An enhancement for the η production in proton-neutron collisions as compared with that in proton-proton scattering has been recently observed. We present a calculation for the production cross section, in proton-neutron collisions near threshold, within instanton model for the QCD vacuum and show that a specific flavor dependent nonperturbative quark-gluon interaction related to instantons is able to explain the observed enhancement.
@article{arxiv.hep-ph/9905438,
title = {Instantons and $\eta$ Meson Production near threshold in NN collisions},
author = {N. I. Kochelev and V. Vento and A. V. Vinnikov},
journal= {arXiv preprint arXiv:hep-ph/9905438},
year = {2009}
}
Comments
11 pages, latex, 3 figures, revised version, footnotes have been added, the notation of two formulas slightly changed, and conclusions enlarged