L1 Trigger for ACDC Jianchun (JC) Wang Syracuse University VELO ACDC Software Meeting 01/20/2006.
Published byModified over 6 years ago
Presentation on theme: "L1 Trigger for ACDC Jianchun (JC) Wang Syracuse University VELO ACDC Software Meeting 01/20/2006."— Presentation transcript:
L1 Trigger for ACDC Jianchun (JC) Wang Syracuse University VELO ACDC Software Meeting 01/20/2006
01/20/06Jianchun (JC) Wang2 L0 scintillation counter (prime trigger): Can be used either on straight through track (by moving counters) or on interaction. Rates can be varied by changing either hole size (2 available) or moving along beam. L1 software trigger: 1)Number of hits trigger: No requirements on alignment information. Requires stability and low noise. 2)Vertex (backup to number of hits trigger): No strong requirement on beam condition, less dependent on noise performance. Require alignment information, may bias the alignment study. Signal: interaction Bkg: straight-through Trigger for ACDC
01/20/06Jianchun (JC) Wang3 L0 Scintillation Trigger Trigger 1 = A 0 (A 1 A 2 ) (B 1 B 2 ) efficiency~90% Trigger 2 = A 0 ((A 1 B 2 ) (A 2 B 1 )) efficiency~60% B1B1 A2A2 A1A1 B2B2 A0A0 The scintillation counters are being constructed at Syracuse. Two pairs of B type with different sizes of hole (5 5cm 2 and 3 3cm 2 ) are made to incorporate beam size.
01/20/06Jianchun (JC) Wang4 Number of Hit Trigger (I) Requires that the sum of maximum number of R hits per station and maximum number of hits per station be at least 20. The noise level is about 0.1%. Only first 10 half stations are used. The selection efficiency is ~50%. Essentially no bkg is selected. It favors events with more tracks, which is consistent with our goal. It also keeps events with interaction happened at the last stations. signal bkg Signal selected Signal rejected
01/20/06Jianchun (JC) Wang5 Number of Hit Trigger (II) Requires that total number of hits of all 10 stations be at least 100. The noise level is about 0.1%. Only first 10 half stations are used. The selection efficiency is ~67%. No bkg is selected. It favors events with more tracks, and interactions happened at the beginning of the telescope. signal bkg Signal selected Signal rejected
01/20/06Jianchun (JC) Wang6 II. Total number of hits I. Nhit(R) max +Nhit() max More on Number of Hit Trigger The two triggers are correlated, although not fully. Both favor more tracks in the event. Currently I keep both in the trigger: 51% 67% = 71%. Noise simulation in MC might be too ideal. Different stations have different noise performance. A calibrated noise level will be subtracted. If the noise level is much higher than 0.1% we can use hits with higher pulse height for trigger only.
01/20/06Jianchun (JC) Wang7 Status Code runs under DaVinci as a normal analysis program. Need to modify the code to have trigger interface. The CPU time will be measured. More MC data may be needed.