{"paper":{"title":"Role of electromagnetic corrections in the $\\pi\\pi$ distributions of $\\psi^\\prime \\to J/\\psi \\pi \\pi$","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"Gang Li, Zhao-Sai Jia, Zhen-Hua Zhang","submitted_at":"2026-03-31T03:25:00Z","abstract_excerpt":"The cusp structure at the $\\pi^+\\pi^-$ threshold in the $\\pi^0\\pi^0$ invariant mass spectrum serves as a sensitive probe for extracting the $S$-wave $\\pi\\pi$ scattering lengths in processes where an $S$-wave $\\pi^0\\pi^0$ pair is produced in the final states. Within the framework of nonrelativistic effective field theory with coupled channels $\\pi^0\\pi^0$ and $\\pi^+\\pi^-$, we revisit the near-threshold structures in the $\\pi^0\\pi^0$ spectrum of $\\psi^\\prime \\to J/\\psi \\pi\\pi$. Our analysis incorporates the $\\pi \\pi$ final-state rescattering, including both strong and Coulomb interactions. It tu"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2603.29208","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2603.29208/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"}