Supersymmetric Intersecting Branes on the Type IIA T^6/Z_4 orientifold

TL;DR

This paper explores supersymmetric intersecting D6-branes on a specific Type IIA orientifold, constructing models that can realize a three-generation Pati-Salam GUT and its standard-like breaking via brane recombination.

Contribution

It introduces fractional 3-cycles from untwisted and twisted sectors in the orbifold, providing an integral basis for homology and demonstrating model building with supersymmetric branes.

Findings

Constructed a three-generation Pati-Salam model.

Demonstrated supersymmetric brane recombination to a standard-like model.

Established a homology basis involving the E8 Cartan matrix.

Abstract

We study supersymmetric intersecting D6-branes wrapping 3-cycles in the Type IIA T^6/Z_4 orientifold background. As a new feature, the 3-cycles in this orbifold space arise both from the untwisted and the Z_2 twisted sectors. We present an integral basis for the homology lattice, H_3(M,Z), in terms of fractional 3-cycles, for which the intersection form involves the Cartan matrix of E8. We show that these fractional D6-branes can be used to construct supersymmetric brane configurations realizing a three generation Pati-Salam model. Via brane recombination processes preserving supersymmetry, this GUT model can be broken down to a standard-like model.