Probing the messenger of supersymmetry breaking by the muon anomalous magnetic moment

Abstract

Motivated by the recently measured muon's anomalous magnetic moment $a_{\mu }$, we examine the supersymmetry contribution to $a_{\mu }$ in various mediation models of supersymmetry breaking which lead to predictive flavor conserving soft parameters at high energy scale. The studied models include dilaton/modulus-mediated models in heterotic string/$M$ theory, gauge-mediated model, no-scale or gaugino-mediated model, and also the minimal and deflected anomaly-mediated models. For each model, the range of $a_{\mu }^{SUSY}$ allowed by other experimental constraints, e.g. b --> s\gamma and the collider bounds on superparticle masses, is obtained together with the corresponding parameter region of the model. Gauge-mediated models with low messenger scale can give any $a_{\mu }^{SUSY}$ within the $2\sigma$ bound. In many other models, b --> s\gamma favors $a_{\mu }^{SUSY}$ smaller than either the $-1\sigma$ value ($26\times 10^{-10}$) or the central value ($42\times 10^{-10}$).

Comments: RevTeX, 29 pages, 14 eps figures, figure for deflected anomaly mediation is corrected, reference added