Title	A Fast, First Level, RØ, Hardware Trigger for the DØ Central Fiber Tracker using Field Programmable Gate Arrays
	1996 IEEE Nuclear Science Symposium, Vol. 1, 307-10 (ISSN: 1082 - 3654)
Authors	B. Abbot, B. Angstadt, F. Borcherding, M. Johnson, M.I. Martin
Abstract	We have developed an RØ trigger using eight doublet layers of axial fibers in the new Central Fiber Tracker for the DØ Upgrade Detector at Fermilab. This trigger must be formed in less than 500 ns and distributed to other parts of the detector for a level 1 trigger decision. The high speed is achieved by using massive parallel AND/OR logic instanced in state-of-the-art field programmable gate arrays, FPGAs. The programability of the FPGAs allows corrections to the track roads for the as-built detector and for dinamically changing the transverse momentum threshold. To reduce the number of fake tracks at high luminosity the narrowest possible roads must be used which pushes the total number of roads into the thousands. Monte Carlo simulations of the track trigger have been run to develop the trigger algorithms and a vendor supplied simulator has been used to develop and test the FPGA programming.
	Work supported by the U.S. Department of Energy under contract No. DE-AC02-76CHO3000