2007/10/31 by The Belle Collaboration, A. Kusaka, I. Adachi +97 · 2 citations
Physics and Astronomy · #Black Holes and Theoretical Physics #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ex
paper · pdf · doi:10.1103/physrevd.77.072001
published as Phys.Rev.D77:072001,2008 · 26 pages, 12 figures, to be submitted to Phys. Rev. D; Revision to Phys. Rev. D published version
openalex publication_date 2008/04/03 · arxiv created 2008/04/28 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We present the results of a time-dependent Dalitz plot analysis of B0\ensuremath→\ensuremathπ+\ensuremathπ^\ensuremath-\ensuremathπ0 decays based on a 414 fb^\ensuremath-1 data sample that contains 449\ifmmode×\else\texttimes\fi106BB pairs. The data were collected on the \ensuremathΥ(4S) resonance with the Belle detector at the KEKB asymmetric energy e+e^\ensuremath- collider. Combining our analysis with information on charged B decay modes, we perform a full Dalitz and isospin analysis and obtain a constraint on the quark mixing angle \ensuremathφ2, 68\ifmmode^∘\else\textdegree\fi<\ensuremathφ2<95\ifmmode^∘\else\textdegree\fi at the 68.3% confidence level for the \ensuremathφ2 solution consistent with the standard model. A large standard-model--disfavored region also remains. The branching fractions for the decay processes B0\ensuremath→\ensuremathρ^\ifmmode±\else\textpm\fi(770)\ensuremathπ^\ensuremath∓ and B0\ensuremath→\ensuremathρ0(770)\ensuremathπ0 are measured to be (22.6\ifmmode±\else\textpm\fi1.1[stat]\ifmmode±\else\textpm\fi4.4[syst])\ifmmode×\else\texttimes\fi10^\ensuremath-6 and (3.0\ifmmode±\else\textpm\fi0.5[stat]\ifmmode±\else\textpm\fi0.7[syst])\ifmmode×\else\texttimes\fi10^\ensuremath-6, respectively. These are the first branching fraction measurements of the process B0\ensuremath→\ensuremathρ(770)\ensuremathπ with the lowest resonance \ensuremathρ(770) explicitly separated from the radial excitations.