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Title: Novel method for the precise determination of the QCD running coupling from event shape distributions in electron-positron annihilation

Abstract

We present a novel method for precisely determining the running QCD coupling constant α s ( Q 2 ) over a wide range of Q 2 from event shapes for electron-positron annihilation measured at a single annihilation energy s . The renormalization scale Q 2 of the running coupling depends dynamically on the virtuality of the underlying quark and gluon subprocess and thus the specific kinematics of each event. The determination of the renormalization scale for event shape distributions is obtained by using the principle of maximum conformality (PMC), a rigorous scale-setting method for gauge theories which satisfies all the requirements of renormalization group invariance, including renormalization-scheme independence and consistency with Abelian theory in the N C 0 limit. In this paper, we apply the PMC to two classic event shapes measured in e + e annihilation: the thrust ( T ) and C-parameter ( C ). The PMC renormalization scale depends differentially on the values of T and C . The application of PMC scale-setting determines the running coupling α s ( Q 2 ) to high precision over a wide range of Q 2 from 10 to 250 GeV 2 from measurements of the event shape distributions at the Z 0 peak. The extrapolation of the running coupling using pQCD evolution gives the value α s ( M Z 2 ) = 0.1185 ± 0.0012 from the thrust and α s ( M Z 2 ) = 0.119 3 0.0019 + 0.0021 from the C-parameter in the MS ¯ scheme. These determinations of α s ( M Z 2 ) are consistent with the world average and are more precise than the values obtained from analyses of event shapes currently used in the world average. The highly consistent results for the T and C event-shape distributions provide an additional verification of the applicability of the PMC to pQCD.

Authors:
ORCiD logo; ORCiD logo; ; ORCiD logo;
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE; Natural Science Foundation of China
OSTI Identifier:
1573861
Alternate Identifier(s):
OSTI ID: 1596796
Report Number(s):
SLAC-PUB-17458; arXiv:1908.00060v2
Journal ID: ISSN 2470-0010; PRVDAQ; 094010
Grant/Contract Number:  
AC02-76SF00515; SLAC-PUB-17458; 11625520; 11705033; 11847301; 11905056; KY[2016]028; KY[2017]067
Resource Type:
Published Article
Journal Name:
Physical Review D
Additional Journal Information:
Journal Name: Physical Review D Journal Volume: 100 Journal Issue: 9; Journal ID: ISSN 2470-0010
Publisher:
American Physical Society
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Citation Formats

Wang, Sheng-Quan, Brodsky, Stanley J., Wu, Xing-Gang, Shen, Jian-Ming, and Di Giustino, Leonardo. Novel method for the precise determination of the QCD running coupling from event shape distributions in electron-positron annihilation. United States: N. p., 2019. Web. doi:10.1103/PhysRevD.100.094010.
Wang, Sheng-Quan, Brodsky, Stanley J., Wu, Xing-Gang, Shen, Jian-Ming, & Di Giustino, Leonardo. Novel method for the precise determination of the QCD running coupling from event shape distributions in electron-positron annihilation. United States. doi:10.1103/PhysRevD.100.094010.
Wang, Sheng-Quan, Brodsky, Stanley J., Wu, Xing-Gang, Shen, Jian-Ming, and Di Giustino, Leonardo. Mon . "Novel method for the precise determination of the QCD running coupling from event shape distributions in electron-positron annihilation". United States. doi:10.1103/PhysRevD.100.094010.
@article{osti_1573861,
title = {Novel method for the precise determination of the QCD running coupling from event shape distributions in electron-positron annihilation},
author = {Wang, Sheng-Quan and Brodsky, Stanley J. and Wu, Xing-Gang and Shen, Jian-Ming and Di Giustino, Leonardo},
abstractNote = {We present a novel method for precisely determining the running QCD coupling constant αs(Q2) over a wide range of Q2 from event shapes for electron-positron annihilation measured at a single annihilation energy s. The renormalization scale Q2 of the running coupling depends dynamically on the virtuality of the underlying quark and gluon subprocess and thus the specific kinematics of each event. The determination of the renormalization scale for event shape distributions is obtained by using the principle of maximum conformality (PMC), a rigorous scale-setting method for gauge theories which satisfies all the requirements of renormalization group invariance, including renormalization-scheme independence and consistency with Abelian theory in the NC→0 limit. In this paper, we apply the PMC to two classic event shapes measured in e+e– annihilation: the thrust (T) and C-parameter (C). The PMC renormalization scale depends differentially on the values of T and C. The application of PMC scale-setting determines the running coupling αs(Q2) to high precision over a wide range of Q2 from 10 to 250 GeV2 from measurements of the event shape distributions at the Z0 peak. The extrapolation of the running coupling using pQCD evolution gives the value αs(MZ2)=0.1185±0.0012 from the thrust and αs(MZ2)=0.1193–0.0019+0.0021 from the C-parameter in the MS¯ scheme. These determinations of αs(MZ2) are consistent with the world average and are more precise than the values obtained from analyses of event shapes currently used in the world average. The highly consistent results for the T and C event-shape distributions provide an additional verification of the applicability of the PMC to pQCD.},
doi = {10.1103/PhysRevD.100.094010},
journal = {Physical Review D},
number = 9,
volume = 100,
place = {United States},
year = {2019},
month = {11}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record
DOI: 10.1103/PhysRevD.100.094010

