Simulation and hit reconstruction of irradiated pixel sensors for the CMS experiment

In this paper a detailed simulation of irradiated pixel sensors was used to investigate the effects of radiation damage on the position determination and optimize the hit reconstruction algorithms. The simulation implements a model of radiation damage by including two defect levels with opposite charge states and trapping of charge carriers. The simulation shows that a position resolution below 15 μμm along the CMS rr–φφ plane can be achieved after an irradiation fluence of 5.9×1014neq/cm2. In addition, we show that systematic errors in the position determination can be largely reduced by applying ηη corrections.