Measurement of the electron reconstruction and identification efficiencies in ATLAS

Isolated, high-energy electrons constitute a very clean signature at hadron collider experiments. For final states of many Standard Model processes, as well as for physics beyond the Standard Model, electrons are key signature. A precise knowledge of the efficiency to correctly reconstruct and identify these electrons is thus important. In this contribution the measurement of these efficiencies is described. It is performed with a tag-and-probe method using $Z$ and $J/\psi$ decays to electrons in $pp$ collisions recorded in 2012 at $\sqrt{s}=8$~TeV, corresponding to an integrated luminosity of $L=20.3\,\mathrm{fb}^{-1}$. The combination of the measurements results in identification efficiencies determined with an accuracy of the order of one percent and better for electrons with a transverse energy of $E_{\mathrm{T}}>30$~GeV.