ISOSPIN AMPLITUDE ANALYSIS OF B → ππ DECAYS WITHIN THE STANDARD MODEL

摘要

Taking into account the recent measurements of the branching ratios and CP asymmetries in the B → ππ decays by the BABAR and BELLE collaborations, an amplitude analysis based on the isospin symmetry is reported. These data allow to get an independent determination of the CKM unitarity-triangle angle γ. One of the best-fit solutions gives the range γ = (65 ± 5)°, in excellent agreement with the global CKM fit within the Standard Model. The other parameters from this fit confirm the earlier analyses that the data on B → ππ decays require various topological amplitudes (neglecting the electroweak ones) to be of comparable magnitude with large strong-phase differences.