1. 9/23/2005 Inst. Ana. MeetingTKR trigger efficiency with ACD&CAL 1 Study of TKR trigger efficiency with ACD and CAL Mutsumi Sugizaki, Hiro Tajima SLAC

2. 9/23/2005 Inst. Ana. MeetingTKR trigger efficiency with ACD&CAL 2 Objective and Method Measure TKR trigger efficiency in a way free from the TKR data –TKR trigger efficiencies were estimated from data of TKR itself, so far. An unbiased measurement free from TKR is important. –Any kinds of TKR data are influenced by the data latch timing, which causes inconsistency among read-out strip data, trigger primitive, and trigger request. It is another difficulty to measure the TKR trigger efficiency. We cannot latch trigger primitive at the optimum timing. It also requires special data taking. Use ACD and CAL trigger to estimate the TKR efficiency –Measure the TKR trigger probability when there are triggers on ACD-ACD / ACD-CAL, then compare it with that expected from the Monte Carlo simulation.

3. 9/23/2005 Inst. Ana. MeetingTKR trigger efficiency with ACD&CAL 3 Measurement with ACD-ACD trigger Event selection condition on SVAC ntuple –AcdLowDisc[tileID1]>0 and AcdLowDisc[tileID2]>0 Validation check by 8-Tower 2M surface muon MC data Tower #0 Tower #4 Tower #8 Tower #12 000010020030040 220 220-000220-010 220-020 220-030

4. 9/23/2005 Inst. Ana. MeetingTKR trigger efficiency with ACD&CAL 4 Measurement with ACD-CAL trigger Event selection condition on SVAC ntuple –AcdLowDisc[tileID1]>0 and CalXtalEne[TowerD][layer=0][any_column][any_end]>20MeV Validation check by 8-Tower 2M surface muon MC data Tower #0 CAL #0 Tower #4 Tower #8 Tower #12 000010020030040 CAL#0-000CAL#0-010 CAL#0-020 CAL#0-030

5. 9/23/2005 Inst. Ana. MeetingTKR trigger efficiency with ACD&CAL 5 Future Plan Investigate the dependence on the trigger condition and the event-selection parameters –CAL-Low threshold level 20 MeV or 100 MeV –Trigger combination Base: ACD-top && (ACD-side || CAL) Is more complicated trigger condition nessary? –Which combinations of ACD-ACD/ACD-CAL are available for this analysis out of hundreds of these combinations? Compare these MC expectations with real data. –TKR trigger –Event rate Consider valid trigger conditions and event selections for in-orbit calibration

6. 9/23/2005 Inst. Ana. MeetingTKR trigger efficiency with ACD&CAL 6 Summary A method to measure TKR trigger efficiency with ACD and CAL, which is free from the TKR data, is investigated. It is confirmed to work well. More detailed study about trigger condition and event selection criteria is necessary to use it for on-orbit calibration. We will apply it to real data immediately when data taken with ACD is available.