Analytic perturbation theory for QCD practitioners and upsilon decay
Abstract
Within ghostfree analytic perturbation theory (APT), devised in the last decade for lowenergy QCD, simple approximations are proposed for threeloop analytic couplings and their effective powers, in both the spacelike (Euclidean) and timelike (Minkowskian) regions, accurate enough in a large range (1100 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 worldaverage value. The issue of scale uncertainty for {gamma} decay is also discussed.
 Authors:
 Joint Institute for Nuclear Research (Russian Federation), Email: 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 ghostfree analytic perturbation theory (APT), devised in the last decade for lowenergy QCD, simple approximations are proposed for threeloop analytic couplings and their effective powers, in both the spacelike (Euclidean) and timelike (Minkowskian) regions, accurate enough in a large range (1100 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 worldaverage 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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