Sivers function in a spectator model with axial-vector diquarks
High Energy Physics - Phenomenology
2015-06-25 v3
Abstract
We perform a calculation of the Sivers function in a spectator model of the nucleon, with scalar and axial-vector diquarks. We make use of gluon rescattering to produce the nontrivial phases necessary to generate the Sivers function. The inclusion of axial-vector diquarks enables us to obtain a nonzero Sivers function for down quarks. Using the results of our model, we discuss the phenomenology of transvere single spin asymmetries in pi+, pi-, and pi0 production, which are currently analysed by the HERMES and COMPASS collaborations. We find that the inclusion of axial-vector diquarks substantially reduces the asymmetries.
Cite
@article{arxiv.hep-ph/0309246,
title = {Sivers function in a spectator model with axial-vector diquarks},
author = {Alessandro Bacchetta and Andreas Schaefer and Jian-Jun Yang},
journal= {arXiv preprint arXiv:hep-ph/0309246},
year = {2015}
}
Comments
8 pages, 7 figures, uses RevTex, added calculation of h1^perp, final version accepted for publication in PLB