superstrings;
open strings;
compactification;
orbifold;
D-branes;
orientifold;
D O I:
10.1016/0550-3213(96)00356-2
中图分类号:
O412 [相对论、场论];
O572.2 [粒子物理学];
学科分类号:
摘要:
We study string theory propagating on R(6)xK3 by constructing orientifolds of Type IIB string theory compactified on the T-4/Z(N) orbifold limits of the K3 surface. This generalises the Z(2) case studied previously. The orientifold models studied may be divided into two broad categories, sometimes related by T-duality. Models in category A require either both D5- and D9-branes, or only D9-branes, for consistency. Models in category B require either only D5-branes, or no D-branes at all. This latter case is an example of a consistent purely closed unoriented string theory. The spectra of the resulting six-dimensional N = 1 supergravity theories are presented. Precise statements are made about the relation of the Z(N) ALE spaces and D5-branes to instantons in the dual heterotic string theory.