A 40 MHz pipelined trigger for {Kappa}{sup 0} {r_arrow} 2{pi}{sup 0} decays for the CERN NA48 experiment

Journal Article · Sat Aug 01 00:00:00 EDT 1998 · IEEE Transactions on Nuclear Science

DOI:https://doi.org/10.1109/23.710934· OSTI ID:665238

Gorini, B; Avanzini, C ^[1]; Barr, G D ^[2]

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1. INFN, Pisa (Italy)
2. CERN, Geneva (Switzerland); and others

A first level trigger system based on a 40 MHz digital pipeline has been developed for the CERN NA48 experiment, aiming at measuring CP violation in K{sup 0} {r_arrow} 2{pi} decays. The outputs of the 13340 cells of the 10 m{sup 3} liquid krypton calorimeter are summed into 64 X and 64 Y projection strips and continuously digitized with 40 MHz FADCs. This information is used to reconstruct at each clock cycle and for the two calorimeter projections, the number of clusters, the impact time of each of them (with a precision of about 3 ns), their total energy and the first and second moments of the energy distribution. Based on the quantities listed above, a programmable look-up table system subsequently computes online the longitudinal position of the kaon decay vertex and performs an event selection. The system is described.

• OSTI ID: 665238
• Report Number(s): CONF-9709140-; ISSN 0018-9499; TRN: 98:011714
• Journal Information: IEEE Transactions on Nuclear Science, Vol. 45, Issue 4Pt1; Conference: 10. IEEE real time conference, Beaune (France), 22-26 Sep 1997; Other Information: PBD: Aug 1998
• Country of Publication: United States
• Language: English

Related Subjects

44 INSTRUMENTATION
INCLUDING NUCLEAR AND PARTICLE DETECTORS
43 PARTICLE ACCELERATORS
TRIGGER CIRCUITS
CP INVARIANCE
KAONS NEUTRAL
SHOWER COUNTERS
DIGITIZERS
PIONS NEUTRAL
READOUT SYSTEMS
DATA ACQUISITION SYSTEMS
WEAK HADRONIC DECAY
PION DETECTION