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CP Asymmetry A_{ψK_S}, \sin 2β, the Sign of ΔM_B and the Physics Beyond the Standard Model

Monika Blanke·Andrzej J. Buras
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Abstract

We demonstrate that the sign of the B^0-\bar B^0 mass difference ΔM_B is irrelevant for the extraction of the angle β=ϕ_1 of the unitarity triangle from the CP asymmetry A_{ψK_S}. Only the weak phase in the mixing amplitude M_{12} matters. Consequently the extraction of \sin 2βdone by BaBar and Belle can only be affected by new weak phases in M_{12} in the extensions of the SM and possibly but unlikely by new physics contributions to the decay amplitude.

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Monika Blanke, Andrzej J. Buras. 2004-12-22. CP Asymmetry A_{ψK_S}, \sin 2β, the Sign of ΔM_B and the Physics Beyond the Standard Model. https://arxiv.org/abs/hep-ph/0412195

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