Search for electroweak production of supersymmetric particles in the two and three lepton final state at $\boldmath{\sqrt{s}=13\,}$TeV with the ATLAS detector

A search for the electroweak production of charginos, neutralinos and sleptons decaying to final states involving two or three electrons or muons is presented. The analysis is based on 36.1~fb$^{-1}$ of $\sqrt{s}$=13~TeV proton-proton collisions recorded by the ATLAS detector at the Large Hadron Collider. No significant deviations from the Standard Model expectation are observed and results are interpreted in a range of scenarios based on simplified models. Considered scenarios include the associated production of mass-degenerate next-to-lightest neutralino and lightest chargino, followed by their decays to final-state leptons and lightest neutralinos via either sleptons or Standard Model gauge bosons; direct production of chargino pairs, which in turn decay to leptons and lightest neutralinos via intermediate sleptons; and slepton pair production, where each slepton decays directly to the lightest neutralino and a lepton. Stringent limits at 95\% confidence level are placed on the masses of relevant supersymmetric particles in each of these scenarios.