{"paper":{"title":"Chiral anomaly in the $\\eta^{(\\prime)}\\to\\pi^+\\pi^-\\gamma$ and $\\eta^{(\\prime)}\\to\\pi^+\\pi^-l^+l^-$ decays","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"A. A. Osipov, A. A. Pivovarov, K. Nurlan, M. K. Volkov","submitted_at":"2026-01-11T15:35:06Z","abstract_excerpt":"We report the presence of a flavor-violating correction to the $VAAA$-type anomaly, $\\delta^{(\\prime)}$, induced by the surface terms of the anomalous quark triangle diagram, previously found in the $\\eta,\\eta'\\to\\pi^+\\pi^-\\gamma$ decay amplitudes, and investigate its impact on the corresponding semileptonic decay modes of $\\eta$ and $\\eta'$. The magnitude of $\\delta^{(\\prime)}$ can be set from the experimental data on the $\\eta^{(\\prime)}\\to \\pi^+\\pi^-\\gamma$ decay width. We then estimate another low-energy constant, the slope parameter $\\alpha^{(\\prime)}$. The impact of different schemes for"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2601.06958","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2601.06958/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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"}