Search

107 pp. (1981).

21 pp. (1978)., Decays of the heavy lepton τ have now been observed in e+e− ‐ collisions at the energy of the ψ′‐resonace, which results in an improved mass determination Mτ=1.807±0.020 GeV. For the τ‐life‐time a new upper limit of ττ?3.5⋅10−12 sec. is given. The evidence for the decay τ→νπρ has been strengthened, and the πρ‐system is found to be in an S‐wave state with JP=1+, proving the axial vector component in the leptonic coupling of the τ to hadrons. The branching ratio is given with BR(τ−→νπ−ρ0) =0.050±0.015. The total hadronic cross section agrees within errors with the quarksum rule including QCD‐corrections. The production and decay distributions of the decay J/ψ→f0γ have been measured and found to agree well with a QCD calculation based on the exchange of two gluons.

30 pp. (1979).

Gluons 28 pp. (1981)., The production of hard noncollinear gluons in short distance processes is disussed, with emphasis on recent results from e+e− interactions. The jet phenomena observed in the e+e− continuum and in Υ decay are consistently described as due to the emission of QCD gluons while alternative explanations fail. The vector and color‐nonsinglet nature of the radiated quanta is directly verified.

(1977). doi:10.1016/0370-2693(77)90708-0, As a test of quantum chromodynamics (QCD), we suggest looking for gluon jets in the decay of a heavy quark-antiquark bound state produced in e + e − annihilation, Q Q → 3 gluons → 3 gluon jets. In particular, we point out that these events form a jet Dalitz plot, and we calculate the gluon or jet distributions (including the effect of polarized e + e − beams). This process affords a test of the gluon spin. It is the analogue of two-jet angular distributions in e + e − → q q → 2 quark jets. We also estimate multiplicities and momentum distributions of hadrons in Q Q → 3 gluons → hadrons , using the recently discovered ϒ(9.4) as an example.