Performance of the ATLAS detector using first collision data
Journal of High Energy Physics 2010:9 (2010)
Abstract:
More than half a million minimum-bias events of LHC collision data were collected by the ATLAS experiment in December 2009 at centre-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. Comparisons 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 CMS Level-1 trigger during commissioning with cosmic ray muons and LHC beams
Journal of Instrumentation 5:3 (2010)
Abstract:
The CMS Level-1 trigger was used to select cosmic ray muons and LHC beam events during data-taking runs in 2008, and to estimate the level of detector noise. This paper describes the trigger components used, the algorithms that were executed, and the trigger synchronisation. Using data from extended cosmic ray runs, the muon, electron/photon, and jet triggers have been validated, and their performance evaluated. Efficiencies were found to be high, resolutions were found to be good, and rates as expected. © 2010 IOP Publishing Ltd and SISSA.Performance of the CMS cathode strip chambers with cosmic rays
Journal of Instrumentation 5:3 (2010)
Abstract:
The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47μm to 243μm. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns. © 2010 IOP Publishing Ltd and SISSA.Performance of the CMS hadron calorimeter with cosmic ray muons and LHC beam data
Journal of Instrumentation 5:3 (2010)
Abstract:
The CMS Hadron Calorimeter in the barrel, endcap and forward regions is fully commissioned. Cosmic ray data were taken with and without magnetic field at the surface hall and after installation in the experimental hall, hundred meters underground. Various measurements were also performed during the few days of beam in the LHC in September 2008. Calibration parameters were extracted, and the energy response of the HCAL determined from test beam data has been checked. © 2010 IOP Publishing Ltd and SISSA.Performance of the CMS drift-tube chamber local trigger with cosmic rays
Journal of Instrumentation 5:3 (2010)