Search for charginos and neutralinos in final states with two boosted hadronically decaying bosons and missing transverse momentum in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

A search for electroweakinos at the Large Hadron Collider is reported using fully hadronic final states and missing transverse momentum. Pair-produced electroweakinos are explored each decaying into a high-$p_{\text{T}}$ Standard Model gauge boson or a Higgs boson. Fully-hadronic final states are studied to exploit the advantage of the large branching ratio, and the efficient background rejection by identifying the high-$p_{\text{T}}$ bosons using the large-radius jets and jet substructure information. An integrated luminosity of 139 fb$^{-1}$ of proton-proton collision data collected by the ATLAS detector at a center-of-mass energy of $\sqrt{s}=13$ TeV is used. No significant excess is found beyond the Standard Model expectation. The 95% confidence level exclusion limits are set on wino or higgsino production with various assumptions in the decay branching ratios and the type of the lightest SUSY particle. A wino (higgsino) mass up to 1060 (900) GeV is excluded when the lightest SUSY particle mass is below 400 (240) GeV.