{"paper":{"title":"Subleading shape functions in B -> X_u l \\nu and the determination of |Vub|","license":"","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"Christian W. Bauer, Michael Luke, Thomas Mannel","submitted_at":"2002-05-15T20:38:03Z","abstract_excerpt":"We calculate the subleading twist contributions to the endpoint of the inclusive lepton energy spectrum in B -> X_u l \\nu. We show that the same two subleading twist functions that appear in the decay B -> X_s \\gamma govern the subleading effects in this decay. Using these results we find large O(Lambda/mB) corrections to the determination of |Vub| from the endpoint of the charged lepton spectrum. Using a simple model for the relevant subleading shape functions, we estimate the uncertainty in |Vub| from Lambda/mb corrections to be at the ~ 15% level for a lower lepton energy cut of 2.2 GeV."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/0205150","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":""},"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"}