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13) ver 1.2 : SMD-E, -P, status & relative gains, no Crate4

Updated on Mon, 2008-07-28 12:33. Originally created by balewski on 2008-07-21 11:28. Under:

Automatic BSMD-E, -P   relative calibration and status tables. 

The second pass through both SMDE, SMDP was performed, learning from previous mistakes.

Main changes:

  • relax most of the QA cuts
  • smooth raw spectra to reduce significance 1-2 channels wide  of spikes and deeps in raw spectra
  • extend slop fit range to ped +[30,100]
  • still do not use crate 4 - it has to many problems
  • reduce margin for gain correction - now 10%+ deviation is corrected.  

INPUT: 3M d-AU events from day ~336 of 2007.

All spectra were pedestals subtracted, using one value per strip, CAPS=123,124,125 were excluded. Below I'll use term 'ped' instead of more accurate pedestal residuum.

Method: fit slopes to ADC =ped+30,ped+100 or 5*sig(ped) if too low.

The spectra,  fits of pedestal residuum, and slopes were QAed.

Note, BSMD rate 4 had old resistors in day 366 of 2007 and was excluded from this analysis.
This reduces # of strips from 18,000 to 15,750 . 

 

Table 1 Definition of QA cuts, all plots (PDF1) 
cut# cut code description # of discarded E strips # of discarded P strips figure in PDF1
1 1 at least 10,000 entries in the MPV bin 4 ? -
2 2  sig(ped) of gauss fit <~13 ADC ch 13 11 Fig 1
3 4  position of mean gauss within +/- 4 ADC  10 8 Fig 2
4 8  yield from [ped+30,ped+100] out of range 513 766 Fig 3
5 16  chi2/dof<2.3 from slop fit  6 1 Fig 4
6 32  slopeError/slop >10% 5 0 Fig 5
7 64  slope in range 19 6 Fig 6
-  sum  out of processed 15,750 strips discarded  635 ==> 4.0%  789 ==> 5.0%  

 

 

Relative gain corrections for every eta bin 

Method : find average slope per eta slice, fit gauss, determine average slope : avrSlope(iEta)

Gain correction formula is used only for extreme deviations:  

  • gainCorr_i = slope_i/avrSlope(iEta),  i =1,..,18,000
  • if( fabs(1-gainCorr)<0.10) gainCor=1.0  // do not correct

PDF2 plots  shows: 

  • Fig 1  SMDE status table, distribution per module
  • Fig 2  SMDP status table, distribution per module
  • Fig 3  SMDE  gain corrections,  changed 3408 strips=22%
  • Fig 4  SMDP  gain corrections,  changed 2067 strips=13%

Summary of BSMDE,P status tales and gains , ver 1.2 

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