{"paper":{"title":"Improved covariant analysis of $B_c^+ \\to \\chi_{c1}(nP)$ decays and implications for the nature of $\\chi_{c1}(3872)$","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"Chao-Hsi Chang, Guo-Li Wang, Jia-Yi Zheng, Shi-Hang Zhang, Su-Yan Pei, Tianhong Wang, Wei Li, Zhi-Hui Wang","submitted_at":"2026-08-05T11:00:21Z","abstract_excerpt":"We study the weak decays $B_c^+\\to\\chi_{c1}(nP)\\ell^+ \\nu_{\\ell}$ and $B_c^+\\to\\chi_{c1}(nP)X$ (n=1,2,3) within the Bethe-Salpeter formalism, treating $\\chi_{c1}(3872)$ as the conventional $\\chi_{c1}(2P)$ charmonium. We upgrade the covariant hadronic transition amplitude to consistently evaluate the final-state wave function in its rest frame, enabling a reliable description of large-recoil processes and sizable relativistic corrections pertinent to highly excited charmonium. Our results provide a novel platform to probe the internal structure of $\\chi_{c1}(3872)$ via $B_c$ decays. While the L"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2608.04693","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/2608.04693/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"}