Possibility to use time zero signal in drift speed fit for SDD injectors (F. Prino)

diff --git a/ITS/AliITSOnlineSDDInjectors.cxx b/ITS/AliITSOnlineSDDInjectors.cxx
index 748b3716a64489ecfd5a34b963f76765076d5414..33dd3b88ce8f8e85b6823cfc47096ef64d25a268 100644 (file)
--- a/ITS/AliITSOnlineSDDInjectors.cxx
+++ b/ITS/AliITSOnlineSDDInjectors.cxx
@@ -40,7 +40,7 @@ const UShort_t AliITSOnlineSDDInjectors::fgkDefaultTbMin[kInjLines] = {10,50,100
 const UShort_t AliITSOnlineSDDInjectors::fgkDefaultTbMax[kInjLines] = {20,70,120};
 
 //______________________________________________________________________
-AliITSOnlineSDDInjectors::AliITSOnlineSDDInjectors():AliITSOnlineSDD(),fHisto(),fTbZero(0.),fParam(),fPolOrder(0),fMinDriftSpeed(0.),fMaxDriftSpeed(0.),fMaxDriftSpeedErr(0.),fLowThreshold(0.),fHighThreshold(0.),fFirstPadForFit(0),fLastPadForFit(0),fPadStatusCutForFit(0),fTimeStep(0.)
+AliITSOnlineSDDInjectors::AliITSOnlineSDDInjectors():AliITSOnlineSDD(),fHisto(),fTbZero(0.),fRMSTbZero(0.),fParam(),fPolOrder(0),fMinDriftSpeed(0.),fMaxDriftSpeed(0.),fMaxDriftSpeedErr(0.),fLowThreshold(0.),fHighThreshold(0.),fFirstPadForFit(0),fLastPadForFit(0),fPadStatusCutForFit(0),fTimeStep(0.),fUseTimeZeroSignal(kFALSE)
 {
   // default constructor
   SetPositions();
@@ -48,7 +48,7 @@ AliITSOnlineSDDInjectors::AliITSOnlineSDDInjectors():AliITSOnlineSDD(),fHisto(),
   SetTimeStep(fgkDefaultTimeStep);
 }
 //______________________________________________________________________
-AliITSOnlineSDDInjectors::AliITSOnlineSDDInjectors(Int_t nddl, Int_t ncarlos, Int_t sid):AliITSOnlineSDD(nddl,ncarlos,sid),fHisto(),fTbZero(0.),fParam(),fPolOrder(0),fMinDriftSpeed(0.),fMaxDriftSpeed(0.),fMaxDriftSpeedErr(0.),fLowThreshold(0.),fHighThreshold(0.),fFirstPadForFit(0),fLastPadForFit(0),fPadStatusCutForFit(0),fTimeStep(0.)
+AliITSOnlineSDDInjectors::AliITSOnlineSDDInjectors(Int_t nddl, Int_t ncarlos, Int_t sid):AliITSOnlineSDD(nddl,ncarlos,sid),fHisto(),fTbZero(0.),fRMSTbZero(0.),fParam(),fPolOrder(0),fMinDriftSpeed(0.),fMaxDriftSpeed(0.),fMaxDriftSpeedErr(0.),fLowThreshold(0.),fHighThreshold(0.),fFirstPadForFit(0),fLastPadForFit(0),fPadStatusCutForFit(0),fTimeStep(0.),fUseTimeZeroSignal(kFALSE)
 { 
 // standard constructor
   SetPositions();
@@ -161,18 +161,34 @@ TGraphErrors* AliITSOnlineSDDInjectors::GetSelectedDriftSpeedGraph(Int_t minAcce
 }
 //______________________________________________________________________
 void AliITSOnlineSDDInjectors::CalcTimeBinZero(){
-  //
-  Float_t tzero=0.,intCont=0.;
+  // Get time zero from trigger signal
+  Float_t tzero=0.,intCont=0.,rmsPeak=0.;
+  Bool_t isTbUsed[256];
+  Int_t nTbUsed=0;
+  for(Int_t i=0;i<256;i++) isTbUsed[i]=0;
   for(Int_t ian=0;ian<fgkNAnodes;ian++){
     for(Int_t itb=1;itb<fTbMin[0];itb++){
       Float_t cont=fHisto->GetBinContent(itb,ian+1);
+      Float_t contm1=fHisto->GetBinContent(itb+1,ian+1);
+      Float_t contp1=fHisto->GetBinContent(itb-1,ian+1);
       if(cont>fLowThreshold){
-       tzero+=cont*float(itb);
-       intCont+=cont;
+       if(contm1>fHighThreshold || cont>fHighThreshold || contp1>fHighThreshold){
+         tzero+=cont*float(itb);
+         rmsPeak+=cont*float(itb)*float(itb);
+         intCont+=cont;
+         if(!isTbUsed[itb]){
+           isTbUsed[itb]=1;
+           ++nTbUsed;
+         }
+       }
       }
     }
   }
-  if(intCont>0) fTbZero=tzero/intCont;
+  if(intCont>0){ 
+    fTbZero=tzero/intCont;
+    fRMSTbZero=TMath::Sqrt(rmsPeak/intCont-fTbZero*fTbZero);
+  }
+  if(nTbUsed==1) fRMSTbZero=0.5; 
 }
 //______________________________________________________________________
 void AliITSOnlineSDDInjectors::FitDriftSpeedVsAnode(){
@@ -288,26 +304,32 @@ void AliITSOnlineSDDInjectors::CalcDriftSpeed(Int_t jpad){
       sumXY+=fPosition[i]*y[i]/ey[i]/ey[i];
       sumWEI+=1./ey[i]/ey[i];
       tzero=fTbZero/ey[i]/ey[i];
-      erry=ey[i];
+      erry=ey[i]/ey[i]/ey[i];
       npt++;
     }
   }
-  Float_t vel=0,evel=0;
+  Float_t slope=0.,eslope=0.;
+  if(npt==1){
+    slope=(sumY-tzero)/sumX;
+    eslope=erry/sumX;
+  }
   if(npt>1){ 
-    Float_t slope=(sumWEI*sumXY-sumY*sumX)/(sumWEI*sumXX-sumX*sumX);
-    Float_t eslope=TMath::Sqrt(sumWEI/(sumWEI*sumXX-sumX*sumX));
-    if(slope!=0 && fTimeStep>0.){
-      vel=1./slope*10000./fTimeStep;// micron/ns
-      evel=eslope/slope/slope*10000./fTimeStep;// micron/ns
+    if(fUseTimeZeroSignal){
+      sumY+=fTbZero/fRMSTbZero/fRMSTbZero;
+      sumX+=0.;
+      sumXX+=0.;
+      sumYY+=fTbZero*fTbZero/fRMSTbZero/fRMSTbZero;
+      sumXY+=0.;
+      sumWEI+=1./fRMSTbZero/fRMSTbZero;
     }
+    slope=(sumWEI*sumXY-sumY*sumX)/(sumWEI*sumXX-sumX*sumX);
+    eslope=TMath::Sqrt(sumWEI/(sumWEI*sumXX-sumX*sumX));
   }
-  if(npt==1){
-    Float_t slope=(sumY-tzero)/sumX;
-    Float_t eslope=erry/sumX;
-    if(slope!=0 && fTimeStep>0.){
-      vel=1./slope*10000./fTimeStep;// micron/ns    
-      evel=eslope/slope/slope*10000./fTimeStep;// micron/ns
-    }
+
+  Float_t vel=0,evel=0;
+  if(slope!=0. && fTimeStep>0.){
+    vel=1./slope*10000./fTimeStep;// micron/ns
+    evel=eslope/slope/slope*10000./fTimeStep;// micron/ns
   }
   if(vel>fMaxDriftSpeed||vel<fMinDriftSpeed || evel>fMaxDriftSpeedErr){ 
     vel=0.;
@@ -403,7 +425,7 @@ void AliITSOnlineSDDInjectors::FindCentroids(){
        if(cont<fLowThreshold) break;
        if(cont<fgkSaturation){
          fCentroid[jpad][jlin]+=cont*(Float_t)jjj;
-         fRMSCentroid[jpad][jlin]+=cont*TMath::Power((Float_t)jjj,2);
+         fRMSCentroid[jpad][jlin]+=cont*(Float_t)jjj*(Float_t)jjj;
          intCont+=cont;
        }
        jjj--;
@@ -414,7 +436,7 @@ void AliITSOnlineSDDInjectors::FindCentroids(){
        if(cont<fLowThreshold) break;
        if(cont<fgkSaturation){
          fCentroid[jpad][jlin]+=cont*float(jjj);
-         fRMSCentroid[jpad][jlin]+=cont*TMath::Power((Float_t)jjj,2);
+         fRMSCentroid[jpad][jlin]+=cont*(Float_t)jjj*(Float_t)jjj;
          intCont+=cont;
        }
        jjj++;

