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arXiv · 1106.0375

Constraints on exotic lepton doublets with minimal coupling to the standard model

Sandy S. C. Law
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Abstract

We investigate the consequences of introducing a set of exotic doublet leptons which couple to the standard model leptons in a minimal way. Through these additional gauge invariant and renormalizable coupling terms, new sources of tree-level flavor changing currents are induced via mixing. In this work, we derive constraints on the parameters that govern the couplings to the exotic doublets by invoking the current low-energy experimental data on processes such as leptonic Z decays, $\ell \rightarrow 3 \ell'$, $\ell \rightarrow \ell' \gamma$, and $\mu$-$e$ conversion in atomic nuclei. Moreover, we have analyzed the role these doublets play on the lepton anomalous magnetic moments, and found that their contribution is negligible.

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Sandy S. C. Law. 2011-06-02. Constraints on exotic lepton doublets with minimal coupling to the standard model. https://doi.org/10.1007/jhep02(2012)127

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