{"paper":{"title":"Observation of excess J/$\\psi$ yield at very low transverse momenta in Au+Au collisions at $\\sqrt{s_{\\rm{NN}}} =$ 200 GeV and U+U collisions at $\\sqrt{s_{\\rm{NN}}} =$ 193 GeV","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"hep-ex","authors_text":"STAR Collaboration","submitted_at":"2019-04-26T02:49:29Z","abstract_excerpt":"We report on the first measurements of J/$\\psi$ production at very low transverse momentum ($p_{T} <$ 0.2 GeV/c) in hadronic Au+Au collisions at $\\sqrt{s_{\\rm{NN}}} =$ 200 GeV and U+U collisions at $\\sqrt{s_{\\rm{NN}}} =$ 193 GeV. Remarkably, the inferred nuclear modification factor of J/$\\psi$ at mid-rapidity in Au+Au (U+U) collisions reaches about 24 (52) for $p_{T} <$ 0.05 GeV/c in the 60-80$\\%$ collision centrality class. This noteworthy enhancement cannot be explained by hadronic production accompanied by cold and hot medium effects. In addition, the $dN/dt$ distribution of J/$\\psi$ for th"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1904.11658","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/1904.11658/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"}