The Backward Silicon Track Trigger of the HERA Experiment H1

The Backward Silicon Tracker of the H1 experiment is being used in conjunction with a lead-fiber Calorimeter for detailed investigations of inclusive deeply inelastic scattering of leptons from protons, e±P → e±X, and of charm production at small values of the Bjorken variable x, x ≤ 10−3. In this thesis the development of a trigger for the Backward Silicon Tracker is described. The detector was installed in 2001 and started to operate in H1 after the HERA upgrade. Exploiting the low noise performance and fast time response of solid state semiconductors, a silicon pad detector telescope was developed for the first level trigger on tracks scattered in the backward region of the H1 detector. The design of the new trigger part of the BST consisting of silicon pad detectors and dedicated fast readout circuitry is described. Results of beam tests and first luminosity data are presented.