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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K → μ + μ − as a third kaon golden mode
Abstract Recent progress has demonstrated that the K → μ + μ − decay carries clean short-distance information, attainable from a measurement of time-dependence sensitive to K L − K S interference effects. We review the ingredients that go into this proposed extraction, and discuss the sensitivity to the CKM parameter η ¯ as well as to various NP scenarios.
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- Award ID(s):
- 2014071
- PAR ID:
- 10434480
- Date Published:
- Journal Name:
- Journal of Physics: Conference Series
- Volume:
- 2446
- Issue:
- 1
- ISSN:
- 1742-6588
- Page Range / eLocation ID:
- 012034
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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