$W$ boson mass and muon $g-2$ in a lepton portal dark matter model

Abstract: We study a lepton portal dark matter model, motivated by the deviation of the $W$ boson mass reported by the CDF collaboration. We introduce vector-like leptons and a scalar dark matter (DM) which exclusively couples to the extra leptons and muon. The one-loop corrections induced by the new particles can shift the $W$ boson mass. Besides, the discrepancy in the muon anomalous magnetic moment and the DM density can simultaneously be explained by this setup, if the vector-like lepton is lighter than 200 GeV and nearly degenerate with the DM particle. We also see that the constraints on such a light extra lepton from the collider experiments can be evaded due to the existence of the DM particle.