Results for \phi_1 and \phi_2 from Belle

Abstract

We present a summary of measurements sensitive to the CKM angles \phi_1 and \phi_2, performed by the Belle experiment using the final data sample of 772 \times 10^{6} $B\bar{B}$ pairs at the \Upsilon(4S) resonance produced at the KEK asymmetric e^+e^- collider. We discuss CP asymmetries from the decays $B^0\to c\bar{c}{K}^0$, $D^{(\ast )+}{D}^{(\ast )-}$ which are sensitive to \phi_1 and from $B\to {\pi }^{+}{\pi }^{-}$, $a_1\pm {\pi }^{\mp }$ being sensitive to \phi_2. Furthermore the measurement of the branching fraction of $B^0\to {\rho }^0{\rho }^0$ decays and fraction of longitudinal polarization in this decay is presented and used to constrain \phi_2 with an isospin analysis in the $B\to \rho \rho$ system.

Comments: Proceedings of CKM2012, the 7th International Workshop on the CKM Unitarity Triangle, Cincinnati, USA, 6-10 September 2012