Extraction of α From the CP Asymmetry in B 0 / B̄ 0 → π + π −
نویسنده
چکیده
The influence of strong and electroweak penguin amplitudes in B/B̄ → ππ is investigated in connection with the determination of the unitarity triangle angle α of the CKM matrix. A relation between the observable asymmetry, the angle α, and the penguin amplitude is established. A model calculation of the penguin amplitude shows that the CP asymmetry in B → ππ decays is only mildly influenced by the penguin amplitudes. Experimental limits on pure penguin and penguin dominated processes are consistent with the model. This information also suggests in a rather model independent way that penguin amplitudes will not be a serious complicating factor in the determination of α from the ππ time dependent asymmetry. Supported by Bundesministerium für Forschung und Technologie, 05 6HH93P(5), Bonn, Germany and EEC Program “Human Capital and Mobility” Network “Physics at High Energy Colliders” CHRX-CT93-0357 (DG 12 COMA) Supported in part by the US Department of Energy under contract DOE/ER/01545-605.
منابع مشابه
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