2006/08/31 by The Belle Collaboration, K. -F. Chen, K. Hara +95 · 5 citations
Physics and Astronomy · #Neutrino Physics Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ex
paper · pdf · doi:10.1103/physrevlett.98.031802
published as Phys.Rev.Lett.98:031802,2007 · 6 pages, 3 figures, updated to be consistent with the version published in PRL
openalex publication_date 2007/01/16 · arxiv created 2007/01/17 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We present improved measurements of CP-violation parameters in B0\ensuremath→\ensuremathφK0, \ensuremathη^\ensuremath'K0, KS0KS0KS0 decays based on a sample of 535\ifmmode×\else\texttimes\fi106 BB pairs collected at the \ensuremathΥ(4S) resonance with the Belle detector at the KEKB energy-asymmetric e+e^\ensuremath- collider. We obtain sin2\ensuremathφ1eff=+0.64\ifmmode±\else\textpm\fi0.10(stat)\ifmmode±\else\textpm\fi0.04(syst) for B0\ensuremath→\ensuremathη^\ensuremath'K0, +0.50\ifmmode±\else\textpm\fi0.21(stat)\ifmmode±\else\textpm\fi0.06(syst) for B0\ensuremath→\ensuremathφK0, and +0.30\ifmmode±\else\textpm\fi0.32(stat)\ifmmode±\else\textpm\fi0.08(syst) for B0\ensuremath→KS0KS0KS0 decays. We have observed CP violation in the B0\ensuremath→\ensuremathη^\ensuremath'K0 decay with a significance of 5.6 standard deviations. We also perform an improved measurement of CP asymmetries in B0\ensuremath→J/\ensuremathψK0 decays and obtain sin2\ensuremathφ1=+0.642\ifmmode±\else\textpm\fi0.031(stat)\ifmmode±\else\textpm\fi0.017(syst).