Constraining branon dark matter from observations of the Segue 1 dwarf
  spheroidal galaxy with the MAGIC telescopes
  We present the first search for signatures of brane-world extra-dimensional
dark matter (DM) in the very-high-energy gamma-ray band by scrutinizing
observations of the dwarf spheroidal galaxy Segue 1 with the Major Atmospheric
Gamma Imaging Cherenkov (MAGIC) telescope system. Branons are new degrees of
freedom that appear within flexible brane-world models: they are weakly
interacting massive particles and natural DM candidates. The ground-based
gamma-ray telescopes MAGIC could indirectly detect branon DM in the multi-TeV
mass range by observing secondary products of DM annihilation into Standard
Model particles. In the absence of a signal, we place constraints on the branon
DM parameter space by using a binned likelihood analysis of almost 160-hours
deep exposure on the Segue 1 dwarf spheroidal galaxy by the MAGIC telescopes.
Our most stringent limit to the thermally-averaged annihilation cross-section
(at $95\%$ confidence level) corresponds to $ \langle \sigma v \rangle \simeq
1.4 \times 10^{-23}~\text{cm}^{3}\text{s}^{-1} $ at a branon mass of $ \sim
0.7~\text{TeV}$.
