Multi-frequency search for Dark Matter: the role of HESS, CTA, and SKA
  Dark Matter (DM) remains a vital, but elusive, component in our current
understanding of the universe. Accordingly, many experimental searches are
devoted to uncovering its nature. However, both the existing direct detection
methods, and the prominent $\gamma$-ray search with the Fermi Large Area
Telescope (Fermi-LAT), are most sensitive to DM particles with masses below 1
TeV, and are significantly less sensitive to the hard spectra produced in
annihilation via heavy leptons. The High Energy Stereoscopic System (HESS) has
had some success in improving on the Fermi-LAT search for higher mass DM
particles, particularly annihilating via heavy lepton states. However, the
recent discovery of high J-factor dwarf spheroidal galaxies by the Dark Energy
Survey (DES) opens up the possibility of investing more HESS observation time
in the search for DM $\gamma$-ray signatures in dwarf galaxies. This work
explores the potential of HESS to extend its current limits using these new
targets, as well as the future constraints derivable with the up-coming
Cherenkov Telescope Array (CTA). These limits are further compared with those
we derived at low radio frequencies for the Square Kilometre Array (SKA).
Finally, we explore the impact of HESS, CTA, and Fermi-LAT on the phenomenology
of the "Madala" boson hypothesized based on anomalies in the data from the
Large Hadron Collider (LHC) run 1. The power of these limits from differing
frequency bands is suggestive of a highly effective multi-frequency DM hunt
strategy making use of both existing and up-coming Southern African telescopes.
