Speaker
Description
Supersymmetry is a promising extension of the Standard Model of Particle Physics (SM) as it provides a solution to some of the open questions of the SM. If squarks and gluinos are beyond the reach of the LHC, the production of charginos and neutralinos could be the dominant production mode of supersymmetric particles in sqrt(s)=13 TeV proton-proton collisions at the LHC. A search for electroweak production of supersymmetric particles, using 139 fb−1 of proton-proton collisions recorded from 2015 to 2018 by the ATLAS detector, is presented. In the signal scenario considered, a chargino χ̃±1 is produced together with a next-to-lightest neutralino χ̃02. The chargino decays via χ̃±1 → W±χ̃02 while the neutralino decays through χ̃02 → hχ̃02. The final state of this signal scenario can thus in many cases be characterised by the presence of two b-jets from the Higgs decay, missing transverse momentum and exactly one lepton from W± → l±ν, providing high discrimination against SM background. In this work, the analysis strategy is introduced, exploiting the varying shapes of signal and background distributions in a two-dimensional shape fit and estimating the SM background through semi-data-driven techniques. Finally, the results of the search are presented and discussed.
