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arXiv · hep-ph/9209294

Particle Width Effect on $CP$-Violating Asymmetries

Jiang Liu
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Abstract

$CP$-violating asymmetries calculated from the Breit-Wigner approximation for unstable particle propagators violate $CPT$. A formalism satisfying $CP$ invariance and unitarity is presented. Applications are given to $t$ decays. For the decay $t\to bν_τ\barτ$ in a class of $CP$-violating models the $CP$-violating asymmetry turns out to be $10^{-4}$ times smaller than the previously reported results.

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Jiang Liu. 1992-09-29. Particle Width Effect on $CP$-Violating Asymmetries. https://doi.org/10.1103/physrevd.47.r1741

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