https://doi.org/10.1140/epjc/s10052-022-10776-1
Regular Article - Theoretical Physics
Prospects for a flavour violating 
explanation of 
Laboratoire de Physique de Clermont (UMR 6533), CNRS/IN2P3, Univ. Clermont Auvergne, 4 Av. Blaise Pascal, Aubière, 63178, Cedex, France
a
jonathan.kriewald@clermont.in2p3.fr
Received:
4
July
2022
Accepted:
31
August
2022
Published online:
28
September
2022
The apparent tensions emerging from the comparison of experimental data of the anomalous magnetic moments of the muon and electron to the Standard Model predictions () could be interpreted as a potential signal of New Physics. Models encompassing a light vector boson have been known to offer a satisfactory explanation to 
, albeit subject to stringent experimental constraints. Here we explore a minimal extension of the Standard Model via a leptophilic vector boson , under the hypothesis of strictly flavour-violating couplings of the latter to leptons. The most constraining observables to this ad-hoc construction emerge from lepton flavour universality violation (in Z and 
decays) and from rare charged lepton flavour violating transitions. Once these are accommodated, one can saturate the tensions in , but 
is predicted to be Standard Model-like. We infer prospects for several observables, including leptonic Z decays and several charged lepton flavour violating processes. We also discuss potential signatures of the considered at a future muon collider, emphasising the role of the 
forward-backward asymmetry as a key probe of the model.
© The Author(s) 2022
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