Relating physical observables in QCD using the extended renormalization group method
- Department of Physics, University of Maryland, College Park, Maryland 20742 (United States)
- Stanford Linear Accelerator Center, Stanford, California 94309 (United States)
We discuss the Stueckelberg-Peterman extended renormalization group equations in perturbative QCD, which express the invariance of physical observables under renormalization-scale and scheme-parameter transformations. We introduce a universal coupling function that covers all possible choices of scale and scheme. Any perturbative series in QCD is shown to be equivalent to a particular point in this function. This function can be computed from a set of first-order differential equations involving the extended [beta] functions. We propose the use of these evolution equations instead of a perturbative series for numerical evaluation of physical observables. This formalism is free of scale-scheme ambiguity and allows a reliable error analysis of higher-order corrections. It also provides a precise definition for [Lambda][sub M[bar S]] as the pole in the associated 't Hooft scheme. A concrete application to [ital R]([ital e][sup +][ital e[minus]][r arrow]hadrons) is presented.
- DOE Contract Number:
- AC03-76SF00515; FG05-87ER40322
- OSTI ID:
- 6277491
- Journal Information:
- Physical Review, D (Particles Fields); (United States), Vol. 48:7; ISSN 0556-2821
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
QUANTUM CHROMODYNAMICS
PERTURBATION THEORY
CORRECTIONS
COUPLING CONSTANTS
DIFFERENTIAL EQUATIONS
MASSLESS PARTICLES
QUARKS
STRUCTURE FUNCTIONS
ELEMENTARY PARTICLES
EQUATIONS
FERMIONS
FIELD THEORIES
FUNCTIONS
POSTULATED PARTICLES
QUANTUM FIELD THEORY
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662110 - General Theory of Particles & Fields- Theory of Fields & Strings- (1992-)
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