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Pramana

, Volume 41, Supplement 1, pp 55–74 | Cite as

Tests of QCD at LEP

  • Sunanda Banerjee
Standard Model
  • 21 Downloads

Abstract

The four experiments, ALEPH, DELPHI, L3 and OPAL at LEP, have performed a large number of precise measurements to test Quantum Chromodynamics. The strong coupling constant has been measured with high precision:α s (Mz) = 0.123±0.004. The coupling constant has been found to be independent of quark flavour. The running ofα s has been demonstrated by the data. Second order QCD matrix element calculations have been tested from several measured distributions in 3-jet and 4-jet events. These distributions give evidence of the vector nature of the gluon and provide measurements of the QCD colour factors. The hadronic distributions are well reproduced by QCD Monte Carlo programs as well as by analytical calculations with soft gluon coherence effects.

Keywords

Opal Collaboration Strong Coupling Constant Supplement Issue Aleph Collaboration DELPHI Collaboration 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Indian Academy of Sciences 1993

Authors and Affiliations

  • Sunanda Banerjee
    • 1
  1. 1.Tata Institute of Fundamental ResearchBombayIndia

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