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Adjusted Tower Fitting

Updated on Mon, 2010-08-02 11:34. Originally created by znault on 2010-08-02 11:34.

Over the past week we have been working on the tower fits and correcting for the abundance of poor fit towers. Two things have been done to change this; Included code that will include the pre/post showers in the mip cuts and shifted the fitting region. The code that was added was in EEsmdCal.cxx and is below:


#if 1 //.... after pre/post calibration is avaliable
float preMipRelEneLow=0.6, preMipRelEneHigh=3.0; // tmp
float ene2Mip=tileEne[iT][iEtaX][iPhiX]/presMipE[iEtaX];
thr= thr && ene2Mip>preMipRelEneLow && ene2Mip<preMipRelEneHigh;
#endif

The shift of the fitting region was done in fitTower.C. The fit region was shifted over so it would no longer fit the pedestal as the mip peak. The region was also extended to include more of the tail. The function that was edited was posted below:

float fitGausLand(TH1F *h) {
char *funcd="myfunc";
/*This will search for a peak after the pedestal*/
h->GetXaxis()->SetRange(22,200);
int maxbind=h->GetMaximumBin();
float sig=h->GetRMS();
float sum=h->Integral();
float xcentd=h->GetBinCenter(maxbind);
float eta=atoi(h->GetName()+5);
//printf("eta=%f sum=%f\n",eta,sum);
TF1 *f1=(TF1 *)gROOT->GetFunction(funcd);
f1->SetParameters(xcentd,0,0,sig,sig);
float x1=xcentd-10;
// float x2=xcentd*2.;
float x2 = xcentd + 20.0;
if(x1<1) x1=1;
if(x2<xcentd) x2=xcentd+10;

h->Fit(funcd,"R","",x1,x2);
//h->Fit(funcd,"R","",20,70);
}

These changes did fix the majority of the poorly fit towers and did not greatly effect the already good towers. To show this we compare the first fit of the towers with the second fit that includes the pre/post and the shift of 02TE01-12.

First Pass:
Tower # Counts MIP MIP σ Gains Gain σ Χ^2 Deg. Freedom Reduced X^2
02TB01 1196 6.15 0.102 17.02 0.88 26.78 6 4.46
02TB02 1334 6.95 0.089 19.31 0.86 38.95 9 4.33
02TB03 1309 7.50 0.073 20.38 0.84 39.83 10 3.98
02TB04 1227 8.65 0.081 23.23 0.84 37.61 12 3.13
02TB05 1233 10.41 0.100 27.79 0.84 51.32 16 3.21
02TB06 1210 9.62 0.091 25.37 0.82 75.10 13 5.78
02TB07 1239 10.77 0.110 27.94 0.82 41.81 13 3.22
02TB08 974 12.24 0.110 31.08 0.81 25.42 15 1.69
02TB09 1021 12.71 0.120 31.62 0.8 26.07 16 1.63
02TB10 1025 14.40 0.100 35.32 0.81 46.08 20 2.3
02TB11 931 15.22 0.100 36.57 0.76 64.39 22 2.93
02TB12 784 16.23 0.170 35.06 0.76 23.75 22 1.08



Second Pass [pre/post + shift] :
Tower # Counts MIP MIP σ Gains Gain σ Χ^2 Deg. Freedom Reduced X^2
02TB01 1100 6.11 0.074 16.93 0.86 53.87 21 2.57
02TB02 1297 6.88 0.078 19.12 0.85 51.80 20 2.59
02TB03 1313 7.50 0.074 20.38 0.84 58.32 22 2.65
02TB04 1223 8.58 0.080 23.02 0.84 25.08 24 1.05
02TB05 1221 10.42 0.100 27.82 0.84 57.78 25 2.31
02TB06 1159 9.54 0.090 25.18 0.82 49.81 24 2.08
02TB07 1242 10.82 0.110 28.08 0.82 67.14 24 2.8
02TB08 972 12.30 0.100 31.25 0.82 38.07 25 1.52
02TB09 998 12.47 0.120 31.67 0.8 28.47 25 1.14
02TB10 1007 14.40 0.100 35.33 0.8 44.87 26 1.73
02TB11 939 15.03 0.140 36.11 0.79 47.60 27 1.76
02TB12 757 16.23 0.160 37.89 0.8 30.25 25 1.21
 
 
 
The MIP value between the two are very close and shows that the change does not alter the MIP ADC greatly. The Reduced X2 on the other hand does change and shows that the new fit does a much better job. One main reason for this is the addition of the tail being fit. This, of course, includes more events that are fit.


 

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