4 v 1 3 1 D ec 2 00 6 Penguin pollution estimates relevant for φ 2 / α extraction
نویسنده
چکیده
with the ultimate theory error below percent level [2]. This sets high standards for the determinations of the other two angles, α = arg(−V ∗ tbVtd/V ∗ ubVud) and γ = arg(−V ∗ ubVud/V ∗ cbVcd). In this review we address the theoretical errors for the methods that are used in the determination of α. They represent the ultimate precision at which the angle α can be measured even with unlimited statistics. The theoretical uncertainties arise because sin 2α is directly related to measured CP asymmetries only in the limit of one dominant amplitude. Focusing for the moment on B → ππ decays for clarity, we define the ”tree”, T , and ”penguin”, P , amplitudes
منابع مشابه
ar X iv : h ep - p h / 07 01 00 4 v 2 1 6 A ug 2 00 7 Penguin pollution estimates relevant for φ 2 / α extraction
with the ultimate theory error below percent level [2]. This sets high standards for the determinations of the other two angles, α = arg(−V ∗ tbVtd/V ∗ ubVud) and γ = arg(−V ∗ ubVud/V ∗ cbVcd). In this review we address the theoretical errors for the methods that are used in the determination of α. They represent the ultimate precision at which the angle α can be measured even with unlimited st...
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