Abstract
We have measured the R value in non-resonant e+e- annihilation using the ARGUS detector at the storage ring DORIS II. At a centre-of-mass energy {Mathematical expression} GeV the ratio of the hadronic cross-section to the μ-pair cross section in lowest order QED has been determined to be R=3.46±0.03±0.13. In addition, we have measured the charged-particle multiplicities in non-resonant hadron production at {Mathematical expression} GeV just below the B {Mathematical expression} threshold and in Υ{hooked} (4 S) resonance decays. For the average charged-particle multiplicities in continuum events and Υ{hooked}(4 S)→B {Mathematical expression} decays we obtain <n>cont=8.35±0.02±0.20 and <n>Υ{hooked}(4 s)=10.81±0.05±0.23.
Original language | English |
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Pages (from-to) | 13-19 |
Number of pages | 7 |
Journal | Zeitschrift für Physik C Particles and Fields |
Volume | 54 |
Issue number | 1 |
DOIs | |
State | Published - Mar 1992 |
Externally published | Yes |