English

No Landau-Yang in QCD

High Energy Physics - Phenomenology 2016-11-30 v3

Abstract

The Landau-Yang theorem, forbidding transition amplitudes between a massive spin-1 particle and two photons, is widely assumed to apply to other massless spin-1 particles. We show that this is not true in Standard-Model QCD, so that for instance antisymmetric colour-octet spin-1 quarkonia can be formed by two on-shell gluons in second-order perturbative QCD.

Keywords

Cite

@article{arxiv.1508.07115,
  title  = {No Landau-Yang in QCD},
  author = {W. Beenakker and R. Kleiss and G. Lustermans},
  journal= {arXiv preprint arXiv:1508.07115},
  year   = {2016}
}

Comments

4 pages, 3 figures

R2 v1 2026-06-22T10:43:31.293Z