Lepton Flavor Violation in the Standard Model with general Dimension-Six Operators

Abstract

We study lepton flavor observables in the Standard Model (SM) extended with all dimension-$6$ operators which are invariant under the SM gauge group. We calculate the complete one-loop predictions to the radiative lepton decays $\mu\to e\gamma$, $\tau \to \mu \gamma$ and $\tau\to e\gamma$ as well as to the closely related anomalous magnetic moments and electric dipole moments of charged leptons, taking into account all dimension-$6$ operators which can generate lepton flavor violation. Also the 3-body flavor violating charged lepton decays $\tau^\pm \to \mu^\pm \mu^+ \mu^-$, $\tau^\pm\to e^\pm e^+ e^- $, $\tau^\pm \to e^\pm \mu^+ \mu^- $, $\tau^\pm \to \mu^\pm e^+ e^- $, $\tau^\pm \to e^\mp \mu^\pm \mu^\pm$, $\tau^\pm \to \mu^\mp e^\pm e^\pm $ and $\mu^\pm \to e^\pm e^+ e^-$ and the $Z^0$ decays $Z^0\to\ell_i^+\ell_j^-$ are considered, taking into account all tree-level contributions.