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arXiv · 1607.06832

Lepton flavor violating Z' explanation of the muon anomalous magnetic moment

Wolfgang Altmannshofer·Chien-Yi Chen·P. S. Bhupal Dev·Amarjit Soni
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Abstract

We discuss a minimal solution to the long-standing $(g-2)_μ$ anomaly in a simple extension of the Standard Model with an extra $Z'$ vector boson that has only flavor off-diagonal couplings to the second and third generation of leptons, i.e. $μ, τ, ν_μ, ν_τ$ and their antiparticles. A simplified model realization, as well as various collider and low-energy constraints on this model, are discussed. We find that the $(g-2)_μ$-favored region for a $Z'$ lighter than the tau lepton is totally excluded, while a heavier $Z'$ solution is still allowed. Some testable implications of this scenario in future experiments, such as lepton-flavor universality-violating tau decays at Belle 2, and a new four-lepton signature involving same-sign di-muons and di-taus at HL-LHC and FCC-ee, are pointed out. A characteristic resonant absorption feature in the high-energy neutrino spectrum might also be observed by neutrino telescopes like IceCube and KM3NeT.

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Wolfgang Altmannshofer, Chien-Yi Chen, P. S. Bhupal Dev, Amarjit Soni. 2016-07-22. Lepton flavor violating Z' explanation of the muon anomalous magnetic moment. https://doi.org/10.1016/j.physletb.2016.09.046

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