Improved luminosity determination in pp collisions at √s = 7 TeV using the ATLAS detector at the LHC. European Physical Journal C Volume 73, Issue 8, August 2013, Pages 1-39

The luminosity calibration for the ATLAS detector at the LHC during pp collisions at √s = 7 TeV in 2010 and 2011 is presented. Evaluation of the luminosity scale is performed using several luminosity-sensitive detectors, and comparisons are made of the long-term stability and accuracy of this calibration applied to the pp collisions at √s = 7 TeV. A luminosity uncertainty of δL/L = ±3.5% is obtained for the 47 pb-1 of data delivered to ATLAS in 2010, and an uncertainty of δL/L = ±1.8% is obtained for the 5.5 fb-1 delivered in 2011.