Study of hadronic event shape in flavour tagged events in $e^+ e^-$ annihilation at < s**(1/2) > = 197-GeV

Results are presented from a study of the structure of hadronic events in high-energy e+e- interactions detected by the L3 detector at LEP. Various event shape distributions and their moments are measured at several energy points at and above the Z-boson mass. The event flavour is tagged by using the decay characteristics of b-hadrons. Measurements of distributions of event shape variables for all hadronic events, for light (u, d, s, c) and heavy (b) quark flavours are compared to several QCD models with improved leading log approximation: JETSET, HERWIG and ARIADNE. A good description of the data is provided by the models.

Note:

29 pages, 9 figures

13.66.Bc
12.38.Qk
event shape analysis
CERN LEP Stor
L3
parton: showers
electron positron: annihilation
quark: pair production
hadron: multiple production
energy dependence

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