Three-Family Models from a Heterotic Orbifold on the E_6 Root Lattice

Understand

We classify N=1 orbifolds on the E_6 root lattice and investigate explicit model constructions on the Z_3xZ_3 orbifold in heterotic string theory.

• Interestingly some of the twisted sectors from the Z_3xZ_3 orbifold on the E_6 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.