%0 Journal Article
%T D-brane probes on G2 Orbifolds
%A G. Ferretti
%A P. Salomonson
%A D. Tsimpis
%J Physics
%D 2001
%I arXiv
%R 10.1088/1126-6708/2002/03/004
%X We consider type IIB string theory on a seven dimensional orbifold with holonomy in G2. The motivation is to use D1-branes as probes of the geometry. The low energy theory on the D1-brane is a sigma-model with two real supercharges (N = (1,1) in two dimensional language). We study in detail the closed and open string sectors and propose a coupling of the twisted fields to the brane that modifies the vacuum moduli space so that the singularity at the origin is removed. Instead of coming from D-terms, which are not present here, the modification comes from a ``twisted'' mass term for the seven scalar multiplets on the brane. The proposed mechanism involves a generalization of the moment map.
%U http://arxiv.org/abs/hep-th/0111050v3