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arXiv · 0812.0064

Fourth Generation Leptons and Muon $g-2$

Wei-Shu Hou·Fei-Fan Lee·Chien-Yi Ma
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Abstract

We consider the contributions to $g_μ-2$ from fourth generation heavy neutral and charged leptons, $N$ and $E$, at the one-loop level. Diagrammatically, there are two types of contributions: boson-boson-$N$, and $E$-$E$-boson in the loop diagram. In general, the effect from $N$ is suppressed by off-diagonal lepton mixing matrix elements. For $E$, we consider flavor changing neutral couplings arising from various New Physics models, which are stringently constrained by $μ\to eγ$. We assess how the existence of a fourth generation would affect these New Physics models.

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Wei-Shu Hou, Fei-Fan Lee, Chien-Yi Ma. 2009-01-15. Fourth Generation Leptons and Muon $g-2$. https://doi.org/10.1103/physrevd.79.073002

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