Here are some thoughts on the plan for taking data with the tagger during the last shift
of "electron beam" commissioning. Here is a proposed plan discussed by Elton Smith, Luc
Murphy, Dave Doughty and Steve Barrow and Hall Crannell:
General Setup:
Tagger Magnet ON (Current setting for 4 GeV = 1366A)
Radiator IN (10**-6)
Target IN (Saclay H target filled)
Readout: TOF and Tagger crates required. (Note: Including ADCs with beamline devices).
Readout: Other CLAS systems desirable.
0. Tune photon beam with 4 GeV electrons.
1. Trun on sellected E and all T counter HV's.
2. Look at the three E-counter pmt signals (available in counting house) and do gain
matching "by eye" on the scope.
Vary HV to understand voltage dependence of signal.
Check E-T counter timing using T1 signal.
Also look at signals on a long time scale to roughly monitor accelerator duty cycle.
3. Check Timing in the data.
Setup Trigger using Steve's configuration file (before PRESTART)
A) Trigger (Trigger Supervisor Input=1) : Level 1
(File = MinDEDX_TOF_ECALlow_Sect123456.trg)
B) Trigger (Trigger Supervisor Input=1) : Tagger (asynch input)
* Level 1 (Trigger file = MinDEDX_TOF_ECALlow_Asynch_Sect123456.trg)
C) Trigger (Trigger Supervisor Input=8, Low intensity, Prescale factor as required) :
Tagger only
Take ~ 50K triggers of A, B, and C. Then take ~200K triggers with B.
I expect to be available for the first half of the shift.
Cheers, Elton.