Leptonic anomalous magnetic moments in $\nu$SMEFT

Understand

We investigate contributions to the anomalous magnetic moments of charged leptons in the neutrino-extended Standard Model Effective Field Theory ($\nu$SMEFT).

• We discuss how $\nu$SMEFT operators can contribute to a lepton's magnetic moment at one- and two-loop order.
• We show that only one operator can account for existing electronic and muonic discrepancies, assuming new physics appears above $1$ TeV.
• In particular, we find that a right-handed charged current in combination with minimal sterile-active mixing can explain the discrepancy for sterile neutrino masses of $\mathcal O(100)$ GeV while avoiding direct and indirect constraints.