The results on strong coupling constant, alpha(s), in e(+)e(-) collision at LEP are reviewed, based on hadronic events collected at centre-of-mass energies between 30 GeV and 208 GeV by the L3 experiment. In particularly the recent results at roots greater than or equal to 192 GeV are discussed. The distributions of several event shape variables are compared to resummed O(alpha(s)(2)) QCD calculations. These measurements, combined with previous L3 measurements at lower energies, demonstrate the running of alpha(s) as expected in QCD and yield alpha(s)(mz) = 0.1227 +/- 0.0012 +/- 0.0058, where the first uncertainty is experimental and the second is theoretical.
Determination of alpha(s) at LEP by L3 experiment / Gentile, Simonetta. - In: NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS. - ISSN 0920-5632. - 121:(2003), pp. 55-58. (Intervento presentato al convegno 9th High-Energy Physics International Conference on Quantum ChromoDynamics tenutosi a MONTPELLIER, FRANCE nel JUL 02-09, 2002).
Determination of alpha(s) at LEP by L3 experiment.
GENTILE, Simonetta
2003
Abstract
The results on strong coupling constant, alpha(s), in e(+)e(-) collision at LEP are reviewed, based on hadronic events collected at centre-of-mass energies between 30 GeV and 208 GeV by the L3 experiment. In particularly the recent results at roots greater than or equal to 192 GeV are discussed. The distributions of several event shape variables are compared to resummed O(alpha(s)(2)) QCD calculations. These measurements, combined with previous L3 measurements at lower energies, demonstrate the running of alpha(s) as expected in QCD and yield alpha(s)(mz) = 0.1227 +/- 0.0012 +/- 0.0058, where the first uncertainty is experimental and the second is theoretical.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
