{"paper":{"title":"Quark loop contribution to \\pi^0 \\to 4\\gamma","license":"","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"E. A. Kuraev, V. V. Bytev, Yu. M. Bystritskiy","submitted_at":"2003-11-06T17:56:12Z","abstract_excerpt":"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}."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/0311086","kind":"arxiv","version":3},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}