Higgs Boson to Invisible searches with the ATLAS Detector in Run 2*

The total decay width of the Higgs boson under SM assumptions hasn’t been constrained precisely and allows for a branching fraction as large as O(30%) where the Higgs decays into invisible particles, such as dark matter particles. This talk will include the searches for invisible decays of the Higgs produced in three production modes using data, corresponding to an integrated luminosity of 36.1 fb-1, of the proton-proton collisions at a center-of-mass energy of 13 TeV with the ATLAS detector. Particular emphasis will be placed on the Vector Boson Fusion (VBF) production mode, which drives the sensitivity thus far. I will talk about the analysis techniques, leading constraints on sensitivity and resulting limits on the invisible branching fraction. The results of combining the production modes using data from Run 1 and Run 2 and projections for HL-LHC will also be presented. The Higgs to invisible branching fraction will be interpreted in the context of Higgs portal dark matter models and compared to direct dark matter searches.