Gaugino Condensation with a Doubly Suppressed Gravitino Mass
  Supersymmetry breakdown via gaugino condensation in heterotic string theory can lead to models with a doubly suppressed gravitino mass. A TeV scale gravitino can emerge from a condensate as large as the grand unified scale. We analyze the properties of these models and discuss applications for particle physics and cosmology. 
Valeri Lowen, Hans Peter Nilles, Andrea Zanzi