Qcd Studies at Lep I
نویسنده
چکیده
The high hadronic event statistics collected at the Z energy (LEP I) allowed a good understanding of the QCD dynamics. The coupling constant s has been measured with several methods giving a global average s (M Z) = 0:122 0:004. The avour independence of s has been tested obtaining b s == udsc s = 0:997 0:023. Quark-gluon jet diierencies has been observed among which < n > gluon = < n > quark = 1:234 0:027. A big role has been plaied by the silicon vertex detectors.
منابع مشابه
ar X iv : h ep - e x / 04 06 05 8 v 1 2 2 Ju n 20 04 QCD Studies at LEP
Studies of hadronic final states of e + e − annihilations at LEP are reviewed. The topics included cover hadronic event shapes, measurements of αs, determinations of QCD colour factors and tests of the non-Abelian gauge structure of QCD, differences between quark and gluon jets, QCD with heavy quarks and selected results of two-photon scattering processes.
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