Towards the supersymmetric standard model from intersecting D6-branes on the Z_6' orientifold

TL;DR

This paper constructs supersymmetric intersecting D6-brane models on the Z_6' orientifold aiming to realize the standard model, analyzing intersection conditions and matter content to achieve realistic particle spectra.

Contribution

It introduces explicit constructions of N=1 supersymmetric fractional branes on the Z_6' orientifold that can produce the standard model spectrum with correct intersection properties.

Findings

Identified intersection number conditions for chiral spectrum

Provided explicit brane configurations satisfying these conditions

Showed different lattice choices lead to varied physical models

Abstract

We construct N=1 supersymmetric fractional branes on the Z_6' orientifold. Intersecting stacks of such branes are needed to build a supersymmetric standard model. If a,b are the stacks that generate the SU(3)_c and SU(2)_L gauge particles, then, in order to obtain just the chiral spectrum of the (supersymmetric) standard model (with non-zero Yukawa couplings to the Higgs multiplets), it is necessary that the number ofintersections a \circ b of the stacks a and b, and the number of intersections a \circ b' of a with the orientifold image b' of b satisfy (a \circ b,a \circ b')=\pm(2,1) or \pm(1,2). It is also necessary that there is no matter in symmetric representations of the gauge group, and not too much matter in antisymmetric representations, on either stack. We provide a number of examples having these properties. Different lattices give different solutions and different physics.