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Title: A Systematic Study of QCD Coupling Constant from Deep-Inelastic Measurements

Abstract

We reanalyze deep-inelastic scattering data of the BCDMS Collaboration by including proper cuts of ranges with large systematic errors. We also perform the fits of high-statistic deep-inelastic scattering data of the BCDMS, SLAC, NM, and BFP Collaborations taking the data separately and in a combined way and find good agreement between these analyses. We extract the values of both the QCD coupling constant {alpha}{sub s}(M{sup 2}{sub Z}) up to the NLO level and of the power corrections to the structure function F{sub 2}. The fits of the combined data for the nonsinglet part of the structure function F{sub 2} predict the coupling constant value {alpha}{sub s}(M{sup 2}{sub Z}) = 0.1174 {+-} 0.0007 (stat.) {+-} 0.0019 (syst.) {+-} 0.0010 (norm.) (or QCD parameter {lambda}{sup (5)}{sub MS} = 204 {+-} 25 (total experimental error) MeV). The fits of the combined data for both the nonsinglet part and the singlet part lead to the values {alpha}{sub s}(M{sup 2}{sub Z}) = 0.1177 {+-} 0.0007 (stat.) {+-} 0.0021 (syst.) {+-} 0.0009 (norm.) (or QCD parameter {lambda}{sup (5)}{sub MS} = (208 {+-} 27 (total experimental error) MeV). The above values are in very good agreement with each other. We estimate theoretical uncertainties for {alpha}{sub s}(M{sup 2}{submore » Z}) at +0.0047 and -0.0057 from fits of the combined data when complete singlet and nonsinglet Q{sup 2} evolution is taken into account.« less

Authors:
;  [1]
  1. Joint Institute for Nuclear Research, Dubna, Moscow oblast, 141980 (Russian Federation)
Publication Date:
OSTI Identifier:
20692908
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Atomic Nuclei; Journal Volume: 68; Journal Issue: 11; Other Information: Translated from Yadernaya Fizika, ISSN 0044-0027, 68, 1935-1965 (No. 11, 2005); DOI: 10.1134/1.2131117; (c) 2005 Pleiades Publishing, Inc; Country of input: International Atomic Energy Agency (IAEA); TN:
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CORRECTIONS; COUPLING CONSTANTS; DATA ANALYSIS; DEEP INELASTIC SCATTERING; ERRORS; MEV RANGE; QUANTUM CHROMODYNAMICS; STRUCTURE FUNCTIONS

Citation Formats

Krivokhizhin, V.G., and Kotikov, A.V. A Systematic Study of QCD Coupling Constant from Deep-Inelastic Measurements. United States: N. p., 2005. Web. doi:10.1134/1.2131117.
Krivokhizhin, V.G., & Kotikov, A.V. A Systematic Study of QCD Coupling Constant from Deep-Inelastic Measurements. United States. doi:10.1134/1.2131117.
Krivokhizhin, V.G., and Kotikov, A.V. Tue . "A Systematic Study of QCD Coupling Constant from Deep-Inelastic Measurements". United States. doi:10.1134/1.2131117.
@article{osti_20692908,
title = {A Systematic Study of QCD Coupling Constant from Deep-Inelastic Measurements},
author = {Krivokhizhin, V.G. and Kotikov, A.V.},
abstractNote = {We reanalyze deep-inelastic scattering data of the BCDMS Collaboration by including proper cuts of ranges with large systematic errors. We also perform the fits of high-statistic deep-inelastic scattering data of the BCDMS, SLAC, NM, and BFP Collaborations taking the data separately and in a combined way and find good agreement between these analyses. We extract the values of both the QCD coupling constant {alpha}{sub s}(M{sup 2}{sub Z}) up to the NLO level and of the power corrections to the structure function F{sub 2}. The fits of the combined data for the nonsinglet part of the structure function F{sub 2} predict the coupling constant value {alpha}{sub s}(M{sup 2}{sub Z}) = 0.1174 {+-} 0.0007 (stat.) {+-} 0.0019 (syst.) {+-} 0.0010 (norm.) (or QCD parameter {lambda}{sup (5)}{sub MS} = 204 {+-} 25 (total experimental error) MeV). The fits of the combined data for both the nonsinglet part and the singlet part lead to the values {alpha}{sub s}(M{sup 2}{sub Z}) = 0.1177 {+-} 0.0007 (stat.) {+-} 0.0021 (syst.) {+-} 0.0009 (norm.) (or QCD parameter {lambda}{sup (5)}{sub MS} = (208 {+-} 27 (total experimental error) MeV). The above values are in very good agreement with each other. We estimate theoretical uncertainties for {alpha}{sub s}(M{sup 2}{sub Z}) at +0.0047 and -0.0057 from fits of the combined data when complete singlet and nonsinglet Q{sup 2} evolution is taken into account.},
doi = {10.1134/1.2131117},
journal = {Physics of Atomic Nuclei},
number = 11,
volume = 68,
place = {United States},
year = {Tue Nov 01 00:00:00 EST 2005},
month = {Tue Nov 01 00:00:00 EST 2005}
}
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