{"paper":{"title":"Observation of B^0 \\to D^{*-} \\tau^+ \\nu_{\\tau} decay at Belle","license":"","headline":"","cross_cats":[],"primary_cat":"hep-ex","authors_text":"A. Matyja, et al (for the Belle Collaboration), M. Rozanska","submitted_at":"2007-06-29T14:27:28Z","abstract_excerpt":"We report an observation of the decay $B^0\\to D^{*-} \\tau^+ \\nu_{\\tau}$ in a data sample containing $535\\times10^6$ $B\\bar{B}$ pairs collected with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. We find a signal with a significance of 5.2 standard deviations and measure the branching fraction $\\mathcal{B}(B^0\\to D^{*-} \\tau ^+ \\nu_{\\tau})=(2.02 ^{+0.40}_{-0.37} (stat) \\pm 0.37 (syst)) % $. This is the first observation of an exclusive $B$ decay with a $b \\to c \\tau \\nu_{\\tau}$ transition."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0706.4429","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/0706.4429/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"}