More than half a million minimum-bias events of LHC collision data were collected by the ATLAS experiment in december 2009 at center-of-mass energies of 0.9 TeV and 2.36 TeV . This paper reports on studies of the initial performance of the ATLAS detector from these data . comparison between data and Monte Carlo predictions are shown for distributions of several track- and calorimeter-based quantities . The good performance of the ATLAS detector in these first data gives confidence for successful running at higher energies .

Performance of the ATLAS detector using first collision data

BERTIN, ANTONIO;BINDI, MARCELLO;CAFORIO, DAVIDE;DE CASTRO, STEFANO;DI SIPIO, RICCARDO;FABBRI, LAURA;