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arXiv · 2202.04430

Reappraisal of the minimal flavoured $Z^{\prime}$ scenario

Tirtha Sankar Ray·Avirup Shaw
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Abstract

Recent results from the intensity frontier indicate the tantalizing possibility of violation in lepton flavour universality. In light of this we revisit the minimal phenomenological $Z'$ model taking in account both vectorial and axial-vectorial flavour violating couplings to the charged leptons. We make a systematic study to identify the minimal framework that can simultaneously explain the recent results on anomalous magnetic moment of muon and electron while remaining in consonance with $R_{K^{(*)}}$, $B^0_s-\bar{B^0_s}$ mixing and angular observables in the $B^+\to K^{+*} \mu^+\mu^-$ channel reported by the LHCb collaboration. We demonstrate that the neutrino trident data imply a further ${\rm SU(2)}_L$ violation in the leptonic couplings of the exotic $Z'$.

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Tirtha Sankar Ray, Avirup Shaw. 2022-02-09. Reappraisal of the minimal flavoured $Z^{\prime}$ scenario. https://doi.org/10.1016/j.nuclphysb.2022.116065

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