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A New Method for Determining gamma from B-> pi pi Decays

Christian W. Bauer·Ira Z. Rothstein·Iain W. Stewart
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Abstract

Factorization based on the soft-collinear effective theory (SCET) can be used to reduce the number of hadronic parameters in an isospin analysis of B-> pi pi decays by one. This gives a theoretically precise method for determining the CP violating phase gamma by fitting to the B-> pi pi data without C_{pi0 pi0}. SCET predicts that gamma lies close to the isospin bounds. With the current world averages we find gamma=75^o \pm 2^o {}^{+9^o}_{-13^o}, where the uncertainties are theoretical, then experimental.

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Christian W. Bauer, Ira Z. Rothstein, Iain W. Stewart. 2005-05-10. A New Method for Determining gamma from B-> pi pi Decays. https://doi.org/10.1103/physrevlett.94.231802

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