Summary of non-resonant and resonant Higgs boson pair searches from the ATLAS experiment

This note presents a summary of results from the most recent ATLAS Higgs boson pair ($HH$) searches. Overlays of 95\% confidence level upper limits are presented for the ratio of non-resonant $HH$ production cross-section to the Standard Model prediction and for the resonant $HH$ production cross-section as a function of the mass of a narrow width scalar resonance. The inputs to these summary figures are from searches using proton-proton collisions at $\sqrt{s} = 13$~TeV, with both partial and full Run 2 datasets.