Confronting the Fermi Line with LHC data: an Effective Theory of Dark Matter Interaction with Photons

We describe an effective theory of interaction between pairs of dark matter particles and pairs of photons. Such an interaction could accomodate $\chi\bar{\chi}\rightarrow\gamma\gamma$ processes which might be the cause of the observed feature in the FermiLAT spectrum, as well as $\gamma^*/Z\rightarrow \gamma\chi\bar{\chi}$ processes, which would predict excesses at the LHC in the $\gamma+\missET$ final-state. We reinterpret an ATLAS $\gamma+\missET$ analysis and the observed Fermi feature in the parameter space of our new effective theory to assess their consistency.