A measurement of the weak axial couplings of theb- andc-quark

The forward-backward charge asymmetries of theb andc quarks are measured with the JADE detector at PETRA at s√=35 GeV and 44 GeV using both electrons and muons to tag the heavy quarks. At s√=35 GeV, a simultaneous fit for the two asymmetries yields the resultA b =−9.3±5.2% (state.) ndA c =−9.6±4.0% (stat.). The systematic errors are comparable with the statistical uncertainties. Combining the measurements at both energies and alternately constraining the weak coupling of thec andb quark to their Standard Model values (a c =1,a b =−1) increases the precision of the measurement of coupling constant of the other quark. Using this procedurea b =−0.72±0.34 anda c =0.79±0.40, where the numbers are corrected for BBˉ−mixing and the errors include both statistical and systematic contributions. The mixing parameter for continuum bbˉ−production is determined to be χ-0.24±0.12 if both heavy quark coupling constants are constrained to their values in the Standard Model

A measurement of the τ lepton lifetime

The lifetime of the τ lepton was measured using two different techniques. From the impact parameter distribution of 3132 one prong decays ττ = (289±33±26) fs was obtained and from the decay length distribution of 648 three prong decays ττ = (309 −34 +35±11) fs. These results were combined to give a final value of ττ = (301±29) fs

Measurement of two photon production of rho0 omega

The reaction γγ→π+π-π+π-π0 has been studied using the JADE detector at PETRA. The cross sections for γγ→ωπ+ - and for γγ→ωρ0 - are given. We observe no peak in these cross sections in the regionW γγ=1.9–2.0 GeV

Radiative τ pair production and search for new particles decaying into τ

A study of radiative τ pair production,e + e −→τ+τ−γ ande + e −→τ+τ−γγ, is presented. The observed events agree with QED predictions of order α3 and α4. Excited τ′s have been searched for and lower limits on single and pair production are obtained. For QED-like coupling the τ* mass is limited to values greater than 40 GeV (95% CL). A search for unstable charged scalars (S ±) decaying into τ, e.g. charged Higgs, technipions or the supersymmetric partners of τ′s, yields no evidence for such particles. Assuming a branching fraction ofB(S→τν)=1,S masses up to 18.7 GeV are excluded with 95% CL

Determination of the B lifetime

We have determined the lifetime of B-hadrons produced ine + e − annihilation into multihadronic final states, by measuring the impact parameter of the track with respect to the centre of the interaction region. Two different analyses of the data were performed and gave compatible results. The lifetime is τ B =1.8 −0.4 +0.5±0.4 ps