Early physics reach of the ATLAS detector

The first year of data taking at ATLAS should be a very challenging and rewarding time. It will include commissioning of the detector and many interesting physics results. The commissioning of the detector components will mainly rely on physics signals. The staging of some subdetectors will influence the B physics program and result in slightly reduced significances in most physics analyses. The searches for Higgs bosons and supersymmetric particles have been studied in great detail. If a Higgs boson from the Standard Model exists, it will be discovered within the first year. If supersymmetry exists the discovery of at least one light Higgs boson as well as some supersymmetric particles is very probable within the first year of the LHC. PACS: 25.70.Ef – 21.60.Gx – 27.30.+