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Title: Momentum flow correlations from event shapes: Factorized soft gluons and soft-collinear effective theory

Abstract

The distributions of two-jet event shapes contain information on hadronization in QCD. Near the two-jet limit, these distributions can be described by convolutions of nonperturbative event shape functions with the same distributions calculated in resummed perturbation theory. The shape functions, in turn, are determined by correlations of momentum flow operators with each other and with lightlike Wilson lines, which describe the coupling of soft, wide-angle radiation to jets. We observe that leading power corrections to the mean values of event shapes are determined by the correlation of a single momentum flow operator with the relevant Wilson lines. This generalizes arguments for the universality of leading power corrections based on the low-scale behavior of the running coupling or resummation. We also show how a study of the angularity event shapes can provide information on correlations involving multiple momentum flow operators, giving a window to the system of QCD dynamics that underlies the variety of event shape functions. In deriving these results, we review, develop and compare factorization techniques in conventional perturbative QCD and soft-collinear effective theory (SCET). We give special emphasis to the elimination of double counting of momentum regions in these two formalisms.

Authors:
 [1];  [2]
  1. Institute for Nuclear Theory, University of Washington, Seattle, Washington 98195-1550 (United States)
  2. C.N. Yang Institute for Theoretical Physics, Stony Brook University, Stony Brook, New York 11794-3840 (United States)
Publication Date:
OSTI Identifier:
20933236
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevD.75.014022; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CORRECTIONS; FACTORIZATION; GLUONS; PERTURBATION THEORY; QUANTUM CHROMODYNAMICS

Citation Formats

Lee, Christopher, and Sterman, George. Momentum flow correlations from event shapes: Factorized soft gluons and soft-collinear effective theory. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.014022.
Lee, Christopher, & Sterman, George. Momentum flow correlations from event shapes: Factorized soft gluons and soft-collinear effective theory. United States. doi:10.1103/PHYSREVD.75.014022.
Lee, Christopher, and Sterman, George. Mon . "Momentum flow correlations from event shapes: Factorized soft gluons and soft-collinear effective theory". United States. doi:10.1103/PHYSREVD.75.014022.
@article{osti_20933236,
title = {Momentum flow correlations from event shapes: Factorized soft gluons and soft-collinear effective theory},
author = {Lee, Christopher and Sterman, George},
abstractNote = {The distributions of two-jet event shapes contain information on hadronization in QCD. Near the two-jet limit, these distributions can be described by convolutions of nonperturbative event shape functions with the same distributions calculated in resummed perturbation theory. The shape functions, in turn, are determined by correlations of momentum flow operators with each other and with lightlike Wilson lines, which describe the coupling of soft, wide-angle radiation to jets. We observe that leading power corrections to the mean values of event shapes are determined by the correlation of a single momentum flow operator with the relevant Wilson lines. This generalizes arguments for the universality of leading power corrections based on the low-scale behavior of the running coupling or resummation. We also show how a study of the angularity event shapes can provide information on correlations involving multiple momentum flow operators, giving a window to the system of QCD dynamics that underlies the variety of event shape functions. In deriving these results, we review, develop and compare factorization techniques in conventional perturbative QCD and soft-collinear effective theory (SCET). We give special emphasis to the elimination of double counting of momentum regions in these two formalisms.},
doi = {10.1103/PHYSREVD.75.014022},
journal = {Physical Review. D, Particles Fields},
number = 1,
volume = 75,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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