Application of 'Optimised' Perturbation Theory to Determination of alpha_s(M_Z^2) from Hadronic Event Shape Observables in e+e- Annihilation

Abstract

We have applied so-called `optimised' perturbation theory to resolve the renormalisation-scale (mu) ambiguity of exact O(alpha_s^2) QCD calculations of event shape observables in e+e- --> hadrons. We fitted the optimised predictions for 15 observables to hadronic Z0 decay data from the SLD experiment to determine alpha_s(M_Z^2). Comparing with results using the physical scale mu = M_Z we found no reduction in the scatter among alpha_s(M_Z^2) values from the 15 observables, implying that the O(alpha_s^2) predictions with optimised scales are numerically no closer to the exact all-orders results than those with the physical scale.

19 pages for text plus 4 pages for figures which were tar'ed, gzip'ed, uuencoded and put as one package. Original text is in PS format and original figures are in EPS format

References in corpus (1)

• Measurement of alpha_s(M_Z^2) from Hadronic Event Observables at the Z^0 Resonance

Cited by in corpus (7)

• First determination of the strong coupling constant using NNLO predictions for hadronic event shapes in e^+e^- annihilations
• Tests of Quantum Chromo Dynamics at e^+e^- Colliders
• Measurement of the running b-quark mass using $e^{+}{e}^{-}\to b\bar{b}g$ events
• Probing Transverse Momentum Dependent Structures with Azimuthal Dependence of Energy Correlators
• Application of Pade Approximants to Determination of alpha_s(M_Z^2) from Hadronic Event Shape Observables in e+e- Annihilation
• Effective Charges in Practice
• Review on alpha_s at LEP