Abstract
Dark matter particles, if sufficiently light, may be produced in decays of the Higgs boson. This Letter presents a statistical combination of searches for H ! invisible decays where H is produced according to the Standard Model via vector boson fusion, Z¹``ºH, and WZ¹hadºH, all performed with the ATLAS detector using 36.1 fb1 of pp collisions at a center-of-mass energy of p s = 13 TeV at the LHC. In combination with the results at p s = 7 and 8 TeV, an exclusion limit on the H ! invisible branching ratio of 0:26 ¹0:17+0:07 0:05º at 95% confidence level is observed (expected).