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arXiv · 0711.0733

Electroweak-scale mirror fermions, $μ\to e γ$ and $τ\to μγ$

P. Q. Hung
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Abstract

The Lepton Flavour Violating (LFV) processes $μ\to e γ$ and $τ\to μγ$ are estimated in a model of electroweak-scale right-handed neutrinos. The present bounds on the branching ratios, $B(μ\to e γ)< 1.2 \times 10^{-11}$, $B(τ\to μγ) < 6.8 \times 10^{-8}$ (BaBar) and $< 4.5 \times 10^{-8}$ (Belle), puts strong constraints on the parameters of the model. This constraint links low energy rare decay processes to high-energy phenomena (e.g. decay lengths of the mirror charged leptons which are important in the search for the telltale like-sign dilepton events present in the model of electroweak-scale right-handed neutrinos).

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P. Q. Hung. 2007-12-11. Electroweak-scale mirror fermions, $μ\to e γ$ and $τ\to μγ$. https://doi.org/10.1016/j.physletb.2007.12.005

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