A large muon EDM from dark matter

Abstract

We explore a model of dark matter (DM) that can explain the reported discrepancy in the muon anomalous magnetic moment and predict a large electric dipole moment (EDM) of the muon. The model contains a DM fermion and new scalars whose exclusive interactions with the muon radiatively generate the observed muon mass. Constraints from DM direct and indirect detection experiments as well as collider searches are safely evaded. The model parameter space that gives the observed DM abundance and explains the muon g – 2 anomaly leads to the muon EDM of dμ ≃ (4-5) × 10−22e cm that can be probed by the projected PSI muEDM experiment. Another viable parameter space even achieves $$ {d}_{\mu }=\mathcal{O}\left({10}^{-21}\right) $$ d μ = O 10 − 21 e cm reachable by the ongoing Fermilab Muon g − 2 experiment and the future J-PARC Muon g − 2/EDM experiment.

Status of the muEDM Experiment at PSI

“…Assuming CPT symmetry, the latter implies a violation of the CP symmetry. If an EDM measurement exceeds the SM prediction, it could suggest physics beyond the Standard Model (BSM) [4][5][6][7], thus refining our understanding of the universe.…”