Search for direct top squark pair production in final states with two leptons in $\sqrt{s}$ = 8 TeV pp collisions using $20$fb$^{-1}$ of ATLAS data.

The results of a search for direct pair production of supersymmetric partners of the top quark are reported using 20.3 \ifb\ of integrated luminosity from LHC $pp$ collisions at 8~\TeV\ collected by the ATLAS detector. Top squarks are searched for in events with two leptons in the final state. No excess above the Standard Model expectation is observed. Exclusion limits at 95\% confidence level are placed on the mass of a top squark decaying as $\tone \rightarrow \chinoonepm b \rightarrow \ninoone W^{(*)} b$, for several assumptions on the hierarchy of the chargino $\chinoonepm$ and the lightest neutralino masses. Additionally, exclusion limits are placed for the first time on the mass of a top squark decaying directly into $W b \ninoone$.