Angles of the CKM Unitarity Triangle Measured at Belle
| dc.creator | Schwartz, A. J. | |
| dc.date | 2005-08-15 | |
| dc.date.accessioned | 2026-07-07T03:37:03Z | |
| dc.date.available | 2026-07-07T03:37:03Z | |
| dc.description | The Belle experiment has used several methods to measure or constrain the angles phi_1, phi_2, and phi_3 (or beta, alpha, and gamma) of the CKM unitarity triangle. The results are sin(2phi_1) = 0.728 \pm 0.056 (stat) \pm 0.023 (syst) or phi_1= (23.4 +2.7 -2.4) degrees from B0 -> J/psi K0 decays (140 fb-1); phi_2 = 0-19 degrees or 71-180 degrees at 95.4% CL from B0 -> pi+pi- decays (253 fb-1); and phi_3 = [68 +14 -15 (stat) \pm 13 (syst) \pm 11 (model)] degrees from B+ -> (D0, D0bar) K+, (D0,D0bar) -> K0_S pi+ pi- decays (253 fb-1). These values satisfy the triangle relation phi_1 + phi_2 + phi_3 = 180 degrees within their uncertainties. The angle phi_1 is also determined from several b -> s qbar q penguin-dominated decay modes; the value obtained by taking a weighted average of the individual results differs from the B0 -> J/psi K0 result by more than two standard deviations. The angle phi_2 is constrained by measuring a CP asymmetry in the decay time distribution; the asymmetry observed is large, and the difference in the yields of B0,B0bar -> pi+ pi- decays constitutes the first evidence for direct CP violation in the B system. | |
| dc.description | 14 pages, 6 figures, 2 tables, recent results from the Belle experiment. Contribution to the 19th Les Rencontres de Physique de la Vallee d'Aoste | |
| dc.identifier | https://arxiv.org/abs/hep-ex/0508033 | |
| dc.identifier | http://arxiv.org/abs/hep-ex/0508033 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/37959 | |
| dc.subject | High Energy Physics - Experiment | |
| dc.title | Angles of the CKM Unitarity Triangle Measured at Belle | |
| dc.type | text |