{"paper":{"title":"$R(J/\\psi)$ and $B_c^- \\rightarrow J/\\psi \\ell^-\\bar{\\nu}_\\ell$ Lepton Flavor Universality Violating Observables from Lattice QCD","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["hep-ph"],"primary_cat":"hep-lat","authors_text":"Andrew Lytle, Christine T. H. Davies, Judd Harrison","submitted_at":"2020-07-14T10:31:47Z","abstract_excerpt":"We use our lattice QCD computation of the $B_c\\rightarrow J/\\psi$ form factors to determine the differential decay rate for the semitauonic decay channel and construct the ratio of branching fractions $R(J/\\psi) = \\mathcal{B}(B_c^- \\rightarrow J/\\psi \\tau^-\\bar{\\nu}_\\tau)/\\mathcal{B}(B_c^- \\rightarrow J/\\psi \\mu^-\\bar{\\nu}_\\mu)$. We find $R(J/\\psi) = 0.2582(38)$ and give an error budget. We also extend the relevant angular observables, which were recently suggested for the study of lepton flavor universality violating effects in $B\\rightarrow D^*\\ell\\nu$, to $B_c \\rightarrow J/\\psi\\ell\\nu$ and"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2007.06956","kind":"arxiv","version":3},"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/2007.06956/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"}