Heterotic mini-landscape (II): completing the search for MSSM vacua in a   Z_6 orbifold
  We complete our search for MSSM vacua in the Z_6-II heterotic orbifold by including models with 3 Wilson lines. We estimate the total number of inequivalent models in this orbifold to be 10^7. Out of these, we find almost 300 models with the exact MSSM spectrum, gauge coupling unification and a heavy top quark. Models with these features originate predominantly from local GUTs. The scale of gaugino condensation in the hidden sector is correlated with properties of the observable sector such that soft masses in the TeV range are preferred. 
Oleg Lebedev, Hans Peter Nilles, Saul Ramos-Sanchez, Michael Ratz,   Patrick K.S. Vaudrevange