Application of Pade Approximants to Determination of alpha_s(M_Z^2) from Hadronic Event Shape Observables in e+e- Annihilation

Abstract

We have applied Pade approximants to perturbative QCD calculations of event shape observables in e+e- --> hadrons. We used the exact O(alpha_s^2) prediction and the [0/1] Pade approximant to estimate the O(alpha_s^3) term for 15 observables, and in each case determined alpha_s(M_Z^2) from comparison with hadronic Z^0 decay data from the SLD experiment. We found the scatter among the alpha_s(M_Z^2) values to be significantly reduced compared with the standard O(alpha_s^2) determination, implying that the Pade method provides at least a partial approximation of higher-order perturbative contributions to event shape observables.

15 pages, 1 EPS figure, Submitted to Physics Letters B

References in corpus (10)

• Comparison of the Pade Approximation Method to Perturbative QCD Calculations
• Measurement of alpha_s(M_Z^2) from Hadronic Event Observables at the Z^0 Resonance
• Pade Approximants, Borel Transforms and Renormalons: the Bjorken Sum Rule as a Case Study
• Determining ${\alpha }_s$ from Measurements at $Z$: How Nature Prompts us about New Physics
• A Global Fit of LEP/SLC Data with Light Superpartners
• Lowering alpha_s by flipping SU(5)
• Application of 'Optimised' Perturbation Theory to Determination of alpha_s(M_Z^2) from Hadronic Event Shape Observables in e+e- Annihilation
• A low ${\alpha }_s$ and its consequences for unified model building
• A low α_s: Hint of new physics at the GUT scale?
• ${\alpha }_s(M_Z^2)$ and $R_b$ discrepancy with nonuniversal interactions

Cited by in corpus (5)

• The QCD Renormalization Group Equation and the Elimination of Fixed-Order Scheme-and-Scale Ambiguities Using the Principle of Maximum Conformality
• Extending the Predictive Power of Perturbative QCD
• Asymptotic Improvement of Resummation and Perturbative Predictions in Quantum Field Theory
• The heavy quarkonium inclusive decays using the principle of maximum conformality
• Using an Effective Charges Method to extract Lambda-MS-bar from event shape moments in e+e- annihilation