Difference between revisions of "RescatteringPlan"

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#Start a parity DAQ run in production mode, take current to 2uA.  Raise HV for main detector PMTs and At PMTs by about 250 V (factor of 2^5~32) to get back near original signal size. Compare readout voltage to original (85uA) voltage to get within a factor of two (but less than 7V readout).
 
#Start a parity DAQ run in production mode, take current to 2uA.  Raise HV for main detector PMTs and At PMTs by about 250 V (factor of 2^5~32) to get back near original signal size. Compare readout voltage to original (85uA) voltage to get within a factor of two (but less than 7V readout).
 
# take another nominal (dp=0) run at these HV.  
 
# take another nominal (dp=0) run at these HV.  
−
# Change spectrometer setpoints to 1.25x nominal.  It is probably worth cycling the quads to get repeatible setpoints here.
+
# Change spectrometer setpoints to 1.35x nominal.  It is probably worth cycling the quads to get repeatible setpoints here.
 
#* raise MD and A_t PMT voltages by 250 more volts (do not exceed 2000V max).
 
#* raise MD and A_t PMT voltages by 250 more volts (do not exceed 2000V max).
 
#* Turn on S0 and S3 voltages.
 
#* Turn on S0 and S3 voltages.
Line 22: Line 22:
 
## Take another short (2-3min) parity run
 
## Take another short (2-3min) parity run
 
#Repeat the above for 1.01 and nominal setpoints, except now verify that
 
#Repeat the above for 1.01 and nominal setpoints, except now verify that
−
#* Scintillator, VDC, and GEM HV are all off. No need to run the integrating DAQ
+
#* Scintillator, VDC, and GEM HV are all off. No need to run the counting DAQ
 
#* Main Detector HV are in the original (+250V?) configuration.  If they have not been lowered yet, be sure to have a run at the same magnet settings with both HV settings.
 
#* Main Detector HV are in the original (+250V?) configuration.  If they have not been lowered yet, be sure to have a run at the same magnet settings with both HV settings.
 
# when back to nominal, test is complete.  Backout by returning MD HV to nominal.  
 
# when back to nominal, test is complete.  Backout by returning MD HV to nominal.  

Revision as of 08:18, 8 September 2019

Main :: Auxiliary Measurements

  1. L-HRS only. Integrating mode. All data taken with target lock at nominal, raster nominal, lead target.
  2. Start a parity DAQ run in production mode, take current to 2uA. Raise HV for main detector PMTs and At PMTs by about 250 V (factor of 2^5~32) to get back near original signal size. Compare readout voltage to original (85uA) voltage to get within a factor of two (but less than 7V readout).
  3. take another nominal (dp=0) run at these HV.
  4. Change spectrometer setpoints to 1.35x nominal. It is probably worth cycling the quads to get repeatible setpoints here.
    • raise MD and A_t PMT voltages by 250 more volts (do not exceed 2000V max).
    • Turn on S0 and S3 voltages.
    • Turn on VDC and GEM Voltages.
    1. Start counting mode daq with T1, T2, and T3 triggers
    2. Take a short (2-3min) parity run
    3. Turn the septum to nominal 333A. (no cycling is needed between septum setpoints)
    4. Take another short (2-3min) parity run
    5. end the counting mode run.
  5. Set next setpoint on the table, working down in dp from 1.25 through the 1.02 setpoint. For each step:
    1. check T1 trigger rate <600kHz. If more, turn off VDC voltage. If T1 trigger rate>2MHz, also turn off scintillator HV and GEM HV.
    2. Start an integrating run
    3. take a short (2-3 min) parity run.
      • if MD main detector voltage > 1 V, turn down to original (+250V) setpoint and repeat this run.
    4. Turn the septum to nominal 333A.
    5. Take another short (2-3min) parity run
  6. Repeat the above for 1.01 and nominal setpoints, except now verify that
    • Scintillator, VDC, and GEM HV are all off. No need to run the counting DAQ
    • Main Detector HV are in the original (+250V?) configuration. If they have not been lowered yet, be sure to have a run at the same magnet settings with both HV settings.
  7. when back to nominal, test is complete. Backout by returning MD HV to nominal.
setpoint .. septum ...... Q1 ........ Q2 ........ Q3  ........  Dipole ...	
............. [A] ....... [A] ....... [A] ....... [A] ...... [GeV] ..... [A] 						
.. 1 ........ 333 ..... 118.50 .... 407.70 .... 450.76 .... 0.95285 .. 318.79
.. 1.35 ... 449.55 .... 159.98 .... 550.40 .... 608.53 .... 1.28635 .. 430.37
.. 1.25 ... 416.25 .... 148.13 .... 509.63 .... 563.45 .... 1.19106 .. 398.49
.. 1.15 ... 382.95 .... 136.28 .... 468.86 .... 518.37 .... 1.09578 .. 366.61
.. 1.10 ... 366.30 .... 130.35 .... 448.47 .... 495.84 .... 1.04814 .. 350.67
.. 1.07 ... 356.31 .... 126.80 .... 436.24 .... 482.31 .... 1.01955 .. 341.11
.. 1.04 ... 346.32 .... 123.24 .... 424.01 .... 468.79 .... 0.99096 .. 331.54
.. 1.02 ... 339.66 .... 120.87 .... 415.85 .... 459.78 .... 0.97191 .. 325.17
.. 1.01 ... 336.33 .... 119.69 .... 411.78 .... 455.27 .... 0.96238 .. 321.98
.. 1 ........ 333 ..... 118.50 .... 407.70 .... 450.76 .... 0.95285 .. 318.79
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