Dr Filippo Costa (CERN)
ALICE (A Large Ion Collider Experiment) is an experiment at the LHC (Large Hadron Collider) optimized for the study of heavy-ion collisions. The main aim of the experiment is to study the behavior of strongly interaction matter and quark gluon plasma. In order to be ready for the first real physics interaction, the 18 sub-detectors composing ALICE have been tested using cosmic rays and sequences of random trigger used to simulate p-p and heavy ion interactions. In order to simulate real triggers, the RTG (Random Trigger Generator) has been developed and it is able to provide 6 concurrent sequences of trigger with different probabilities. This paper will describe the hardware that generates the binary stream used as trigger and the software algorithms to create the sequences and to control the hardware. It will describe the tests performed in the laboratory on the random trigger generator to confirm its correct behavior and the details of the installation in the counting room of ALICE where it provides the triggers for all the sub-detectors. It will also discuss the configurations used to simulate several trigger combinations likely to happen with the real beam.