Implications of the muon anomalous magnetic moment and Higgs-mediated flavor changing neutral currents

Abstract

In the light of the recent measurement of the muon anmalous magnetic moment $a_μ$ by the Muon $(g-2)$ Collaboration, we examine the contribution to $a_μ$ from the exchange of flavor changing scalars. Assuming that the heavier generations have larger flavor changing couplings, we obtain a bound on $μ- τ$ Yukawa coupling for a given scalar mass. Constraints on other flavor changing/conserving couplings are also obtained from the lepton flavor violating decays of muon and tau lepton, and bounds on the branching ratio of $τ\to 3 e$, $μ\to 3 e$ and $τ\to e μe$ processes are predicted.