2006/07/31 by A. Font, Anamarı́a Font, Luis E. Ibáñez +3 · 1 citation
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #hep-ph #hep-th
paper · pdf · doi:10.1088/1126-6708/2006/09/080
published as JHEP0609:080,2006 · 63 pages, 11 figures. Typos corrected and comments added
arxiv created 2006/08/23 · openalex publication_date 2006/09/29 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Up to now chiral type IIA vacua have been mostly based on intersecting D6-branes wrapping special Lagrangian 3-cycles on a CY three-fold. We argue that there are additional BPS D-branes which have so far been neglected, and which seem to have interesting model-building features. They are coisotropic D8-branes, in the sense of Kapustin and Orlov. The D8-branes wrap 5-dimensional submanifolds of the CY which are trivial in homology, but contain a worldvolume flux that induces D6-brane charge on them. This induced D6-brane charge not only renders the D8-brane BPS, but also creates D=4 chirality when two D8-branes intersect. We discuss in detail the case of a type IIA Z2 x Z2 orientifold, where we provide explicit examples of coisotropic D8-branes. We study the chiral spectrum, SUSY conditions, and effective field theory of different systems of D8-branes in this orientifold, and show how the magnetic fluxes generate a superpotential for untwisted Kahler moduli. Finally, using both D6-branes and coisotropic D8-branes we construct new examples of MSSM-like type IIA vacua.