Search for heavy neutral lepton production in $K^{+}$ decays

Abstract

A search for heavy neutral lepton production in $K^{+}$ decays using a data sample collected with a minimum bias trigger by the NA62 experiment at CERN in 2015 is reported. Upper limits at the $10^{-7}$ to $10^{-6}$ level are established on the elements of the extended neutrino mixing matrix $|U_{\ell 4}{|}^2$ ($\ell =e,\mu$) for heavy neutral lepton mass in the range $170-448\mathrm{MeV}/c^2$. This improves on the results from previous production searches in $K^{+}$ decays, setting more stringent limits and extending the mass range.

Version accepted for publication in Phys.Lett.B (12/01/2018)

References in corpus (2)

• Search for heavy neutrinos in $K^{+}\to {\mu }^{+}{\nu }_H$ decays
• Test of Lepton Flavour Universality in K+ --> l+nu Decays

Cited by in corpus (1)

• Probing the Seesaw Mechanism and Leptogenesis with the International Linear Collider