Combination of searches for invisible Higgs boson Decays with the ATLAS experiment

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, Z(ℓℓ))H, and W / Z (had) H, all performed with the ATLAS detector using 36.1 fb⁻¹ of pp collisions at a center-of-mass energy of √s=13 TeV at the LHC. In combination with the results at √s=7and 8 TeV, an exclusion limit on the H→invisible branching ratio of 0.26 (0.17^+0.07_−0.05) at 95% confidence level is observed (expected).