Searches for Heavy Neutrinos and Supersymmetry in Dilepton Events at the ATLAS Experiment

Two searches for new physics in events containing exactly two leptons performed at the ATLAS experiment are presented. The first searches for a new family of neutrinos in order to explain the observed small masses of the known neutrinos, while the second searches for the electroweak production of Supersymmetric particles. The Standard Model backgrounds are common between the two analyses, and an emphasis will be placed on the estimation techniques used. In both cases, the observed data candidates are found to be in agreement with the estimated Standard Model background.