Boosting Invisible Searches Via Zh: From The Higgs Boson To Dark Matter Simplified Modelsy

Higgs boson production in association with a Z boson at the LHC is analyzed, both in the Standard Model and in simplified model extensions for dark matter. We focus on H -> invisibles searches and show that loop-induced components for both the signal and background present phenomenologically relevant contributions to the BR (H -> inv) limits. We also show how multijet merging improves the description of key distributions to this analysis. In addition, the constraining power of this channel to simplified models for dark matter with scalar and pseudoscalar mediators phi and A is discussed and compared with noncollider constraints. We find that with 100 fb(-1) of LHC data, this channel provides competitive constraints to the noncollider bounds, for most of the parameter space we consider, bounding the universal Standard Model fermion-mediator strength at g(v) < 1 for moderate masses in the range of 100 GeV < m(phi/A) < 400 GeV.