Global Trigger and Global Muon Trigger Manfred Jeitler and Ivan Mikulec Trigger Meeting 19 September 2006

GT tests with DT muons tested the chain DTTF  GMT  GTL  FDL  TCS L1AOUT TTCci  DTTF with cosmic muons Drift Tube Track Finder  Global Muon Trigger  Global Trigger Logic Board  Final Decision Logic  Trigger Control System  L1A Output board  TTCci  Drift Tube Track Finder GTL and DTTF read out with “spy” readout GTFE (Global Trigger Front End): readout board for Global Trigger not yet available limited trigger rate (deadtime), but otherwise full system test trigger data from GTL and DTTF are the same trigger conditions correctly reflected in the data

DTTF DTTF-GMT-GT test GMT TCS FDL GTL GT crate cosmic muons TTCci L1AOUT TCS FDL GTL DTTF cosmic muons L1A TTCci L1A spy readout spy readout

with different pt thresholds L1Accept rate per pt bin  comparing 3 runs taken with different pt thresholds no errors (values with pt=0 due to software error in memory address wrapping - understood)

time between subsequent events for three different pt thresholds get L1A rate  from slope of exponential decay get deadtime from dead = trun / Nevents (total time of run over number of events taken) deadtime independent of trigger rate deadtime due to “spy” readout 

the question of the clock distribution the idea of the TTC group: get L1As, BGOs and clock from L1AOUT into TTCci “so there should be no danger of clock shifting with respect to L1A and BGO signals” TTCci sends this to TTCex, which gets directly the “best possible” clock from TTCmi (or its successor) detectors need by all means this direct TTCmi clock because the TCS system could introduce a slow drift of up to 2 ns but: we really do not expect the clock to shift into the wrong bunch crossing if this should ever happen, the Global Trigger would notice it right away in its monitoring but the clock from the TCS may also have a jitter (on top of a drift) the TCS was never meant by its designers to distribute a clock ! so why use this clock at all? please use TTCmi clock right away in TTCci !

clock distribution TCS TIM TTCmi clock GT crate clock + orbit L1AOUT TCS TIM TTCmi clock + orbit L1A + BGO (+ clock) clock TTCci L1A, BGOs, clock TTCex

plans test with other muon systems start testing with RCT RPC: could also use “Technical” trigger if RPC-GMT connection is not ready in time CSC: using “Technical” trigger would need a bit of work on signal levels of course it would be best to test everything with the final setup start testing with RCT debug trigger path before MT/CC 2 starts test and run with final readout board (GTFE) as soon as it is available start debugging our readout with LTC triggers switch to use GT for “production” as soon as everything works