Supersymmetric 4D orientifolds of type IIA with D6-branes at angles

Abstract

We study a certain class of four-dimensional script N = 1 supersymmetric orientifolds for which the world-sheet parity transformation is combined with a complex conjugation in the compact directions. We investigate in detail the or orientifolds of the ℤ3, ℤ4, ℤ6 and ℤ′6 toroidal orbifolds finding solutions to the tadpole cancellation conditions for all models. Generally, all the massless spectra turn out to be non-chiral.