Search for Supersymmetry in events with four or more leptons in 13 fb−1 pp collisions at √s = 8 TeV with the ATLAS detector

Results of a search for supersymmetry in events with four or more leptons (electrons or muons) are presented. The analysis uses a sample corresponding to 13.0 fb⁻¹ of proton-proton collision data delivered by the LHC at √s = 8 TeV and recorded by the ATLAS detector. Two signal regions are defined with a selection vetoing Z boson production. The first signal region has large missing transverse momentum (Etmiss > 50GeV), where 1 event is observed while 0.25+0.29-0.25 are expected from Standard Model processes. The second requires large total effective mass (meff > 300GeV), where 2 events are observed while 1.2±0.5 are expected from Standard Model processes. Limits are placed on various R-parity violating simplified models, where the lightest supersymmetric particle (chi_1^0) decays promptly to first- and second-generation leptons. Considering one other sparticle at a time, pair-produced and decaying directly to a chi_1^0, charged Winos are excluded up to a mass of ∼ 710 GeV, left-handed sleptons up to ∼ 450 GeV, sneutrinos up to ∼ 410 GeV and gluinos up to ∼ 1300 GeV.