A modular PC based silicon microstrip beam telescope with high speed data acquisition

Abstract A PC based high speed silicon microstrip beam telescope consisting of several independent modules is presented. Every module contains an AC-coupled double sided silicon microstrip sensor and a complete set of analog and digital signal processing electronics. A digital bus connects the modules with the data acquisition (DAQ) PC. A trigger logic unit coordinates the operation of all modules of the telescope. The system architecture allows easy integration of any kind of device under test into the DAQ chain. Signal digitization, pedestal correction, hit detection and zero suppression are done by hardware inside the modules, so that the amount of data per event is reduced by a factor of 80 compared to conventional readout systems. In combination with a two level DAQ scheme, this allows event rates up to 7.6 kHz . This is a factor of 40 faster than conventional VME based beam telescopes while comparable analog performance is maintained, achieving signal to noise ratios of up to 70:1. The telescope has been tested in the SPS testbeam at CERN. It has been adopted as the reference instrument for testbeam studies for the ATLAS pixel detector development.