The stau exchange contribution to muon g−2 in the decoupling solution

Abstract

We study the possibility that the lepton-flavor changing process can induce the suitable magnitude of the muon anomalous magnetic moment (g_\mu -2) in the decoupling solution to the flavor problem in the minimal supersymmetric standard model. Our analyses introduce the flavor mixings of left- and right-handed stau and smuon phenomenologically. It is found that if both the left- and right-handed sleptons have sizable flavor mixings, the correction to g_\mu -2 from the lighter slepton can reach to 10^{-9} while the correction to the branching ratio of \tau \to \mu \gamma satisfies the current experimental bound. On the other hand, when only the left-handed or right-handed sleptons have the large flavor mixing, the suitable magnitude of the correction to g_\mu-2 is not realized owing to the experimental bound of \tau \to \mu \gamma.