Inclusive - production in e+e- annihilation at 29 GeV has been measured with the Mark II detector. From an integrated luminosity of 207 pb-1, we determine a production rate of 0.0140.0060.004 -, + per hadronic event. This is roughly 35 times the Lund-model prediction of 0.0004 -, + per hadronic event, but comparable to the Webber-model prediction of 0.006 -, + per hadronic event. The large rate of - production, compared with production rates for other baryons, and with theoretical predictions based on diquark models, indicates that spin suppression does not hold for - production. © 1987 The American Physical Society.

We have used a high-resolution drift chamber in the Mark II detector at the SLAC e+e- storage ring PEP to measure the lifetimes of the D0 and D+ mesons produced in e+e- annihilations at 29 GeV. Based on a sample of 74 decays for the D0 mesons and 23 decays for the D+ mesons, the lifetimes are found to be &=(4.7-0.8+0.9) 0.5×10-13 sec and &=(8.9-2.7+3.8) 1.3×10-13 sec. This leads to a ratio of lifetimes &=1.9-0.7 0.3+0.9.. AE © 1986 The American Physical Society.

The charged-particle multiplicities of hadronic events deriving from produced bottom or charm quarks have been measured in the Mark II detector at PEP in e+e- annihilation at 29 GeV. For events containing one semileptonic and one hadronic weak decay, we find multiplicities of 15.20.50.7 for bottom and 13.00.50.8 for charm. The corresponding multiplicities of charged particles accompanying the pair of heavy hadrons are 5.20.50.9 for bottom, and 8.10.50.9 for charm. © 1985 The American Physical Society.

This paper presents a study of events produced in 29-GeV electron-positron annihilation in which there are just two noncollinear charged particles, no detected photons, and two or more undetected particles. These events can be explained by attributing them primarily to the reactions e+e-'e+e-e+e- and e+e-'e+e-+- where just two particles appear in the Mark II detector. There is no evidence for unconventional sources for such events. © 1986 The American Physical Society.

The differential cross sections for lepton pair production in e+e- annihilation at 29 GeV have been measured and found to be in good agreement with the standard model of the electroweak interaction. With the assumption of e-μ-τ universality, the weak neutral-current couplings are determined to be ga2=0.23±0.05 and gv2=0.03±0.04. © 1983 The American Physical Society.

The Production has been investigated by the Mark II collaboration at the SLAC e+e- storage ring PEP. particles are reconstructed by their decay mode. The fragmentation function has been measured and found to be in good agreement with the Lund-model prediction. production has been measured for the first time in high-energy e+e- annihilation. There is evidence at the 3 level for Ds± decay into ± and ±. © 1988 The American Physical Society.

We have set an upper limit on the mass from a study of the four-pion invariant-mass distribution in the decay 3 0. We obtain the limit m <164 MeV/c2 at 95% confidence level. © 1984 The American Physical Society.