{"paper":{"title":"Determination of the strong coupling $g_{B^* B\\pi}$ from semi-leptonic $B\\to \\pi \\ell \\nu$ decay","license":"http://creativecommons.org/licenses/by/3.0/","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"Fang Su, Xin-Qiang Li, Ya-Dong Yang","submitted_at":"2010-11-01T08:52:07Z","abstract_excerpt":"According to heavy-meson chiral perturbation theory, the vector form factor $f_+(q^2)$ of exclusive semi-leptonic decay $B\\to \\pi \\ell \\nu$ is closely related, at least in the soft-pion region (i.e., $q^{2} \\sim (m_B-m_{\\pi})^2$), to the strong coupling $g_{B^* B\\pi}$ or the normalized coupling $\\hat g$. Combining the precisely measured $q^2$ spectrum of $B\\to \\pi \\ell \\nu$ decay by the BaBar and Belle collaborations with several parametrizations of the form factor $f_+(q^2)$, we can extract these couplings from the residue of the form factor at the $B^*$ pole, which relies on an extrapolation"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1011.0269","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":""},"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"}