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Title: Analytic perturbation theory for QCD practitioners and upsilon decay

Abstract

Within ghost-free analytic perturbation theory (APT), devised in the last decade for low-energy QCD, simple approximations are proposed for three-loop analytic couplings and their effective powers, in both the spacelike (Euclidean) and timelike (Minkowskian) regions, accurate enough in a large range (1-100 GeV) of current physical interest. Effectiveness of the new model is illustrated by the example of {gamma}(1S) decay, where a standard analysis gives {alpha}{sub s}(M{sub {gamma}}) = 0.170 {+-} 0.004, which is inconsistent with the bulk of data on {alpha}{sub s}. Instead, we obtain {alpha}{sub s}{sup mod}(M{sub {gamma}}) = 0.185 {+-} 0.005, which corresponds to {alpha}{sub s}{sup mod}(M{sub Z} = 0.120 {+-} 0.002, which is close to the world-average value. The issue of scale uncertainty for {gamma} decay is also discussed.

Authors:
;  [1]
  1. Joint Institute for Nuclear Research (Russian Federation), E-mail: zayakin@theor.jinr.ru
Publication Date:
OSTI Identifier:
21075887
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Atomic Nuclei; Journal Volume: 70; Journal Issue: 4; Other Information: DOI: 10.1134/S1063778807040205; Copyright (c) 2007 Nauka/Interperiodica; Article Copyright (c) 2007 Pleiades Publishing, Ltd; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; APPROXIMATIONS; COUPLINGS; EUCLIDEAN SPACE; GAMMA DECAY; GEV RANGE; MINKOWSKI SPACE; PERTURBATION THEORY; QUANTUM CHROMODYNAMICS

Citation Formats

Shirkov, D. V., and Zayakin, A. V. Analytic perturbation theory for QCD practitioners and upsilon decay. United States: N. p., 2007. Web. doi:10.1134/S1063778807040205.
Shirkov, D. V., & Zayakin, A. V. Analytic perturbation theory for QCD practitioners and upsilon decay. United States. doi:10.1134/S1063778807040205.
Shirkov, D. V., and Zayakin, A. V. Sun . "Analytic perturbation theory for QCD practitioners and upsilon decay". United States. doi:10.1134/S1063778807040205.
@article{osti_21075887,
title = {Analytic perturbation theory for QCD practitioners and upsilon decay},
author = {Shirkov, D. V. and Zayakin, A. V.},
abstractNote = {Within ghost-free analytic perturbation theory (APT), devised in the last decade for low-energy QCD, simple approximations are proposed for three-loop analytic couplings and their effective powers, in both the spacelike (Euclidean) and timelike (Minkowskian) regions, accurate enough in a large range (1-100 GeV) of current physical interest. Effectiveness of the new model is illustrated by the example of {gamma}(1S) decay, where a standard analysis gives {alpha}{sub s}(M{sub {gamma}}) = 0.170 {+-} 0.004, which is inconsistent with the bulk of data on {alpha}{sub s}. Instead, we obtain {alpha}{sub s}{sup mod}(M{sub {gamma}}) = 0.185 {+-} 0.005, which corresponds to {alpha}{sub s}{sup mod}(M{sub Z} = 0.120 {+-} 0.002, which is close to the world-average value. The issue of scale uncertainty for {gamma} decay is also discussed.},
doi = {10.1134/S1063778807040205},
journal = {Physics of Atomic Nuclei},
number = 4,
volume = 70,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}
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