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arXiv · 1507.06671

Towards more precise determinations of the CKM phase $β$

Zoltan Ligeti·Dean J. Robinson
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Abstract

We derive a new flavor symmetry relation for the determination of the weak phase $β=ϕ_1$ from time-dependent CP asymmetries and $B \to J/ψP$ decay rates. In this relation, the contributions to $\sin2β$ proportional to $V_{ub}$ are parametrically suppressed compared to the contributions in the $B \to J/ψK^0$ time-dependent CP asymmetry alone. This relation uses only $SU(3)$ flavor symmetry, and does not require further diagrammatic assumptions. The current data either fluctuate at the $2σ$ level from expectations, or may hint at effects of unexpected magnitude from contributions proportional to $V_{ub}$ or from isospin breaking.

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Zoltan Ligeti, Dean J. Robinson. 2015-11-30. Towards more precise determinations of the CKM phase $β$. https://doi.org/10.1103/physrevlett.115.251801

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