{"paper":{"title":"The effects of a family non-universal Z-prime boson on B--->pipi decays","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["hep-ex"],"primary_cat":"hep-ph","authors_text":"Qin Chang, Xin-Qiang Li, Ya-Dong Yang","submitted_at":"2010-03-31T13:43:35Z","abstract_excerpt":"Motivated by the measured large branching ratio of $\\bar{B}^{0}\\to\\pi^0\\pi^0$ (the so-called \"$\\pi\\pi$\" puzzle), we investigate the effects of a family non-universal $Z^{\\prime}$ model on the tree-dominated $B\\to\\pi\\pi$ decays. We find that the $Z^{\\prime}$ coupling parameter $\\zeta_{d}^{LR}\\sim0.05$ with a nontrivial new weak phase $\\phi_d^L\\sim-50^{\\circ}$, which is relevant to the $Z^{\\prime}$ contributions to the QCD penguin sector $\\triangle C_5$, is needed to reconcile the observed discrepancy. Combined with the recent fitting results from $B\\to\\pi K$, $\\pi K^{\\ast}$ and $\\rho K$ decays,"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1003.6051","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":""},"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"}