English

Instantons in Lepton Pair Production

High Energy Physics - Phenomenology 2009-11-11 v2 High Energy Physics - Experiment High Energy Physics - Theory

Abstract

We consider QCD instanton-induced contributions to lepton pair production in hadron-hadron collisions. We relate these contributions to those known from deep inelastic scattering and demonstrate that they can be calculated reliably for sufficiently large momentum transfer. We observe that the instanton contribution to the angular distribution of the lepton pairs at finite momentum transfer strongly violates the Lam-Tung relation - a relation between coefficient functions of the angular distribution which is valid within the framework of ordinary perturbation theory. The drastic violation of this relation, as seen in experimental data, might be related to such instanton-induced effects.

Keywords

Cite

@article{arxiv.hep-ph/0605234,
  title  = {Instantons in Lepton Pair Production},
  author = {A. Brandenburg and A. Ringwald and A. Utermann},
  journal= {arXiv preprint arXiv:hep-ph/0605234},
  year   = {2009}
}

Comments

24 pages, 9 figures, some comments added; to appear in Nuclear Physics B