Semi-visible dark photon in a model with vector-like leptons for the $(g-2)_{e,\mu}$ and $W$-boson mass anomalies

TL;DR

This paper introduces a semi-visible dark photon model with vector-like leptons that simultaneously explains the anomalies in the electron and muon g-2 measurements and the W-boson mass deviation, avoiding certain experimental constraints.

Contribution

It proposes a novel semi-visible dark photon model with vector-like leptons that accounts for multiple recent anomalies in particle physics.

Findings

Explains the electron and muon g-2 anomalies via vector-like leptons and gauge kinetic mixing.

Accounts for the W-boson mass deviation through vector-like lepton loops.

Circumvents dark photon constraints with semi-invisible decay channels.

Abstract

We propose a model realizes that a semi-visible dark photon which can contribute to the anomalous magnetic moment ($g-2$) of both electron and muon. In this model, the electron $g-2$ is deviated from the Standard Model (SM) prediction by the 1-loop diagrams involving the vector-like leptons, while that of muon is deviated due to a non-vanishing gauge kinetic mixing with photons. We also argue that the $W$-boson mass can be deviated from the SM prediction due to the vector-like lepton loops, so that the value obtained by the CDF II experiment can be explained. Thus, this model simultaneously explains the recent three anomalies in $g-2$ of electron and muon as well as the $W$-boson mass. The constraints on the $\mathcal{O}(1)~\mathrm{GeV}$ dark photon can be avoided because of the semi-invisible decay of the dark photon, $A^\prime \to 2 N \to 2\nu \,2\chi \to 2\nu \,4e$, where $N$ is a SM singlet vector-like neutrino and $\chi$ is a CP-even Higgs boson of the $U(1)^\prime$ gauge symmetry.