [e^{+}{e}^{-}\to \psi (3770)]$ at $E_{\mathrm{cm}}=3.7724$ GeV
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