Thesis (Ph.D.)--University of Washington, 2013A search for the decay of a light Higgs boson to a pair of weakly-interacting, long-lived particles in 20.8 fb-1 of proton-proton collisions at sqrt(s) = 8 TeV recorded in 2012 by the ATLAS detector is presented. The strategy requires that both of the long-lived particles decay just before or inside the hadronic calorimeter. No statistically significant excess of events is observed above the expected background and limits on the Higgs boson production and branching ratio to weakly-interacting, long-lived particles are derived as a function of the particle's proper decay length
