Constructing omega-stable structures: Rank 2 fields

We provide a general framework for studying the expansion of strongly minim al sets by adding additional relations in the style of Hrushovski. We intro duce a notion of separation of quantifiers which is a condition on the clas s of expansions of finitely generated models for the expanded theory to hav e a countable omega-sarurated model. We apply these results to construct fo r each sufficiently fast growing finite-to-one function mu from 'primitive extensions' to the natural numbers a theor T-mu of an expansion of an algeb raically closed field which has Morley rank 2. Finally. we show that if mu is not finite-to-one the theory may not be omega-stable.