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arXiv · 2112.05801

$K\to\mu^+\mu^-$ beyond the standard model

Avital Dery·Mitrajyoti Ghosh
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Abstract

We analyze the New Physics sensitivity of a recently proposed method to measure the CP-violating ${\cal B}(K_S\to\mu^+\mu^-)_{\ell=0}$ decay rate using $K_S - K_L$ interference. We present our findings both in a model-independent EFT approach as well as within several simple NP scenarios. We discuss the relation with associated observables, most notably ${\cal B}(K_L\to\pi^0\nu\bar\nu)$. We find that simple NP models can significantly enhance ${\cal B}(K_S\to\mu^+\mu^-)_{\ell=0}$, making this mode a very promising probe of physics beyond the standard model in the kaon sector.

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Avital Dery, Mitrajyoti Ghosh. 2021-12-10. $K\to\mu^+\mu^-$ beyond the standard model. https://doi.org/10.1007/jhep03(2022)048

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