Operational experience with the CDF Run II silicon detector

The Collider Detector at Fermilab (CDF) Run II silicon detector is currently the largest operating silicon detector in High Energy Physics. Its 750,000 channels, spread over 6 m2 of p-on-n silicon sensors, and allow precision tracking of charged particles and vertexing at the 50μm level. The CDF Run II silicon detector is fundamental for all branches of the CDF physics program. It played a critical role in the discovery of BsBs mixing and is used extensively for the current Higgs boson searches at the forefront of the energy frontier. Over the last 6 years, the detector efficiency has remained stable above 95% after the Run II commissioning period. While originally designed to withstanding up to 3fb-1 of data, the CDF II silicon detector will have to last to the end of Run II where 5–8fb-1 of data are expected to be delivered. This letter presents the observed effects of infrastructure aging and the solutions implemented to prevent them, followed by the assessment on radiation damage and expected performance to the end of the Tevatron Run II program. The radiation aging of such a large scale system is particular relevant for future silicon detectors in hadronic colliders as LHC.