Radiation damage studies and lifetime estimates for the CDFII silicon detector

The CDFII silicon detector system operates in a severe radiation environment as it measures the products of high energy proton–antiproton interactions provided by the Tevatron Run II accelerator. This article describes the manifestation of radiation damage to the detectorʹs silicon sensors in two ways: the evolution of sensor depletion voltages toward a maximum value, and the degradation of the signal-to-noise ratios for charge clusters read out by the detector. In both cases we use data collected through 1.8 fb - 1 of integrated luminosity to determine the detectorʹs ability to perform for the lifetime of the Tevatron Run II, expected to be 5 – 8 fb - 1 of integrated luminosity.