Searches for supersymmetric higgsinos with the ATLAS detector

A search for supersymmetric partners of the Higgs and gauge bosons (charginos and neutralinos) is presented, using data collected by the ATLAS experiment at the LHC. Considerations on the naturalness of the Higgs boson mass suggest that the two lightest neutralinos might be a mix of the partners of the Higgs, and could have a similar mass. Using this scenario as reference, the analysis selects events in final states with pairs of low transverse momentum electrons and muons, stemming from the decay of the two lightest neutralinos. Furthermore, high missing transverse momentum generated by the lightest neutralinos, which are non detectable, and an energetic jet coming from QCD initial state radiation. The results obtained in the latest analysis are shown, including the limits assigned on the mass parameters of the higgsinos.