Sector 5-8 tower gains from MIP analysis using UxV method. ( 5-Iteration, final for 2004)

  • events from the selected runs with TPC in the data were added together, runList
  • any minB triggered events are used (fast & slow), total 1.5M accepted eve
  • few intermediate ped tables loaded to DB.
  • Goal-1: determine absolute tower gains
  • Goal-2: determin eta dependent factor converting slopes to absolute gains

    240 Tower spectra are this directory.
    * 'a'- plots are raw inclusive spectra for all events, used to get ped residual, fitted with a Gaussian.
    * 'd'- plots are best MIP selection. Required : UxV in SMD and ADC-ped>thres in pres1, pres2, and post. If a pre or post shower is dead it was ignored. Fitted with a mix of Gaussian & Landau with common X0.
    Examples of MIP spectra for towers at various eta bins (ignore vertical lines, the 4-th plot is not typical):

    Mean X0's from both fits are used below.
    * Formula: gain(ch/GeV) = gain=2.89*TanH(eta)*(MIP-Ped)
    err^2= errMip^2 + errPed^2 + 0.3^2, last 0.3 accounts for peds systematic error

  • 6 out of 240 towers have no gains:
    - ped only: 05TE03 , 05TD10, 07TB09
    - broken FEE: 06TA03
    - negative ped: 08TD04
    - hot 06TD11
    FINAL GAINS FOR 2004 DATA
  • DB format {name, gain, error} gains05tower.dat , gains06tower.dat , gains07tower.dat , gains08tower.dat .
  • Suggested HV change for 2005 run.
    For towers with gain deviation above +/- 10% from the goal gains it is worth change HV. The detailed list of towers with desire gain change factor . Table below summaries # of towers in sectors 5-8 with low/high/ok HV vs. eta bin.
    eta bin high HV low HV OK HV dead in pp200
    1 0 15 5 -
    2 2 8 10 -
    3 4 4 10 2
    4 1 8 10 1
    5 1 12 7 -
    6 1 10 9 -
    7 4 7 9 -
    8 2 10 8 -
    9 1 13 5 1
    10 4 4 11 1
    11 5 6 8 1
    12 1 5 14 -
    sum 26 102 106 6
    1. Scale for gains from pp200 slopes. For each eta bin the mean value of the product 'gain(MIP UxV)*slope' was determined. There is 20 towers per eta bin in most cases. The plots with ratios _after_ scale correction are here. X-axis [0.5,1.5] , ( PS ).

      eta bin mean
      gain(MIP UxV)*slope
      (1/GeV)       		sigma of
      distribution
      (1/GeV)
      1 -2.26 0.22
      2 -2.64 0.23
      3 -2.88 0.38
      4 -2.92 0.32
      5 -3.00 0.38
      6 -3.36 0.52
      7 -3.60 0.29
      8 -3.64 0.30
      9 -3.98 0.38
      10 -4.30 0.40
      11 -4.44 0.33
      12 -4.41 0.24

    2. Comparison of Y=gains(MIP UxV) vs. X=gain(slopes). One plot for each eta bin. Green diagonal line is Y=X. Blue horizontal line shows ideal gain, dashed +/- 10 %. The range of both axis is the same, fixed to [0,50] ch/GeV. ( PS ).
    3. The same comparison of Y=gains(MIP UxV) vs. X=gain(slopes), but with auto-scaling X & Y axis. ( PS ).

      Conclusions:
      * slopes should work fine for sectors 9-4

      Code used by Murad fitTwA.C and original output towerGains.dat
      Jan's code to display all this plots twGmult.C