{"paper":{"title":"On the Role of Charmed Meson Loops in Charmonium Decays","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"Di-Lun Yang, Thomas Mehen","submitted_at":"2011-11-16T17:46:08Z","abstract_excerpt":"We investigate the effect of intermediate charmed meson loops on the M1 radiative decays $J/\\psi \\to \\eta_c \\gamma$ and $\\psi'\\rightarrow\\eta^{(\\prime)}_c\\gamma$ as well as the isospin violating hadronic decays $\\psi'\\rightarrow J/\\psi \\,\\pi^0(\\eta)$ using heavy hadron chiral perturbation theory (HH$\\chi$PT). The calculations include tree level as well as one loop diagrams and are compared to the latest data from CLEO and BES-III. Our fit constrains the couplings of 1S and 2S charmonium multiplets to charmed mesons, denoted $g_2$ and $g_2^\\prime$, respectively. We find that there are two sets "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1111.3884","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"}