{"paper":{"title":"A note on isospin violation in Pl2(gamma) decays","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"Helmut Neufeld, Vincenzo Cirigliano","submitted_at":"2011-02-02T21:01:04Z","abstract_excerpt":"We discuss the size of isospin violating effects of both electromagnetic (e \\neq 0) and strong (m_u \\neq m_d) origin in P_{\\ell 2 (\\gamma)} decays. Our results are relevant for the extraction of |V_{us}/V_{ud}| from the measured ratio of the K_{\\mu 2 (\\gamma)} and \\pi_{\\mu 2 (\\gamma)} decay widths combined with F_K/F_\\pi obtained in lattice calculations in the isospin limit. We point out that strong isospin-breaking corrections, neglected in previous studies, enter at the same level as the electromagnetic effects. The updated value for the ratio of CKM elements reads |V_{us}/V_{ud}| = 0.2316(1"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1102.0563","kind":"arxiv","version":1},"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"}