run : st_sst_15136011_raw_1000014.daq
# of events : 1000

Online ped. & zero subtraction :

sideP :
  uped = (UInt_t)(ped + NSIGMA*rms + 0.5);
  uped = (uped - OFFSET + CONSTANT )&MASK;

side N:
  uped = (UInt_t)(ped - NSIGMA*rms + 0.5);
  uped = (uped - OFFSET - CONSTANT )&MASK;

with :
UInt_t  MASK      = 1023;
UInt_t  THRESHOLD = 700;
UInt_t  OFFSET    = 375;
UInt_t  NSIGMA    = 4;
UInt_t  CONSTANT  = 3;

Fig1 : number of strips for the cumulated P-ladders and N-ladders vs. event #

We see that :

1. the numbers of strips/event is constant vs. event #
2. there are some hot ladders on both side
3. the numbers of strips on P-side > number of strips on N-side : this may be due to the the fact that strips on N-side have a higher noise so the threshold NSIGMA*rms (where NSIGMA = 4) kills a lot of strips

Fig 2 : number of strips for the cumulated P-ladders and N-ladders vs. event # (break-down per ladder)
 
comments : 

1. for both P and N-ladders, only few ladders have a really high number of strips per event
2. removing these ladders gives <# strips P-side> ~ 500 , <# strips N-side> ~ 100

Fig 3 : number of strips for the cumulated P-ladders and N-ladders (break-down per ladder)
 
II) look at the offline reco

• plots for strips, clusters and points reconstructed with the offline code : here
• zip file with 20 pdf files for the charge matching plots : here