{"paper":{"title":"The puzzle of anomalously large isospin violations in $\\eta(1405/1475)\\to 3\\pi$","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["hep-ex","nucl-ex","nucl-th"],"primary_cat":"hep-ph","authors_text":"Bing-Song Zou, Jia-Jun Wu, Qiang Zhao, Xiao-Hai Liu","submitted_at":"2011-08-18T14:53:46Z","abstract_excerpt":"The BES-III Collaboration recently report the observation of anomalously large isospin violations in $J/\\psi\\to \\gamma\\eta(1405/1475) \\to \\gamma \\pi^0 f_0(980)\\to \\gamma +3\\pi$, where the $f_0(980)$ in the $\\pi\\pi$ invariant mass spectrum appears to be much narrower ($\\sim$ 10 MeV) than the peak width ($\\sim$50 MeV) measured in other processes. We show that a mechanism, named as triangle singularity (TS), can produce a narrow enhancement between the charged and neutral $K\\bar{K}$ thresholds, i.e., $2m_{K^\\pm}\\sim 2m_{K^0}$. It can also lead to different invariant mass spectra for $\\eta(1405/14"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1108.3772","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"}