The "neutral" trigger system for the selection of K-o --> 2 pi(o) --> 4 gamma decays of the NA48 CP-violation experiment is described. The trigger system has been implemented in a 40 MHz "dead-time free" pipeline to allow large rate reduction and high-trigger efficiency. The trigger decision is based on the information from 13340 cells of the electro-magnetic calorimeter. Every 25 ns the energy, the centre of gravity, the kaon lifetime and the number of peaks in calorimeter projections are calculated in the trigger. The pipeline system is described and the performance of the trigger during the 1997 data-taking period is discussed. (C) 1998 Published by Elsevier Science B.V. All rights reserved.
A 40 MHz-pipelined trigger for K-0 -> 2 pi(0) decays for the CERN NA48 experiment
COSTANTINI, FLAVIO;SOZZI, MARCO STANISLAO;
1998-01-01
Abstract
The "neutral" trigger system for the selection of K-o --> 2 pi(o) --> 4 gamma decays of the NA48 CP-violation experiment is described. The trigger system has been implemented in a 40 MHz "dead-time free" pipeline to allow large rate reduction and high-trigger efficiency. The trigger decision is based on the information from 13340 cells of the electro-magnetic calorimeter. Every 25 ns the energy, the centre of gravity, the kaon lifetime and the number of peaks in calorimeter projections are calculated in the trigger. The pipeline system is described and the performance of the trigger during the 1997 data-taking period is discussed. (C) 1998 Published by Elsevier Science B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.