Pseudo-Nambu-Goldstone Dark Matter in Flux Compactification

Abstract

We study a six-dimensional U(1)${}_{\ddot{I}}‡$ gauge theory compactified on a magnetized torus, where the zero mode of the extra-dimensional gauge field (a Wilson-line (WL) scalar field) plays the role of a pseudo-Nambu-Goldstone (pNG) dark matter (DM) candidate. The pNG DM is naturally included by construction without introducing an additional scalar field. We show that the leading spin-independent DM-nucleus amplitude is suppressed by momentum transfer in our model as expected from the pNG DM model. This suppression allows the model to evade the current severe direct-detection bounds while achieving the observed thermal relic abundance in well-defined regions of parameter space.

18 pages, 4 figures