Measurements of Sensor Radiation Damage in the ATLAS Inner Detector using Leakage Currents

Non-ionizing energy loss causes bulk damage to the silicon sensors of the ATLAS pixel and strip detectors.This damage has important implications for data-taking operations, charged-particle track reconstruction, detector simulations, and physics analysis. This talk presents simulations and measurements of the leakage current for the ATLAS pixel detector as a function of location in the detector and time, using data collected in Run 1 (2010-2012) and Run 2 (2015-2018) of the Large Hadron Collider. The extracted fluence shows a much stronger |z|-dependence in the innermost layers compared to calculations. Furthermore, the overall fluence is significantly higher on the second innermost layer with an increasing agreement with calculations at higher radii. These measurements are an important validation of the simulation models and can be used in part to justify safety factors for future detector designs and interventions.