A Search for Non-Standard Model Higgs Bosons Produced in Association with b-Quarks at the ATLAS Experiment

With the discovery of a Standard-Model-like Higgs boson at the LHC in 2012, the particle content of the Standard Model has been fully verified experimentally, and the focus turns even more fully to searches for physics beyond the Standard Model. One interesting class of theories, supersymmetry, predicts (at least) 4 additional Higgs bosons. This is a search for two of those SUSY Higgs particles, A0 and H0, in production states including additional b-quarks and in final states where A0 and H0 are decaying to a b-bbar final state. Using data-driven estimations to understand and model the large multi-b-quark QCD backgrounds at the LHC, we set limits on the production cross section times b-bbar branching ratio of 1.79-0.25 pb in the range 450 GeV < mA0 < 800 GeV. No statistically significant excess is observed in the data relative to the background-only expectations. This is the first resonance search in this final state at ATLAS, and the highest-mass search for A0 and H0 decaying to b-bbar that has yet been performed.