{"paper":{"title":"Measurement of the branching fraction, polarization, and CP asymmetry in B0 -> rho+rho- decays","license":"","headline":"","cross_cats":[],"primary_cat":"hep-ex","authors_text":"et al. (for the Belle Collaboration), K. Abe","submitted_at":"2005-07-09T03:51:48Z","abstract_excerpt":"We have measured the branching fraction, longitudinal polarization fraction f_L, and the CP asymmetry coefficients A and S in B0 -> rho+rho- decays. These results are obtained from a 253 fb-1 data sample containing 275 million B\\bar{B} pairs collected by the Belle detector running at the KEKB e+e- collider. We obtain B = [24.4 \\pm 2.2 (stat) +3.8 -4.1 (syst)] x 10-6, f_L = 0.951 +0.033 -0.039 (stat) +0.029 -0.031 (syst), A = 0.00 \\pm 0.30 (stat) +0.10 -0.09 (syst), and S = 0.09 \\pm 0.42 (stat) \\pm 0.08 (syst). These values are used to determine the CKM phase angle phi_2 (alpha) via an isospin "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ex/0507039","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/hep-ex/0507039/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"}