Silicon tracking in CMS

An overview of the tracking detectors of the CMS experiments at the LHC is presented. The CMS tracking system features an all-silicon layout consisting of a pixel and a silicon micro-strip detector. These detectors are designed to operate with 40 MHz bunch crossing frequency in a high particle flux density and extreme radiation environment. As well as satisfying the requirements for off-line data analysis, the CMS tracking provides a robust partial reconstruction using the absolute minimum number of reconstruction steps inside a region of interest, tuned according to the specific benchmark channel. Recent results have shown that the performances of the partial reconstruction in terms of resolution and CPU time allows the use of the Tracker at the first stage of the high level trigger on all physics event streams. (10 refs).