{"paper":{"title":"Probing New Physics with $\\bar B \\to \\rho(770) \\, \\ell^- \\bar \\nu_\\ell$ and $\\bar B \\to a_1(1260) \\, \\ell^- \\bar \\nu_\\ell$","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["hep-ex","hep-lat"],"primary_cat":"hep-ph","authors_text":"F. De Fazio, F. Loparco, P. Colangelo","submitted_at":"2019-06-17T14:51:23Z","abstract_excerpt":"The $B$ meson semileptonic modes to $\\rho(770)$ and $a_1 (1260)$ are useful to pin down possible non Standard Model effects. The 4d differential $\\bar B \\to \\rho(\\pi \\pi) \\ell^- \\bar \\nu_\\ell$ and $ \\bar B \\to a_1 (\\rho \\pi) \\ell^- \\bar \\nu_\\ell$ decay distributions are computed in SM and in extensions involving new Lepton Flavour Universality violating semileptonic $b \\to u$ operators. The Large Energy limit for the light meson is also considered for both modes. The new effective couplings are constrained using the available data, and several observables in $\\bar B \\to \\rho(\\pi\\pi) \\ell^- \\ba"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1906.07068","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/1906.07068/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"}