The ATLAS discovery potential for the channel ttH, H to bb

The production of a light Standard Model Higgs boson in association with a top quark-pair at the LHC is studied with the fast simulation of the ATLAS detector. The Higgs boson is assumed to decay into bbbar, one top-quark to decay into lnub and the other top-quark into jjb, leading to a complex final state of 1 isolated lepton, missing transverse momentum, and 6 jets of which 4 jets are b-jets. The full reconstruction of the final state is necessary to minimize the combinatorial background from assigning two out of the four b-jets to the Higgs boson decay and to discriminate the signal process from the large background from top quark-pairs with additional jets. Two methods for the analysis of this channel are presented: A `classical' reconstruction which is based on the procedure developed in the context of the ATLAS detector and physics performance TDR, and an improved method which makes use of likelihood techniques.