On the gauge invariance of the DVCS amplitude
High Energy Physics - Phenomenology
2009-12-30 v2
Abstract
We analyze in detail the problem of gauge invariance of the deeply vitual Compton scattering (DVCS) amplitude. Using twist 3 one-gluon exchange diagram contributions and the QCD equations of motion, we derive the general gauge invariant expression of the DVCS amplitude on a (pseudo)scalar particle (pion, ). Similarly to the case of deep inelastic scattering, the amplitude does not depend on the twist-3 quark-gluon correlations at the Born level. The contribution of the derived amplitude to the single-spin asymmetry with longitudinally polarized lepton is calculated.
Cite
@article{arxiv.hep-ph/0003203,
title = {On the gauge invariance of the DVCS amplitude},
author = {I. V. Anikin and B. Pire and O. V. Teryaev},
journal= {arXiv preprint arXiv:hep-ph/0003203},
year = {2009}
}
Comments
5 pages, 1 figure, LaTeX; Types fixed, formula for asymmetry completed, one reference added