D = 4, N=1, type IIB orientifolds

G. ALDAZABAL; A. FONT; L.E. IBANEZ; G. VIOLERO

NUCLEAR PHYSICS B

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 1998

0550-3213

We study different aspects of the construction of D = 4, N = 1 type IIB orientifolds based on toroidal . We find that tadpole cancellation conditions are in general more constraining than in six dimensions and that the standard Gimon-Polchinski orientifold projection leads to the impossibility of tadpole cancellations in a number of N orientifolds with even N including 4, 8, 8′ and . We construct  ×  orientifolds with different configurations of 9-branes, 5-branes and 7-branes, most of them chiral. Models including the analogue of discrete torsion are constructed and shown to have features previously conjectured on the basis of F-theory compactified on four-folds. Different properties of the D = 4, N = 1 models obtained are discussed including their possible heterotic duals and effective low-energy action. These models have in general more than one anomalous U(1) and the anomalies are cancelled by a D = 4 generalized Green-Schwarz mechanism involving dilaton and moduli fields.