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arXiv · 1807.11917

Direct $CP$ violation from isospin symmetry breaking effects in PQCD

Gang Lü·Qin-Qin Zhi
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Abstract

We investigate the direct $CP$ violation for the decay process of $\bar{B}_{s}\rightarrow P(V)\pi^{0}$ (P,V refer to the pseudoscalar meson and vector meson, respectively) via isospin symmetry breaking effects from the $\pi^{0}-\eta-\eta'$ mixing mechanism in PQCD factorization approach. Isospin symmetry breaking arises from the electroweak interaction and the u-d quark mass difference by the strong interaction which are known to be tiny. However, we find that isospin symmetry breaking at the leading order shifts the $CP$ violation due to the new strong phases.

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Gang Lü, Qin-Qin Zhi. 2018-07-29. Direct $CP$ violation from isospin symmetry breaking effects in PQCD. https://arxiv.org/abs/1807.11917

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