2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 | 2014 | 2013 | 2012 | 2011 | 2010 | 2009 | 2008

Interactions between trigger and detector on CPLEAR

Authors: CPLEAR Collaboration (including E. van Beveren)

Ref.: prepared for the 4th Conference on the "Intersections between particle and nuclear physics", Tucson, Arizona, 24-29 May 1991, published in AIP Conference Proceedings 243, 408-414 (1992)

Abstract: CPLEAR is specified to run with a rate of 2 million antiproton annihilations/second, from which K0+cc events are selected at the level of 0.5%. The detectors were built to achieve three aims; to function at high rate, to present minimum interference with the K0 physics and to work closely with the trigger selecting, on line, events of interest. A large burden of this fell to the central tracking chambers, discussed here, which present the trigger with tracking information within 300ns. Spatial information for up to 9 points per track is available, on line, to a precision of 300µm at over 97% efficiency. The trigger, also discussed, was designed to select very specific physics processes among the annihilation channels while minimizing dead time. A cascade of trigger decisions is made on time scales of 60ns to 25µs working with information from the tracking chambers and calorimeter. This allows bad events to be abandoned quickly. Within the trigger processing time events are fully reconstructed including; charged & neutral particle reconstruction and identification. To achieve this a series of modular custom built processors are used with pipelines and point to point parallel busses. Detectors and trigger work closely. The detectors are segmented to conform easily to the trigger electronics (32 or 64 segments) and work with the same bus protocols.

DOI: 10.1063/1.41464

URL: link.aip.org