  Dark matter annihilation into photons in our galaxy would constitute an
exciting indirect signal of its existence, as underscored by tentative evidence
for 130 GeV dark matter in Fermi/LAT data. Models that give a large
annihilation cross section into photons typically require the dark matter to
couple to, or be composed of, new charged particles, that can be produced in
colliders. We consider the LHC constraints on some representative models of
these types, including the signals of same-sign dileptons, opposite-sign
dileptons, events mimicking the production and decay of excited leptons,
four-photon events, resonant production of composite vectors decaying into two
photons, and monophoton events.
