Study of the production properties of the W and Z bosons in panti p collisions and comparison with QCD models

In this thesis the production of the intermediate vector bosons W± and Z0 in panti p collisions has been studied. All obtained results are based on the whole data set which has been taken up in the years 1981-1985 with the UA2 detector at the CERN panti p storage ring at the two center-of-mass energies √s = 546 GeV and √s = 630 GeV. An essential point of this thesis consisted in the study of QCD effects in the production of the vector bosons. For this first the cross sections were determined and compared with QCD calculations. For the comparison with the theories values were used which were calculated in first-order QCD perturbation theory. Within the relative large uncertainties both on theoretical and on experimental side agreement between theory and experiment was achieved. The ratio between the W and Z cross sections has been used to derive limits for the number of the existing neutrino generations. With a confidence level of 95% 7 or more neutrino generations can be excluded. Under the assumption that the mass of the top quark is larger than 74 GeV with the confidence level three neutrino generations are obtained. Also the considered differential cross sections resulted in agreement with the expectations. A further main topic of the thesis was the determination of the strong coupling constant αS. Considered for this was the ratio of the number of the W events with a jet to the number of W events without jet. This ratio was compared with the values which resulted from QCD calculations. As measured value for αS the value was considered for which both ratios agreed. As result in the anti Manti S scheme the value αS(MW2) = 0.13 ± 0.03(stat.) ± 0.02(syst.). (orig./HSI)