Publication
Title
Wilson lines in transverse-momentum dependent parton distribution functions with spin degrees of freedom
Author
Abstract
We propose a new framework for transverse-momentum dependent parton distribution functions, based on a generalized conception of gauge invariance which includes into the Wilson lines the Pauli term similar to F(mu nu)[gamma(mu), gamma(nu)]. We discuss the relevance of this nonminimal term for unintegrated parton distribution functions, pertaining to spinning particles, and analyze its influence on their renormalization-group properties. It is shown that while the Pauli term preserves the probabilistic interpretation of twist-two distributions-unpolarized and polarized-it gives rise to additional pole contributions to those of twist-three. The anomalous dimension induced this way is a matrix, calling for a careful analysis of evolution effects. Moreover, it turns out that the crosstalk between the Pauli term and the longitudinal and the transverse parts of the gauge fields, accompanying the fermions, induces a constant, but process-dependent, phase which is the same for leading and subleading distribution functions. We include Feynman rules for the calculation with gauge links containing the Pauli term and comment on the phenomenological implications of our approach. (C) 2010 Elsevier B.V. All rights reserved.
Language
English
Source (journal)
Nuclear physics: B. - Amsterdam
Publication
Amsterdam : 2010
ISSN
0550-3213
0029-5582
Volume/pages
840:1-2(2010), p. 379-404
ISI
000281832900014
Full text (Publisher's DOI)
Full text (open access)
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Faculty/Department
Research group
Publication type
Subject
External links
Web of Science
Record
Identification
Creation 06.01.2015
Last edited 11.07.2017