Title :
The multi-level trigger system of the HADES detector
Author :
Traxler, M. ; Becker, R. ; Fröhlich, I. ; Kühn, W. ; Lehnert, J. ; Lichtblau, C. ; Lins, E. ; Petri, M. ; Pleier, M.-A. ; Ritman, J.
Author_Institution :
II. Phys. Inst., Giessen Univ., Germany
Abstract :
The multi-level trigger system of the HADES detector is intended to select dilepton events in heavy ion reactions and to reduce minimum bias event rates by a factor of 10 000. After a first level trigger based on the charged particle multiplicity the second level is the essential dilepton trigger which identifies electron signatures in several detector components and correlates them to dileptons. The third level trigger verifies these dilepton candidates using additional tracking information. Programmable logic devices, FPGAs and CPLDs, as well as DSPs are widely used to gain flexibility and provide common solutions. The trigger concept and fully functional versions of the readout boards and the second level trigger are presented
Keywords :
Cherenkov counters; electron detection; electron spectrometers; field programmable gate arrays; nuclear electronics; programmable logic devices; trigger circuits; CPLDs; FPGAs; HADES detector; additional tracking information; charged particle multiplicity; dilepton events; dilepton trigger; electron signatures; first level trigger; fully functional versions; heavy ion reactions; minimum bias event rates; multi-level trigger system; programmable logic devices; readout boards; third level trigger; trigger concept; Detectors; Electromagnetic measurements; Electrons; Event detection; Mesons; Sensor arrays; Spectroscopy; Superconducting magnets; Synthetic aperture sonar; Time measurement;
Conference_Titel :
Real Time Conference, 1999. Santa Fe 1999. 11th IEEE NPSS
Conference_Location :
Sante Fe, NM
Print_ISBN :
0-7803-5463-X
DOI :
10.1109/RTCON.1999.842689
