Latest Results from the Mark Ii at Pep* Nigellockyer
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چکیده
i We present single photon annihilation results from the MARK II detector at PEP based on 100 pb-l of integrated luminosity taken at a center of mass energy fi = 29 GeV. A study of inclusive leptons for momenta 2 2 GeV/c yield the average semileptonic branching ratios of bottom (b) and charm (c) quarks and information about the b fragmentation function. A measurement of the bottom hadron lifetime is presented based on a study of the prompt lepton impact parameters. In addition we report on a precise measurement of the tau lifetime and an updated Do lifetime. We also present a search for supersymmetric electrons, w.eak neutral current couplings from leptons-and bottom particles and evidence for K*‘s at PEP.
منابع مشابه
Recent Results from the Mark Ii Experiment+
The Mark II experiment first started taking data in 1978 at the SLAC SPEAR storage ring. It was the first e+edetector with a large, many layer cylindrical drift chamber (CDC) and a large liquid argon calorimeter!” After two years at SPEAR, it was moved to the PEP storage ring, where it was upgraded a year later with a seven layer precision vertex drift chamber!’ located between the CDC and the ...
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