Abstract

A study was made of the flow of data and the simultaneous processing needed to reduce the 10/sup 7/ to 10/sup 8/ triggers per second expected at ISABELLE to a number of events on the order of 10 to 100 per second which would be written on magnetic tape. It was assumed that within 100 ns of the event a fast pretrigger would have reduced the data rate to at most 10/sup 7/ per second. At that point, data from all sense elements in the experiment would be fed into a 1-..mu..s-long pipeline. Within the first 1 ..mu..s (while the data are in the first pipeline) another level of triggering would reduce the trigger rate to at most 10/sup 6/ per second. The data would then be fed into a second pipeline which is 50 ..mu..s long. During the 50 ..mu..s the data are in the second pipeline, a more sophisticated level of triggering (slow trigger) would reduce the trigger rate to a level that can be handled by standard data processing techniques (microprocessors or larger machines), i.e., 10/sup 2/ to 10/sup 3/ per second. The pipelines and the buffer between them, a sequential address memory, are described first, andmore » then several alternative schemes for the pretrigger and slow trigger are presented. 10 figures.« le Document type: Report