K → μ+μ− beyond the standard model
A bstract We analyze the New Physics sensitivity of a recently proposed method to measure the CP-violating $$\mathcal{B}$$ B ( K S → μ + μ − ) ℓ =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 $$\mathcal{B}$$ B ( K L → π 0 $$\nu \overline{\nu}$$ ν ν ¯ ). We find that simple NP models can significantly enhance $$\mathcal{B}$$ B ( K S → μ + μ − ) ℓ =0 , making this mode a very promising probe of physics beyond the standard model in the kaon sector.
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Award ID(s):
Publication Date:
NSF-PAR ID:
10345893
Journal Name:
Journal of High Energy Physics
Volume:
2022
Issue:
3
ISSN:
1029-8479
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