Supersymmetry Breaking by Type II Seesaw Assisted Anomaly Mediation

Abstract

Anomaly mediated supersymmetry breaking, when implemented in the minimal supersymmetric standard model, is known to suffer from the problem of negative slepton mass squared leading to the breakdown of electric charge conservation. We show, however, that when the minimal supersymmetric standard model is extended to explain small neutrino masses by including a pair of superheavy Higgs triplet superfields (the type II seesaw mechanism), the slepton masses can be deflected from the pure anomaly mediated supersymmetry breaking trajectory and become positive. In the simple model we present in this paper, the seesaw scale is about 10¹³–10¹⁴ GeV. Gauge coupling unification can be maintained by embedding the triplet to SU(5) 15-multiplet. In this scenario, the b-ino is the lightest supersymmetric particle and its mass is nearly degenerate with the next-to-lightest supersymmetric particle slepton when the triplet mass is right around the seesaw scale.