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Indirect Measurement of the Vertex and Angles of the Unitarity Triangle

Salvatore Mele
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Abstract

The precise measurements of the Bd oscillation frequency and the limit on the Bs one one as well as the determination of the Cabibbo-Kobayashi-Maskawa matrix element Vub improve the constraints on the other elements of this matrix. A fit to the experimental data and the theory calculations leads to the determination of the vertex of the unitarity triangle as: rho = 0.160 -0.070 +0.094 eta = 0.381 -0.058 +0.061. The values of its angles, in their customary definition in terms of sines for alpha and beta, are found to be: sin(2 alpha) = 0.06 -0.42 +0.35 sin(2 beta) = 0.75 +/- 0.09 gamma = 68 -12+11o. Indirect information on non-perturbative QCD parameters, on the presence of a CP violating complex phase in the CKM matrix and on the Bs oscillation frequency are also extracted.

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Salvatore Mele. 1998-10-13. Indirect Measurement of the Vertex and Angles of the Unitarity Triangle. https://doi.org/10.1103/physrevd.59.113011

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