  A search for the decay of a light Higgs (120 - 140 GeV) to a pair of weakly-interacting, long-lived particles in 1.94 fb^-1 of proton-proton collisions at sqrt{s} = 7 TeV recorded in 2011 by the ATLAS detector is presented. The search strategy requires that both long-lived particles decay inside the muon spectrometer. No excess of events is observed above the expected background and limits on the Higgs boson production times branching ratio to weakly-interacting, long-lived particles are derived as a function of the particle proper decay length. 
Search for a light Higgs boson decaying to long-lived weakly-interacting   particles in proton-proton collisions at sqrt(s) = 7 TeV with the ATLAS   detector