{"paper":{"title":"G-parity breaking in $\\tau^- \\to \\eta^{(\\prime)} \\pi^- \\nu_{\\tau}$ decays induced by the $\\eta^{(\\prime)}\\gamma\\gamma$ form factor","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"G. Hern\\'andez-Tom\\'e, G. L\\'opez Castro, P. Roig","submitted_at":"2017-07-10T19:53:39Z","abstract_excerpt":"Breaking of G-parity or new weak (second class) currents can be responsible for $\\tau^- \\to \\eta^{(\\prime)} \\pi^- \\nu_{\\tau}$ decays. Forthcoming measurements of $\\tau$ lepton properties at the Belle II experiment will be able to measure this decay channel for the first time. Isolating new physics contributions from the measured rates will require a careful evaluation of G-parity breaking contributions. Here we evaluate the one-loop contribution to $\\tau^- \\to \\eta^{(\\prime)} \\pi^- \\nu_{\\tau}$ decays induced by the emission of two virtual photons and its later conversion into an $\\eta^{(\\prime"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1707.03037","kind":"arxiv","version":2},"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"}