The Cp-conserving Direction
نویسنده
چکیده
A symmetry transformation is well defined in the case of an invariant theory, being the corresponding operator undetermined otherwise. However, we show that, even with CP violation, it is possible to determine the CP transformation by separating the Lagrangian of the Standard Model in a CP-conserving and a CP-violating part, in a unique way, making use of the empirically known quark mixing hierarchy. To O(λ) for the Bd-system, the CP conserving direction matches one of the sides of the (bd) unitarity triangle. We use this determination to calculate the rephasing invariant parameter ε, which measures CP-mixing in the B − B̄ system. IFIC, Centro Mixto Univ. Valencia CSIC, E-46100 Burjasot (Valencia), Spain; [email protected] Departamento de F́ısica Teórica, Univ. Valencia, E-46100 Burjassot (Valencia), Spain; [email protected]
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ar X iv : h ep - p h / 98 07 43 0 v 2 2 9 Ju n 19 99 THE CP - CONSERVING DIRECTION
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