On a NAHE variation

Correspondence between free fermionic models with Z2⊗Z2 twist (especially of the NAHE class) and orbifold models with a similar twist has received further attention recently. Our NAHE variation also involves a Z2⊗Z2 twist and offers additional understanding regarding the free fermion/orbifold correspondence. Further, models based on this NAHE variation offer some different phenomenological features compared to NAHE-based models. In particular, the more compact Z2⊗Z2 twist of the NAHE variation offers a range of mirror models not possible from NAHE-based models. Examples of such models are presented.