F2/EMC analysis how-to for shift takers Step 1

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Instructions for online analysis of F2/EMC Experiments (E12-10-002/E12-10-008)

1. We would like to keep the deadtime below 20 % so make sure to prescale accordingly before you start a run. That basically means to keep the DAQ target rate below 2000 Hz (look at the prescale gui that's in the DAQ VNC session.)


WARNING: THE PRESCALE GUI FREEZES AT TIMES, PLEASE MAKE SURE THAT IT UPDATES BY LOOKING AT IT FOR A WHILE. IF IT DOES NOT, RESTART. WHEN YOU CHANGE CONFIGURATION (BEAM CURRENT, KINEMATICS, TARGET) MAKE SURE TO PRESCALE SO THAT THE PRESCALED RATE IS NOT MUCH HIGHER THAN 2000 Hz


2. Once you accumulated 50 K CODA events (50000 CODA events): 

  for SHMS detector checks: ./run_shms.sh <run_number>

  for HMS detector checks: ./run_hms.sh <run_number>


--> This will bring up the online GUI for you to do detector sanity checks. Look carefully at all histograms and compare to the golden run which you can find in the binder.


--> It will also bring up an emacs window where you can check: current, trigger type, trigger and tracking efficiencies


As an example, this is what you would find in this emacs window:

Run #: 2081

BCM1 Current: 34.886 uA

BCM2 Current: 35.742 uA

BCM4a Current: 34.168 uA

Pre-Scale SHMS 3/4 : -1

Pre-Scale SHMS EL-Real : -1 --> this should be different than -1 (all the rest -1) when we take neg polarity runs

Pre-Scale SHMS EL-clean : 5 --> this should be different than -1 (all the rest -1) when we take pos polarity runs

Pre-Scaled Ps1 SHMS Computer Live Time : -0.6279 %

Pre-Scaled Ps2 SHMS Computer Live Time : -3.2613 % --> this should be larger than 80% if we take neg polarity runs

Pre-Scaled Ps3 SHMS Computer Live Time : 98.5311 % --> this should be larger than 80% if we take pos polarity runs

SING FID TRACK EFFIC  : 0.8380 +- 0.0097

E SING FID TRACK EFFIC  : 0.8417 +- 0.0100 --> this should be larger than 90% typically

Plane 1: 0.997916 --> this should be 99 % or higher

Plane 2: 0.996795 --> this should be 99 % or higher

Plane 3: 0.991199 --> this should be 99 % or higher

Plane 4: 0.976989

3_of_4 EFF : --> this should be larger than 99.5% typically


--> Once you close the emacs window another script will run without you doing anything. Watch what's printed on the screen at the end: this should give you an idea if the PID legs pedestals have drifted compared to the golden run. If they did, ** shout **. This would need to be fixed ASAP as it affects the efficiency of our PID-dependent trigger (remember: for production we run with ELREAL or ELCLEAN).


As an example, this is how it would look:


!!!!!!!!!!!!!!!!!Attention Needed IT AFFECTS TRIGGER EFFICIENCY!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

chan 2 bar 3 pNGCER Mean golden run: 134.5001 Mean current run: 116.7607 Mean diff: 17.7394

=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=
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