Quark loop contribution to \pi^0 \to 4\gamma
High Energy Physics - Phenomenology
2013-05-29 v3
Abstract
We find the contribution of constituent quark loop mechanism to the branching ratio B_{4\gamma} = \Gamma_{4\gamma}/\Gamma_{4\gamma} \sim 5.45 \cdot 10^{-16} for the reasonable choice of constituent quark mass m \sim 280 MeV. This result is in agreement with vector-dominance approach result obtained years ago. Thus the main contribution arises from QED mechanism \pi^0 \to \gamma (\gamma^*) \to \gamma (3\gamma) including light-light scattering block with electron loop. This contribution was investigated in paper of one of us and gave B_{4\gamma} \sim 2.6 \cdot 10^{-11}.
Keywords
Cite
@article{arxiv.hep-ph/0311086,
title = {Quark loop contribution to \pi^0 \to 4\gamma},
author = {E. A. Kuraev and V. V. Bytev and Yu. M. Bystritskiy},
journal= {arXiv preprint arXiv:hep-ph/0311086},
year = {2013}
}
Comments
7 pages, 2 figures