Photon Tagger Timing in PrimEx

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Photon Tagger Timing in PrimEx

• Nov. 18, 2005
• David Lawrence, JLab

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Photon Tagger
electron
electron
E-counters
T-counters
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Tagger time offsets vs. Run Number
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Tagger time offsets vs. Run Number
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Original Calibration run 5003
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• Calibration is done in two parts
• 1. Relative timing between tagger counters
• 2. Relative timing between detector systems

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Revised Calibration Run 5003
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E-T time difference for 50 runs (first file
only)Single set of calibration constants
(calibration history)
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Calibrated Trigger Bank
Raw Bank TAGT TAGE VETOT PST TACT TRIGT
Calibrated Bank TAGTHit TAGEHit VETOHit PSHit TACH
it
TAGM
HYCAL timing obtained from TRIGT with id9
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Trigger bit vs. Raw TDC
12 MOR HYCAL coin. 11 COSMIC 10 9 HYCAL
Sum 8 LMS 7 PS 6 pi0 5 Clock 4
TAC 3 MOR2 2 HYCAL 2clust. 1 MOR1
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Two banks were added
Trigger bit times (ns) shifted such that time
difference with TAGM is zero for hits
in coincidence
TRIGTHit
TRIGPHOTON
TAGM TRIGTHit coincidences for when TRIGTHit is
in-time with the ADC gate.
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Trigger Bit vs. TRIGPHOTON time (ns)
12 MOR HYCAL coin. 11 COSMIC 10 9 HYCAL
Sum 8 LMS 7 PS 6 pi0 5 Clock 4
TAC 3 MOR2 2 HYCAL 2clust. 1 MOR1
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Tagger HYCAL time difference (ns)for 50 runs
(first file)
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Tagger HYCAL time difference (ns)Run 5003
(first 2 files)
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Calibration constants added to database for
relative timing between tagger (as a whole) and
other detector systems

• SystemTAGGER Attributetagm2tac Size1
• SystemTAGGER Attributetagm2ps Size1
• SystemTAGGER Attributetagm2veto Size1
• SystemTAGGER Attributetagm2trig Size12

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Tagger TAC calibrated time difference (ns)
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Tagger VETO calibrated time difference (ns)
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Tagger PS calibrated time difference (ns)
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Summary

• Relative timing offsets for tagger counters were
  entered into the calibration database that cover
  the entire PrimEx run period
• Two new banks (TRIGTHIT, and TRIGPHOTON) were
  added to provide more consistency in forming
  HYCAL/Tagger coincidences
• Four new calibration attributes were added to
  provide a consistent way to form coincidences
  between the tagger and other detector systems.