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Works referenced in this record:

Moments of event shapes in electron-positron annihilation at next-to-next-to-leading order
journal, November 2009


Superinclusive cross sections
journal, March 1978


Commensurate scale relations in quantum chromodynamics
journal, April 1995


C -parameter distribution at N 3 LL including power corrections
journal, May 2015


Precise determination of α s from the C -parameter distribution
journal, May 2015


BLM scale fixing in event-shape distributions
journal, June 2014


The principal axis of jets — an attempt to analyse high-energy collisions as two-body processes
journal, September 1964


Padé approximants, Borel transforms and renormalons: the Bjorken sum rule as a case study
journal, January 1996


Systematic All-Orders Method to Eliminate Renormalization-Scale and Scheme Ambiguities in Perturbative QCD
journal, May 2013


Systematic scale-setting to all orders: The principle of maximum conformality and commensurate scale relations
journal, January 2014


Thrust distribution in electron-positron annihilation using the principle of maximum conformality
journal, June 2019


The QCD renormalization group equation and the elimination of fixed-order scheme-and-scale ambiguities using the principle of maximum conformality
journal, September 2019


Determination of the strong coupling constant using matched NNLO+NLLA predictions for hadronic event shapes in e + e annihilations
journal, August 2009


Thrust at N 3 LL with power corrections and a precision global fit for α s ( m Z )
journal, April 2011


Tensor analysis of hadronic jets in quantum chromodynamics
journal, December 1979


A precise determination of α s from LEP thrust data using effective field theory
journal, July 2008


Study of moments of event shapes and a determination of α S using e+e− annihilation data from JADE
journal, February 2009


Quantum Electrodynamics at Small Distances
journal, September 1954


Setting the renormalization scale in QCD: The principle of maximum conformality
journal, October 2012


Study of moments of event shapes and a determination of α S using e+e− annihilation data from JADE
journal, May 2009


NNLO moments of event shapes in e + e annihilation
journal, May 2009


RunDec: a Mathematica package for running and decoupling of the strong coupling and quark masses
journal, December 2000


NNLO corrections to event shapes in e + e annihilation
journal, December 2007


Event shapes and jet rates in electron-positron annihilation at NNLO
journal, June 2009


Review of Particle Physics
journal, August 2018


Self-consistency requirements of the renormalization group for setting the renormalization scale
journal, September 2012


Quantum Chromodynamics Test for Jets
journal, December 1977


EERAD3: Event shapes and jet rates in electron–positron annihilation at order α s 3
journal, December 2014

  • Gehrmann-De Ridder, A.; Gehrmann, T.; Glover, E. W. N.
  • Computer Physics Communications, Vol. 185, Issue 12
  • DOI: 10.1016/j.cpc.2014.07.024

Renormalization group invariance and optimal QCD renormalization scale-setting: a key issues review
journal, October 2015


Conformal collider physics: energy and charge correlations
journal, May 2008


On the elimination of scale ambiguities in perturbative quantum chromodynamics
journal, July 1983

  • Brodsky, Stanley J.; Lepage, G. Peter; Mackenzie, Paul B.
  • Physical Review D, Vol. 28, Issue 1
  • DOI: 10.1103/PhysRevD.28.228

Eliminating the Renormalization Scale Ambiguity for Top-Pair Production Using the Principle of Maximum Conformality
journal, July 2012


Jet production rates at LEP and the scale of ?s
journal, March 1991

  • Kramer, G.; Lampe, B.
  • Zeitschrift f�r Physik A Hadrons and Nuclei, Vol. 339, Issue 1
  • DOI: 10.1007/BF01282948

The dipole formalism for the calculation of QCD jet cross sections at next-to-leading order
journal, June 1996


Aspects of SU(Nc) gauge theories in the limit of small number of colors
journal, January 1998