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arXiv · 2403.00983

Heavy neutral lepton search and $\mu \to e \gamma$ constraints in case of type-I seesaw

Stefano Morisi
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Abstract

Within type-I seesaw mechanism it is possible to have large (order one) light-heavy neutrino mixing even in case of low right-handed neutrino mass scale (of the order of GeV). This implies large lepton flavor violation. As example we consider the process $\mu \to e \gamma$ that can have a branching up to $10^{-8}$ within type-I seesaw (in contrast with the tiny value $10^{-54}$ expected). Such an enhancing of lepton flavor violation can be used to constraint the parameter space of long lived particle experiments.

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Stefano Morisi. 2024-03-01. Heavy neutral lepton search and $\mu \to e \gamma$ constraints in case of type-I seesaw. https://arxiv.org/abs/2403.00983

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