Stability of Electroweak Vacuum and Supersymmetric Contribution to Muon g-2

We study the stability of the electroweak vacuum in the supersymmetric (SUSY) standard model (SM), paying particular attention to its relation to the SUSY contribution to the muon anomalous magnetic moment $a_\mu$. If the SUSY contribution to $a_\mu$ is sizable, the electroweak vacuum may become unstable because of enhanced trilinear scalar interactions in particular when the sleptons are heavy. Consequently, assuming enhanced SUSY contribution to $a_\mu$, an upper bound on the slepton masses is obtained. We give a detailed prescription to perform a full one-loop calculation of the decay rate of the electroweak vacuum for the case that the SUSY contribution to $a_\mu$ is enhanced. We also give an upper bound on the slepton masses as a function of the SUSY contribution to $a_\mu$.