Test-beam results from the ATLAS level-1 calorimeter trigger demonstrator

Abstract

The ATLAS level-1 calorimeter trigger will utilise a number of advanced technologies, many of which have already been successfully demonstrated. To evaluate the different technologies associated with the important areas of high-speed data transport a large demonstrator system has been designed and operated during the last two years, using signals from prototype calorimeters in the ATLAS test-beam. Using this system, inter-crate data transmission and reception have been demonstrated at over 1.4 Gbyte/s, with individual links running at up to 1.6 Gbaud. Operating with 160 Mbit/s signals across a transmission-line backplane, custom transceiver ASICs have achieved inter-module data fanout at peak rates above 800 Mbyte/s. With the addition of further modules, the system was extended to emulate a vertical slice through the ATLAS level-1 calorimeter trigger. We present here the results from these tests, including measurements of bit-error rates across different data paths.