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arXiv · hep-ph/9812384

Precise tests of a quark mass texture

Riccardo Barbieri·Lawrence J. Hall·Andrea Romanino
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Abstract

The relations $|V_{ub}/V_{cb}|=(m_u/m_c)^{1/2}$ and $|V_{td}/V_{ts}|=(m_d/m_s)^{1/2}$ between the CKM matrix elements and the quark masses are shown to imply a remarkably precise determination of the CKM unitarity triangle or of the Wolfenstein parameters $ρ$, $η$ consistent with the data so far. We view this as a clean test of a quark mass texture neatly arising from a hierarchical breaking of a U(2) flavour symmetry.

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Riccardo Barbieri, Lawrence J. Hall, Andrea Romanino. 1999-03-11. Precise tests of a quark mass texture. https://doi.org/10.1016/s0550-3213(99)00215-1

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