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arXiv · 2110.11752

QCD-based estimate of direct $CP$ asymmetry in charm decays

Alexander Khodjamirian
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Abstract

I discuss the calculation of the direct CP-asymmetry in $D\to \pi^+\pi^-$ and $D\to K^+K^- $ decays with the method of QCD light-cone sum rules. The main result is the upper limit for the difference of the two asymmetries $\left|\Delta a_{CP}^{dir}\right| < 0.020\pm 0.003\%$ which is significantly smaller than the recent measurement of this quantity by the LHCb collaboration

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Alexander Khodjamirian. 2021-10-22. QCD-based estimate of direct $CP$ asymmetry in charm decays. https://arxiv.org/abs/2110.11752

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