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Puzzle of W Leptonic Decay Branching Fractions and Gauge Model of Generation Nonuniversality

Xiao-Yuan Li·Ernest Ma
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Abstract

Lepton generation universality holds very well in Z decays, but appears to be violated in recent LEP data of W leptonic decay branching fractions. If this trend persists, a consistent and natural explanation is a model of generation nonuniversality, based on the gauge group SU(2)_L X U(1)_R X U(1)_{B-L}.

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Xiao-Yuan Li, Ernest Ma. 2005-07-01. Puzzle of W Leptonic Decay Branching Fractions and Gauge Model of Generation Nonuniversality. https://arxiv.org/abs/hep-ph/0507017

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