{"paper":{"title":"$|V_{cb}|$ from OPE Sum Rules for Heavy Flavor Transitions","license":"","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"A. Vainshtein, M. Shifman, N.G. Uraltsev","submitted_at":"1994-05-03T06:07:33Z","abstract_excerpt":"We derive a model-independent upper bound for the axial-vector form factor of the $B\\ra D^*$ transition at zero recoil, $F_{B\\ra D^*}$. The form factor turns out to be noticeably less than unity. The deviation of $F_{B\\ra D^*}$ from unity is larger than previously anticipated. Using our estimate we extract $|V_{cb}|$ from the measured exclusive rate of $B\\ra D^* l\\nu$ extrapolated to the point of zero recoil. The central `` exclusive\" value of $|V_{cb}|$ is in agreement with the value obtained from the inclusive semileptonic width $\\Gamma (B\\ra X_c l\\nu)$. We argue that the theoretical uncerta"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/9405207","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"}