Supersymmetric Orientifolds in 6D with D-Branes at Angles

TL;DR

This paper introduces a new class of six-dimensional N=1 supersymmetric orientifolds involving D-branes at angles, with twisted sectors contributing to tadpoles, leading to anomaly-free spectra.

Contribution

It presents the construction and analysis of novel orientifolds with permutation symmetries and intersecting D-branes, expanding the landscape of consistent supersymmetric models.

Findings

Twisted sectors contribute to Klein bottle amplitudes.

All models studied are anomaly-free.

Explicit spectra for Z_3, Z_4, Z_6 orientifolds are obtained.

Abstract

We study a new class of N=1 supersymmetric orientifolds in six space-time dimensions. The world-sheet parity transformation is combined with a permutation of the internal complex coordinates. In contrast to ordinary orientifolds the twisted sectors contribute to the Klein bottle amplitude leading to new tadpoles to be cancelled by twisted open string sectors. They arise from open strings stretched between D7-branes intersecting at non-trivial angles. We study in detail the Z_3, Z_4 and Z_6 permutational orientifolds obtaining in all cases anomaly free massless spectra.