SM Higgs boson searches in the early ATLAS data

ATLAS exclusion and discovery potentials of Standard Model Higgs boson searches at the LHC at 14 TeV, 10 TeV and 7 TeV center-of-mass energy are reviewed. For the total LHC energy of 7 TeV and the integrated luminosity of 1 $fb^{-1}$, contributions from important decay channels $H \rightarrow WW^{*} \rightarrow l\nu l\nu, H \rightarrow ZZ^{*} \rightarrow llll$ and $H \rightarrow \gamma\gamma$ are considered, based mostly on recent full Monte-Carlo simulations. First measurements of backgrounds to SM Higgs production are also presented.