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toward BTOW HV mapping

Updated on Tue, 2009-03-03 23:14. Originally created by balewski on 2009-03-03 21:58.

 The following runs were taken on March 3rd, runs 10062047-61

 Table 1.

HV set run# tot eve run time BBC_coin prescale
id%7=0 61 100K 5min 250
id%7=1 47 32K 3min 1000
id%7=2 48 52K 4min 1000
id%7=3 49 50K 4min 1000
id%7=4 50 50K 5min 1000
id%7=5 51 49K 7min 1000
id%7=6 60 100K 5min 250

 Identified problems:

  • BBC prescale was set too high and DAq event rate was 200-400 Hz
  • TCD phase was 24 ns off optimal value 

Example of  raw spectra for set0 are in attachment 1. Towers with HV=ON if softID=N*7 have few counts above ped.

Fig 0. Raw ADC spectra for 3 consecutive towers. Tower 7 has HV=ON.

 

Fig 1. run #61, towers with softID=N*7 have HV=ON.

A) sigma of pedestal, accepted [0.65,2.2], serves as rudimentary tower QA

B) integral over [ped+5*sig, 4096] for towers with HV=ON. If integral >=7 counts we call tower 'active'.

C) eta-phi distribution of active towers with HV=ON 

D) eta-phi distribution of active towers with HV=OFF   

Fig 2. run #47, towers with softID=N*7+1 have HV=ON.

 

 Conclusions:

  • With available stats we see clear patter for active towers with HV=ON 
  • but we were forced to set event threshold so low we can't be sure we excluded only towers with HV=OFF
  • ~10x more stats is needed: -- > increase event rate to ~2kHz

 

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