A 40-GBYTE S READ-OUT SYSTEM FOR LARGE COLLIDER DETECTORS/

We present the design of a read-out system for a large collider detect or. The readout was designed for GEM, one of the two detectors that wa s planned for the Superconducting Super Collider. However, given the s imilarity in requirements, the design may be relevant for other proton collider detectors. The readout is designed to cope with the huge num ber of channels and enormous data rates, typical for high luminosity c olliders. To simplify front-end design, the system reads all digitized data from the detector data sources at the full Level 1 trigger rate of up to 100 kHz. A total read-out bandwidth of 40 GBytes/s is availab le. Data are stored in buffers that are accessible for further event f iltering by an on-line processor farm. Data are transported to the far m only as they are needed by the higher-level trigger algorithms, lead ing to a reduced bandwidth requirement in the data acquisition system.