2008/09/30 by M. Fujikawa, Y. Yusa, J. Dalseno +95
Chemistry · Engineering · Physics and Astronomy · #Analytical Chemistry (journal) #CP violation #Chemistry #Collider #Electron–positron annihilation #Hadron #KEKB #Nuclear physics #Particle Accelerators and Free-Electron Lasers #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #hep-ex
paper · pdf · doi:10.1103/physrevd.81.011101
published as Phys.Rev.D81:011101,2010 · 6 pages, 3 figures
arxiv created 2009/09/04 · openalex publication_date 2010/01/22 · openalex created_date 2016/06/24 · arxiv updated 2019/08/13 · openalex updated_date 2026/08/05
We report measurements of CP violation parameters in B0\ensuremath→K0\ensuremathπ0 decays based on a data sample of 657\ifmmode×\else\texttimes\fi106BB pairs collected with the Belle detector at the KEKB e+e^\ensuremath- asymmetric-energy collider. We use B0\ensuremath→KS0\ensuremathπ0 decays for both mixing-induced and direct CP violating asymmetry measurements and B0\ensuremath→KL0\ensuremathπ0 decays for the direct CP violation measurement. The CP violation parameters obtained are sin2\ensuremathφ1eff=+0.67\ifmmode±\else\textpm\fi0.31(stat)\ifmmode±\else\textpm\fi0.08(syst) and A_K0\ensuremathπ0=+0.14\ifmmode±\else\textpm\fi0.13(stat)\ifmmode±\else\textpm\fi0.06(syst). The branching fraction of B0\ensuremath→K0\ensuremathπ0 decay is measured to be B(B0\ensuremath→K0\ensuremathπ0)=(8.7\ifmmode±\else\textpm\fi0.5(stat.)\ifmmode±\else\textpm\fi0.6(syst.))\ifmmode×\else\texttimes\fi10^\ensuremath-6. The observed A_K0\ensuremathπ0 value differs by 1.9 standard deviations from the value expected from an isospin sum rule.