English

Gluon orbital angular momentum at small-$x$

High Energy Physics - Phenomenology 2017-07-05 v2 High Energy Physics - Experiment Nuclear Experiment Nuclear Theory

Abstract

We present a general analysis of the orbital angular momentum (OAM) distribution of gluons Lg(x)L_g(x) inside the nucleon with particular emphasis on the small-xx region. We derive a novel operator representation of Lg(x)L_g(x) in terms of Wilson lines and argue that it is approximately proportional to the gluon helicity distribution Lg(x)2ΔG(x)L_g(x) \approx -2\Delta G(x) at small-xx. We also compute longitudinal single spin asymmetry in exclusive diffractive dijet production in lepton-nucleon scattering in the next-to-eikonal approximation and show that the asymmetry is a direct probe of the gluon helicity/OAM distribution as well as the QCD odderon exchange.

Keywords

Cite

@article{arxiv.1612.02445,
  title  = {Gluon orbital angular momentum at small-$x$},
  author = {Yoshitaka Hatta and Yuya Nakagawa and Bowen Xiao and Feng Yuan and Yong Zhao},
  journal= {arXiv preprint arXiv:1612.02445},
  year   = {2017}
}

Comments

22 pages. v2 significantly expands the previous version with all the details of derivation as well as a number of new results and discussions. The title and abstract are changed, and an author is added

R2 v1 2026-06-22T17:16:52.523Z