The CLEO-III trigger: axial and stereo tracking

The tracking subsystem of the CLEO-III Trigger consists of separate axial and stereo tracking pattern-matching modules, whose products are time-aligned and spatially correlated to provide pipelined trigger information every 42 ns with a latency of approximately 2 ns. This paper describes the pipelined signal processing and pattern recognition schemes used by the axial and stereo electronics to provide the information necessary to make trigger decisions. Extensive use of in-system field programmable gate arrays support path finding and timing information extraction.