sin2phi_2(alpha)) from Belle

Eunil Won

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arXiv · hep-ex/0206066

sin2phi_2(alpha)) from Belle

Eunil Won

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Abstract

We present a measurement of CP-violating asymmetries in B0 -> pi+pi- decays based on 41.8 fb-1 data sample collected at the Y(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. From the asymmetry in the distribution of the time intervals between the two B meson decay points, we obtain the CP-violating asymmetry parameters S_pipi = -1.21 + 0.38 - 0.27 (stat) + 0.16 - 0.13 (syst) and A_pipi = +0.94 + 0.25 - 0.31 (stat) +- 0.09 (syst).

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Eunil Won. 2002-06-26. sin2phi_2(alpha)) from Belle. https://arxiv.org/abs/hep-ex/0206066

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