High-Low Ratios

V. Ikonnikov 2002
Revised and amended by A. Kazantsev 12.2003
stkav@rcf.rhic.bnl.gov
High-low ratio extraction code.
This program scans through all events, and first finds maximum value of high gain for each channel and steps down for 100 channels (hg_max). Below this value dependence of HighGainPost vs Low is horizontal (that means that AMU cell is fully discharged), above this value dependence look like slanting line. If hg_max<1100 this channel is considered to have problem. After that it finds maximum low gain value given high gain value is less than hg_max but larger than hg_max-100. Found value is multiplied by 0.9 (lg_max) If no point was found in stated high gain region lg_max is set to 150. For finding high-low ratio points in the region (500<hg<hg_max, 40<lg<lg_max) are used. High-low ratio is extracted by fitting selected points with HighGain = a + b*LowGain using two approaches. First, it finds the line best fitting these points. Second, it fits distribution of HighGain/LowGain with gaus function.
For modules having some problems or bad slope ASIC or whole PbGl average is used.
Error codes are:
0x1 Failure to find HG upper limit
0x2 Failure to find LG upper limit
0x4 Number of points in found region is too small
0x8 Found high-low ratio is out of reasonable range
0x10 Chi2 obtained in fitting prosedure is large
/home/phnxpbgl/work/RawData/calib/HLRatio
  1. Make sure that HV is on.
  2. Force anyone using DAQ to leave it for 15 minutes
  3. Load Calibration trigger configuration
  4. Plug PPG cable to VY socket
  5. Turn on Tenma. 
    > ssh va009 -l phnxpbgl
> cd ~/Tenma
> ./setv.pl 25
  6. Make sure that PPG signal reach LEDs.
  7. Start run (one have to use partition including GL1)
  8. Go back to terminal with Tenma control and issue 
    > ./scanv.pl 25
  9. Make sure that Tenma is scaning voltage
  10. For best result issue twice 
    > ./scanv.pl 12
  11. Make corrections in hilo.dat
  12. Start root -l GetHiLo.C. It takes about one hour to fully process one file.
  13. At the output one will have a file named ak_hilo.txt and a bunch of plots of modules failed automated procedure. Check these plots and make neccessary corrections to ak_hilo.txt - put correct high-low values and replace corresponding errors with 0. Errors corresponding to bad yellow LEDs are corrected automaticaly at the next stage.
  14. Start root -l writeTracerHiloRatios.cmd. You'll have a complete set of high-low ratio values in ASCII format. It can be submitted to the DB
  15. IMPORTANT! Do not forget to plug PPG cable back!
Last update:
Andrey Kazantsev