Minutes of the HEC/FCAL Testbeam Analysis Meeting from 23.2.00.
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1. HEC_ADC Status and Planning
   (C. Sbarra)
   
   
   Carla presented the status of the hec_adc version 3.8. Changes are due to
   the incorporation of the latest calibration files, new functionalities in 
   the dig package, the slow control histogramming and the handling of the HV
   status. A preliminary version 3.9 is used for the technical run (only one
   module present).
   
   
2. HEC_ADC: conversion to OO
   (R. Sobie)

  
   Randy is exploring the possibility of an OO HEC testbeam software prototype.
   He presented the ideas how to get started.

    
3. HEC: X-Talk of Electron and Muon Signals: Testbeam 99 Results
    (L. Kurchaninov/M. Levitsky)
  
  
   Leonid presented the x-talk calculations for the calibration signal and real
   event signal. They are rather close, typically at the level of 1.1% for a
   resistivity of 1 Mohm/square. Looking at the electron data, the value 
   obtained is typically 2.0%-2.5%. Due to the leakage of the electron signal
   into the neighbouring pad, this value has to be considered as an upper-limit
   for the x-talk. For muons this leakage is absent, but the signal itself is
   rather small. The x-talk seen is at the level of a few nA. This yields 
   typical values of 2.5% for the x-talk, but the error is presumably large
   (presumably larger than 50% ?). In the present technical run more precise
   x-talk measurements will be derived from the calibration signal. 
  
  
   
4. HEC: Electron and Pion Results: Testbeam 99
   (D. Fortin)
    
    
    Dominique presented an update of the testbeam results from the august 99 
    run. Detailed noise studies show, that the noise for some channels 
    (bad channels) shows quite some variation with time. For some channels the
    noise can get quite large and shows a non-gaussian behaviour (Following 
    the run the FEB boards were re-tested in the lab and indeed quite a few 
    channels have been repaired (pre-shaper, shaper,line-driver)).
    
    The energy resolution for electrons yields a sampling term
    of about 24% in comparison to 22% in 98 (the constant term being compatible
    with 0). This might result partially from the data taken close to the 
    tie-rods. Also the lower precision of calibration constants affects the
    energy resolution. The linearity of the energy response shows an offset
    of typically 300 MeV, which might be related to these calibration problems.
    
    Also for pions a deterioration of the energy resolution with respect to 
    the 98 data is seen: the sampling term is typically 82% in comparison to 
    75%. The constant term is - as measured from the 98 data - at the level
    of 6%. The results are rather consistent with the analysis presented by 
    Andrej in the previous meeting.
    
   
5. HEC: Electron Results: Testbeam 99
   (N. Javadov)
   
   
   Namig presented his electron results from the august 99 run. Data from the
   impact points L and M have been analyzed. The energy resolution has been 
   studied varying the cluster size used for the reconstruction.

   
6. HEC: Pion Results: Testbeam 99
   (I. Pisarev)
   
   
   Igor presented his pion results from the august 99 run. The pion data from
   the impact point M have been used. The cluster size has been varied: 18,
   26 and 36 channels. The noise has been obtained from the fit (3 parameter) 
   to the energy resolution (i.e. a constant noise contribution at the various
   energies has been assumed). For the 26-cell cluster size a sampling term of
   typically 95% has been obtained, the constat term is typically 6%.
   

7. HEC: MC and Experiment: Comparison for Muons and Electrons
   (A. Kiryunin)
   
   
   Andrej presented a comparison of the MC data with the electron and muon 
   results from Michael and Andrej. In particular he considered the scale 
   factor from the visual deposited energy given by the MC (GeV) to the
   measured signal in nA. For electrons this scale factor is about 
   8750 nA/GeV. For the muons the data have been corrected for the x-talk. 
   The effect of the noise contribution to the scale factor has been studied
   in detail. Averaging over the muons of 120 GeV and 200 GeV a scale factor
   of 8680 nA/GeV is obtained. The variation of the muon signal over
   three orders of magnitude is well described by the MC. The difference
   between the two energies is at the level of 2%. The good agreemnet between 
   the electron and muon scale factors indicates a good agreement of the 
   electron/muon ratio with MC expectations.    
   
   
8. FCAL: Electron Position Resolution and Position Correction to the Energy
   Determination.
   (J. Rutherfoord)
  
  
   John presented the analysis from A. Savin of the FCAL data taken in 98. The
   high statistic sample of electron data allowed to study the correlation 
   between the total energy deposited and the impact position of the beam 
   particle. The impact position can be obtained either from the MWPC 
   information or the assymetries as measured from the individual channels.
   Up to 12 assymetries per event have been used in total. It has been shown,
   that the impact position can be obtained with a precision of less than 1 mm 
   using the assymetry information. The energy deposition is correlated with 
   the impact position due to the fine substructure of the FCAL
   calorimeter. Using this correction, the relative improvement of the electron
   energy resolution is at the level of 30%.