diff --git a/ITS/AliITSOnlineSDDInjectors.h b/ITS/AliITSOnlineSDDInjectors.h
index 7feb4414f65d1bf278a750dc4927b321a21800a2..2e3a6934672a11f964bb6d53dbfc2b6b2cbf58ce 100644 (file)
--- a/ITS/AliITSOnlineSDDInjectors.h
+++ b/ITS/AliITSOnlineSDDInjectors.h
@@ -48,7 +48,9 @@ class AliITSOnlineSDDInjectors : public AliITSOnlineSDD {
   void SetTimeStep(Float_t tstep) {
     fTimeStep=tstep;
   }
-
+  void SetUseTimeZeroSignal(Bool_t useTZ=kTRUE){
+    fUseTimeZeroSignal=useTZ;
+  }
   TGraphErrors* GetTimeVsDistGraph(Int_t jpad) const;
   TGraphErrors* GetDriftSpeedGraph() const;
   TGraphErrors* GetSelectedDriftSpeedGraph(Int_t minAcceptStatus) const;
@@ -108,6 +110,7 @@ class AliITSOnlineSDDInjectors : public AliITSOnlineSDD {
 
   TH2F* fHisto;                              // histogram of channel counts
   Float_t fTbZero;                           // Time zero for injector event
+  Float_t fRMSTbZero;                        // Error on time zero 
   Float_t fPosition[kInjLines];              // Coordinates of injector lines
   UShort_t fTbMin[kInjLines];                // Minimum time bin for each line
   UShort_t fTbMax[kInjLines];                // Maximum time bin for each line
@@ -130,7 +133,9 @@ class AliITSOnlineSDDInjectors : public AliITSOnlineSDD {
   Int_t fPadStatusCutForFit;         // minimum value of pad status for fit
 
   Float_t fTimeStep;                 // time bin value (25 or 50 ns)
+  Bool_t fUseTimeZeroSignal;         // flag for usage of time zero signal
+                                     // in drift speed calculation
 
-  ClassDef(AliITSOnlineSDDInjectors,4)
+  ClassDef(AliITSOnlineSDDInjectors,5)
 };
 #endif