Branons are new degrees of freedom that appear in flexible brane-world models corresponding to brane fluctuations. These new fields can behave as standard weakly interacting massive particles (WIMPs) with a significant associated thermal relic density. We analyze the present constraints from their spontaneous annihilations into photons for Energetic Gamma-Ray Experiment Telescope (EGRET), Fermi-Large Area Telescope (LAT), and Major Atmospheric Gamma-Ray Imaging Cherenkov (MAGIC) telescopes, and the prospects for detection in future Cherenkov telescopes. In particular, we focus on possible signals coming from the Galactic center and different dwarf spheroidals, such as Draco, Sagittarius, Canis Major and SEGUE 1. We conclude that for those targets, present observations are below the sensitivity limits for branon detection by assuming standard dark matter distributions and no additional boost factors. However, future experiments such as the Cherenkov Telescope Array (CTA) could be able to detect gamma-ray photons coming from the annihilation of branons with masses higher than 150 GeV.

• Received 12 December 2011

DOI:https://doi.org/10.1103/PhysRevD.85.043505