Measurement of the Total Cross Section for Hadronic Production by e+e- Annihilation at Energies between 2.6-5 Gev

Abstract

Using the upgraded Beijing Spectrometer (BESII), we have measured the total cross section for $e^{+}{e}^{-}$ annihilation into hadronic final states at center-of-mass energies of 2.6, 3.2, 3.4, 3.55, 4.6 and 5.0 GeV. Values of $R$, $\sigma (e^{+}{e}^{-}\to hadrons)/\sigma (e^{+}{e}^{-}\to {\mu }^{+}{\mu }^{-})$, are determined.

Submitted to Phys. Rev. Lett