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Towards a Precision Determination of alpha in B \to pi pi Decays

Susan Gardner
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Abstract

An assumption of isospin symmetry permits the determination of sin(2 alpha) from the experimental study of B\to pi pi decays. Isospin, however, is merely an approximate symmetry; its breaking predicates a theoretical systematical error sigma_α^{\rm IB} in the extraction of alpha. We focus on the impact of π^0-η,η^\prime mixing, as well as the manner in which it is amenable to empirical constraint, and determine that σ_α^{\rm IB} can potentially be controlled to {\cal O}(1^\circ).

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Susan Gardner. 2005-05-17. Towards a Precision Determination of alpha in B \to pi pi Decays. https://doi.org/10.1103/physrevd.72.034015

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