Measurement of Total Hadronic Cross Section in Electron-Positron Annihilation in the Upsilon Region.
The total cross section of the reaction e('+)e(' -) (--->) hadrons was measured in the region of the upsilon resonances at the Cornell Electron Storage Ring. Measurements of the resonance parameters are presented. The region is searched for additional resonances with a null result; upper limits are presented on the sizes of possible additional resonances. A measurement of R = (sigma)(e('+)e('-) ( --->) hadrons)/. (e('+)e('-) (--->) (mu)('+)(mu)('-)) is presented: R = 3.63 (+OR-) 0.06 (+OR-) 0.37. A step in R across the flavor threshold is observed. *Research supported by the National Science Foundation.
- Pub Date:
- Physics: Elementary Particles and High Energy