Introduction
This is a study motivated by a theory of dark matter, first suggested by Nima Arkani-Hamed in this arXiv paper. He and Neal Weiner made a study of how it could be seen in the LHC and wrote this paper.
We are currently working on the extension to this theory, suggested by Itay Yavin and others, which can be found here.
The signature is many leptons (electrons or muons) in the same cone, resembling a jet. For ATLAS, the leptons usually fall in the same ROI (Region of Interest), requiring additional trigger chains to be sensitive to these events.