UC Santa Cruz

Many of the interesting physics processes to be measured at the LHC have a signature involving one or more isolated electrons. The electron reconstruction and identification efficiencies of the ATLAS detector at the LHC have been evaluated using proton–proton collision data collected in 2011 at s=7$$\sqrt{s}= 7$$ TeV and corresponding to an integrated luminosity of 4.7 fb-1$$^{-1}$$. Tag-and-probe methods using events with leptonic decays of W$$W$$ and Z$$Z$$ bosons and J/ψ$$J/\psi $$ mesons are employed to benchmark these performance parameters. The combination of all measurements results in identification efficiencies determined with an accuracy at the few per mil level for electron transverse energy greater than 30 GeV.