Three-Family Models from a Heterotic Orbifold on the E6 Root Lattice

We classify N = 1 orbifolds on the E6 root lattice and investigate explicit model constructions on the Z3×Z3 orbifold in heterotic string theory. Interestingly some of the twisted sectors from the Z3×Z3 orbifold on the E6 root lattice have just three fixed tori respectively, and generate three degenerate massless states. We also found three point functions with flavor mixing terms. We assume only non-standard gauge embeddings and find that they lead to three-family SU(5) and SO(10) GUT-like models. These models also include strongly coupled sectors in the low energy and messenger states charged with both hidden and visible sectors. ∗E-mail address: [email protected]