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arXiv · 2107.14685

Constraints from the CHARM experiment on Heavy Neutral Leptons with tau mixing

Iryna Boiarska·Alexey Boyarsky·Oleksii Mikulenko·Maksym Ovchynnikov
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Abstract

We re-analyze the results of the searches for Heavy Neutral Leptons (HNLs) by the CHARM experiment. We study HNL decay channel $N\to e^{+}e^{-}\nu/\mu^{+}\mu^{-}\nu$ and show that, in addition to the constraints on the HNL's mixings with $\nu_e$ or $\nu_{\mu}$, the same data also implies limits on the HNLs that mix only with $\nu_{\tau}$ and have masses in the range $380 \text{ MeV}<m_{N}\lesssim 1.6\text{ GeV}$ - the region in the parameter space that was considered in the literature as a target for HNLs searches.

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Iryna Boiarska, Alexey Boyarsky, Oleksii Mikulenko, Maksym Ovchynnikov. 2021-07-30. Constraints from the CHARM experiment on Heavy Neutral Leptons with tau mixing. https://doi.org/10.1103/physrevd.104.095019

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