RHO-OMEGA-INTERFERENCE IN REACTIONS K-P-]PI+PI-(LAMBDA,SIGMA-0) AT 4.2 GEV-C

π - ω interference is studied in the reactions K- p → π+ π- (Λ0, ε{lunate}) at 4.2 GeV/c using data from a high statistics experiments in the CERN 2m HBC. The phenomenon is analysed in terms of the conventional formalism as well as in terms of a new model for π - ω interference proposed by Earles and Srivastava. Satisfactory agreement with the data is found for both models. The rate of ω → 2π obtained in the latter model is in agreement with the VMD (Vector Meson Dominance) prediction for ω → γ → ρ{variant} → 2π. © 1977

NON-STRANGE VECTOR-MESON PRODUCTION IN K-P INTERACTIONS AT 4.2 GEV-C

The vector meson production, hypercharge exchange reactions K-p → (φ, ω, ρ{variant}) Λ and (φ, ρ{variant}) Σ0 are studied at 4.2 GeV/c incident momentum. The data come from a high statistics bubble chamber experiment with a sensitivity of ∼ 120 events/μb. Total and differential cross sections are presented. The vector meson density matrix elements and hyperon polarization are investigated as functions of momentum transfer. Amplitude analyses are performed for all five reactions. The results are compared with duality and quark model predictions, as well as used to test current ideas in two-body phenomenology. © 1978

MEASUREMENT OF THE AVERAGE LIFETIME OF B-HADRONS

The average lifetime of b hadrons has been measured using the L3 detector at LEP, running at √s ≈ MZ. A b-enriched sample was obtained from 432538 hadronic Z events collected in 1990 and 1991 by tagging electrons and muons from semileptonic b hadron decays. From maximum likelihood fits to the electron and muon impact parameter distributions, the average b hadron lifetime was measured to be τb = (1535 ± 35 ± 28) fs, where the first error is statistical and the second includes both the experimental and the theoretical systematic uncertainties. © 1993

A MEASUREMENT OF tau-POLARIZATION AT LEP

With a data sample of 86 000 Z → τ+τ-(γ) events collected in 1990 through 1993 we have measured the polarization of τ-leptons as a function of the production polar angle using the following 1-prong τ decay modes: τ-→e-vevτ, τ-→π- (K-)vτ, τ-→ρ{variant}-vτ and τ-→a1-vτ. We obtain for the ratio vector to axial-vector weak neutral couplings for electrons gVe/gAe=0.0791±0.0099(stat)±0.0025 (syst) and taus gVτ/gAτ=0.0752±0.0063 (stat)±0.0045 (syst) consistent with the hypothesis of e - τ universality. Assuming universality of the e - τ neutral current we determine the effective electroweak mixing angle to be sin2 θeffw = 0.2309 ± 0.0016. © 1994

AN IMPROVED MEASUREMENT OF B(0)-(B)BAR(0) MIXING IN Z(0) DECAYS

A more precise determination of the B0-B0 mixing parameter in Z0 decays based on a fourfold increase in statistics has been made using the 1990 and 1991 L3 data. The analysis of the dilepton events, muons and electrons, gives: χB = 0.121 ± 0.017 (stat) ± 0.006 (sys). Using the value of χd measured at the γ(4S) we derive the following limit for χs:χs > 0.16 (90% CL). © 1992