Direct Tests of Quantum Chromodynamics in High  ElectronPositron Annihilation at PETRA.
Abstract
With the TASSO detector at PETRA, we have studied QCD effects in the hadronic channel of e('+)e(') annihilation. In addition to events with 2 jets of hadrons, we have observed 3jet events which are naturally described in the context of QCD as manifestations of the process e('+)e(') ( >) qqg. By studying distributions sensitive to the rate of 3jet production in the range of 27 GeV < W < 37 GeV, we determined the strong coupling constant, (alpha)(,s) to be. (alpha)(,s) = 0.17 (+OR) 0.01 (+OR) 0.03. where 0.01 is the statistical error, and 0.03 is the systematic error. Comparing predictions of QCD models with the data, we found that the models accurately described the observed energy dependence of numerous distributions, as well as detailed properties of 3jet events. By studying angular distributions of jet axes in 3jet events, we found that our data were consistent with spin1 gluons (0.9(sigma)) while being in strong disagreement with the hypothesis of spin0 gluons (4.5(sigma)).
 Publication:

Ph.D. Thesis
 Pub Date:
 1981
 Bibcode:
 1981PhDT........49F
 Keywords:

 Physics: Elementary Particles and High Energy