QCD studies at LEP

Qcd Studies at Lep I

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 =...

QCD at LEP*

Qcd at Lep

This lecture is a brief introductory to QCD at Lep. It is shown, how the basic properties of strongly interacting elds have been veriied at Lep and how the strong coupling is measured from event shapes. Important properties of the hadronic nal state, namely the energy evolution of fragmentation functions and of multiplici-ties as well as the importance of coherence eeects are discussed. The con...

Final state QCD studies at LEP: Part II

We review two studies of γγ collisions performed by DELPHI at LEP2, the first on single particle inclusive production, the second on di-jet production. We also briefly highlight the comprehensive study of e + e − → q ¯ q events performed by L3 at LEP1 and LEP2.

Review of QCD at LEP

We review the first round of QCD studies at the c+ ecollider LEP, which started operating towards the end of last year. These studies at the peak of the 2’ resonance have proven to be extremely rewarding, not only because of the large statistics available due to the high resonance cross section, but also because of the higher centre of mass energy, which allows a much cleaner study of events wi...