Measurement of Z0 decays to hadrons, and a precise determination of the number of neutrino species

We have made a precise measurement of the cross section for e+e--->Z0-->hadrons with the L3 detector at LEP, covering the range from 88.28 to 95.04 GeV. From a fit to the Z0 mass, total width, and the hadronic cross section to be MZ0=91.160 +/- 0.024 (experiment) +/-0.030(LEP) GeV, [Gamma]Z0=2.539+/-0.054 GeV, and [sigma]h(MZ0)=29.5+/-0.7 nb. We also used the fit to the Z0 peak cross section and the width todetermine [Gamma]invisible=0.548+/-0.029 GeV, which corresponds to 3.29+/-0.17 species of light neutrinos. The possibility of four or more neutrino flavors is thus ruled out at the 4[sigma] confidence level.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/28683/3/0000500.pd

A measurement of the Z0 leptonic partial widths and the vector and axial vector coupling constants

We have measured the partial widths of the Z0 into lepton pairs, and the forward-backward charge asymmetry for the process e+e--->[mu]+[mu]- using the L3 detector at LEP. We obtain an average [Gamma]ll of 83.0+/-2.1+/-1.1 MeV.From this result and the asymmetry measurement, we extract the values of the vector and axial vector couplings of the Z0 to leptons: grmv=-0.066-0.027+0.046 and grmA= -0.495-0.007+0.007.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/28666/3/0000483.pd

Determination of αs\alpha_{s} from jet multiplicities measured on the Z0^{0} resonance

Whatever the field, major change implies as much as deep transformation of thinking i.e to put in network new skills in particular, those made available by the availability of new technologies. In this context, only one individual cannot join together all necessary skills. It becomes clear that the goal of space valorization cannot be considered without relational investment between the partners and their accumulated background. The local empowerment concerns a collective phenomenon of acquisition and development of skills rests on an learning way appropriate to the potential of the territory to form or promote. The local mediation sets for objective the creation of relations between pre-existent skills and their transfer between the actors, individuals or groups, private or public. But the capacity of the territory to solve these problems will depend closely on the richness of the network and co-operations which it shelters or it will suggest