Trigger Study for KM3Net-Italia

Abstract

A new trigger for NEMO Phase 2 tower based on the time differences of the PMT hits has been studied. Such a trigger uses only a fixed number of PMT hits in a chosen time windows. The background trigger rate is drastically reduced requiring hits from different PMTs. A 87% trigger efficiency was estimated by Montecarlo simulation for muon tracks with at least 5 PMT hits. The trigger rate estimated by Montecarlo was also measured on raw data. The results from Montecarlo simulations and raw data are reported.