{"paper":{"title":"Measurements of branching fractions and $q^2$ distributions for $B \\to \\pi \\ell \\nu$ and $B \\to \\rho \\ell \\nu$ Decays with $B \\to D^{(*)} \\ell \\nu$ Decay Tagging","license":"","headline":"","cross_cats":[],"primary_cat":"hep-ex","authors_text":"T. Hokuue (for the Belle Collaboration)","submitted_at":"2006-04-12T06:06:35Z","abstract_excerpt":"We report measurements of the charmless semileptonic decays $B^0 \\to \\pi^- / \\rho^- \\ell^{+} \\nu$ and $B^+ \\to \\pi^0 / \\rho^0 \\ell^{+} \\nu$, based on a sample of $2.75 \\times 10^8$ $B \\bar{B}$ events collected at the $\\Upsilon(4S)$ resonance with the Belle detector at the KEKB $e^+e^-$ asymmetric collider. In this analysis, the accompanying $B$ meson is reconstructed in the semileptonic mode $B \\to D^{(*)} \\ell \\nu$, enabling detection of the signal modes with high purity. We measure the branching fractions ${\\mathcal B}(B^0 \\to \\pi^- \\ell^+ \\nu) = (1.38\\pm 0.19\\pm 0.14\\pm 0.03) \\times 10^{-4}"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ex/0604024","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/hep-ex/0604024/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"}