Blowing-up the four-dimensional Z(3) orientifold

We study the blowing-up of the four-dimensional Z(3) orientifold of Angelan tonj, Bianchi, Pradisi, Sagnotti and Stanev (ABPSS) by giving nonzero vacuu m expectation values (VEV's) to the twisted sector moduli blowing-up modes. The blowing-up procedure induces a Fayet-Iliopoulos (FI) term for the "ano malous" U(1), whose magnitude depends linearly on the VEV's of the blowing- up modes. To preserve the N = 1 supersymmetry, non-Abelian matter fields ar e forced to acquire nonzero VEV's, thus breaking (some of) the non-Abelian gauge structure and decoupling some of the matter fields. We determine the form of the FI term, construct explicit examples of (non-Abelian) D and F a t directions, and determine the surviving gauge groups of the restabilized vacua. We also determine the mass spectra, for which the restabilization re duces the number of families.