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arXiv · 1707.09297

$CP$ asymmetries in charm decays into neutral kaons

Di Wang·Fu-Sheng Yu·Hsiang-nan Li
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Abstract

We find a new $CP$-violation effect in charm decays into neutral kaons, which results from the interference between two tree (Cabibbo-favored and doubly Cabibbo-suppressed) amplitudes with the mixing of final-state mesons. This effect, estimated to be of an order of $10^{-3}$, is much larger than the direct $CP$ asymmetries in these decays, but missed in the literature. It can be revealed by measuring the difference of the time-dependent $CP$ asymmetries in the $D^{+}\toπ^{+}K_S^0$ and $D_{s}^{+}\to K^{+} K_S^0$ modes, which are accessible at the LHCb and Belle II experiments. If confirmed, the new effect has to be taken into account, as the above direct $CP$ asymmetries are used to search for new physics.

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Di Wang, Fu-Sheng Yu, Hsiang-nan Li. 2017-10-26. $CP$ asymmetries in charm decays into neutral kaons. https://doi.org/10.1103/physrevlett.119.181802

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