Search for direct top squark pair production in the 3-body decay mode with one lepton final states in √s=13 TeV pp collisions with the ATLAS detector

Natural supersymmetry suggests a light top squark ( t̃ 1 ), possibly within the discovery reach of Run-2 of the LHC. This poster presents the latest result of an analysis targeting a compressed region of the stop phase space where the mass difference between the stop and the lightest neutralino ( χ̃ 01 ) is smaller than the top-quark mass, using pp collision data collected over the full Run-2 of the LHC. A machine learning technique was employed in the analysis to improve the discrimination of signals from backgrounds dominated by the tt̄ process.