The Tau Neutrino Mass and the Michel Parameter in Tau Decay.

The Michel parameter, an indication of the V +/- A nature of a decay vertex, was measured using the decays tauto{ rm e}nu|nu and tautomunu|nu. An upper limit was obtained for the mass of the tau neutrino, nu_tau. These measurements were made using the CLEO detector at the Cornell Electron Storage Ring. The measurement of the Michel parameter is the first measurement to include muons in the analysis. The final value,.71 +/-.09 +/- .03, agrees well with V-A coupling, and is in agreement with previous measurements. This result has been published elsewhere.^1. The upper limit obtained for the tau neutrino mass was accomplished through missing neutral energy studies. A sample of taus were produced in the reaction eetotautaugamma , where the photon comes from initial state radiation. One tau subsequently decays as tautopipipi npi ^ 0 (n >= 0). The 95% confidence level upper limit is 85.0 MeV/c^ 2, which agrees with previous results using similar techniques. This analysis represents an improvement because of the detailed study of the systematic errors involved, and has also been published elsewhere.^ 2 ftn ^{1,2}Please see dissertation for references.