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We report a measurement of the branching fraction of $B^+ to tau^+ u_tau$ decays using a data sample of $772 times 10^6 B bar{B}$ pairs, collected at the $Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider . We reconstruct the accompanying $B$ meson in a semileptonic decay and detect the $B^+ to tau^+ u_tau$ candidate in the recoiling event. We obtain a branching fraction of ${cal B}(B^+ to tau^+ u_tau) = [1.25 pm 0.28 ({rm stat.}) pm 0.27({rm syst.})] times 10^{-4}$. This result is in good agreement with previous measurements and the expectation from calculations based on the Standard Model.
We report the measurement of the branching fraction, the polarization, and the parameters of the time-dependent CP violation in B0 -> D*+ D*- decays using a data sample of 772 million BB pairs, collected at the Y(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We obtain a branching fraction of B = (7.82 +- 0.38 +- 0.63) x10^{-4}, a CP-odd fraction of R_perp = 0.138 +- 0.024 +- 0.006 and, additionally, a fraction of the longitudinal component in the transversity base of R_0 = 0.624 +- 0.029 +- 0.011. The measured values of the parameters of the CP violation are S_{D*+ D*-} = -0.79 +- 0.13 +- 0.03 and A_{D*+ D*-} = 0.15 +- 0.08 +- 0.04.
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