Search for New Physics in Events with Three Charged Leptons with the ATLAS detector

A generic search for anomalous production of events with at least three charged leptons is presented. The search uses a $pp$-collision data sample at a center-of-mass energy of $\sqrt{s} = 8\TeV$ corresponding to 20.3$fb^{-1}$ of integrated luminosity collected in 2012 by the ATLAS detector at the Large Hadron Collider. Events are required to contain at least two electrons or muons, or one of each, while the third lepton may either be an additional electron or muon, or a hadronically decaying tau lepton. No significant excess above backgrounds expected from Standard Model processes is observed. Results are presented as upper limits on event yields from non-Standard-Model processes producing at least three prompt, isolated leptons, given as functions of lower bounds on several kinematic variables. Fiducial efficiencies for model testing are also provided.