Light-cone divergence in twist-3 correlation functions
Abstract
It is argued that the definition of the twist-3 transverse momentum dependent correlation functions must be modified if they contain light-like Wilson lines. In the framework of a simple spectator model of the nucleon we show explicitly the presence of a light-cone divergence for a specific twist-3 time-reversal odd parton density. This divergence emerges for all eight twist-3 T-odd correlators and appears also in the case of a quark target in perturbative QCD. The divergence can be removed by using non-light-like Wilson lines. Based on our results we argue that currently there exists no established factorization formula for transverse momentum dependent twist-3 observables in semi-inclusive DIS and related processes.
Cite
@article{arxiv.hep-ph/0604022,
title = {Light-cone divergence in twist-3 correlation functions},
author = {L. P. Gamberg and D. S. Hwang and A. Metz and M. Schlegel},
journal= {arXiv preprint arXiv:hep-ph/0604022},
year = {2008}
}
Comments
6 pages, 1 figure, slightly extended version, to appear in Phys. Lett. B