{"paper":{"title":"Quarkonium chromo-polarizability from the decays $J/\\psi(\\Upsilon) \\to \\pi \\pi \\ell^+ \\ell^-$","license":"","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"M.B. Voloshin","submitted_at":"2004-02-02T16:43:57Z","abstract_excerpt":"It is pointed out that the diagonal amplitude of the $E1-E1$ chromo-electric interaction with soft gluon fields (chromo-polarizability) can be measured directly for the $J/\\psi$ and $\\Upsilon$ resonances in the decays $J/\\psi \\to \\pi \\pi \\ell^+ \\ell^-$ and $\\Upsilon \\to \\pi \\pi \\ell^+ \\ell^-$ with soft pions. For the $J/\\psi$ this amplitude is often discussed in connection with the $J/\\psi$ interaction with nuclear matter, while for the $\\Upsilon$ the chromo-polarizability enters the estimates of the non-perturbative mass shift of the resonance relevant to precision determination of the $b$ qu"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/0402011","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/hep-ph/0402011/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"}