On the applicability of finite order perturbative QCD calculations of jet rates ine + e ? annihilation

• DOI: 10.1007/bf01411015
• Publication Date: 2005-04-03T04:10:29Z
• Authors: P. N. Burrows; H. Masuda
• Keywords: Annihilation; Perturbative QCD; Matrix element

We have studied the measurement of α s using exact second order QCD matrix element calculations of jet rates ine + e −→hadrons. We investigate the dependence of α s (M 2 ), measured by experiments at theZ 0 resonance, on the choice of renormalisation scale in terms of the functional form of the three-jet matrix element. We find that only a restricted domain of the jet resolution parametery c , $$\Lambda _{\overline {MS} } $$ , and scale gives a perturbation series which is well-behaved to second order, and that this domain is different for the various jet algorithms in current use.