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arXiv · 2405.10905

$K\to\pi\nu\bar\nu$ spectra and NA62 interpretation

Martin Gorbahn·Ulserik Moldanazarova·Kai Henryk Sieja·Emmanuel Stamou·Mustafa Tabet
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Abstract

Using the measured and projected invisible mass spectrum of the $K^+\to\pi^+\nu\bar\nu$ mode, we determine the current and future constraints within the model-independent framework of the weak effective theory at dimension-six. We work in two different operator bases depending whether neutrinos are Majorana or Dirac fermions. This makes it possible to transparently incorporate mass effects of additional sterile neutrinos for all operators.

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Martin Gorbahn, Ulserik Moldanazarova, Kai Henryk Sieja, Emmanuel Stamou, Mustafa Tabet. 2024-05-17. $K\to\pi\nu\bar\nu$ spectra and NA62 interpretation. https://arxiv.org/abs/2405.10905

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