From 0e1b7412e1c1ec939857ec2acf34319289f5c785 Mon Sep 17 00:00:00 2001
From: zampolli <chiara.zampolli@cern.ch>
Date: Mon, 1 Sep 2014 15:13:53 +0200
Subject: [PATCH] Fix on vertex uncertainties evaluation in case SPD vertex
 used for MeanVertex calibration (D. Caffarri)

---
 .../ITS/AliMeanVertexPreprocessorOffline.cxx  | 56 ++++++++++---------
 1 file changed, 29 insertions(+), 27 deletions(-)

diff --git a/PWGPP/ITS/AliMeanVertexPreprocessorOffline.cxx b/PWGPP/ITS/AliMeanVertexPreprocessorOffline.cxx
index 285a097db37..e3bf8ec5814 100644
--- a/PWGPP/ITS/AliMeanVertexPreprocessorOffline.cxx
+++ b/PWGPP/ITS/AliMeanVertexPreprocessorOffline.cxx
@@ -211,10 +211,10 @@ void AliMeanVertexPreprocessorOffline::ProcessOutput(const char *filename, AliCD
       if ((useTRKvtx==kFALSE) && (useITSSAvtx==kFALSE)){
 	AliError(Form("Also SPD vertex histograms have too few entries for fitting, return"));
 	fStatus=kLowStatistics;
-			return;		 
+	return;		 
       }
     }
-	
+    
     if((nEntriesX == 0.)&&(nEntriesY==0.) && (nEntriesZ>0.)){
       vertexerSPD3Doff = kTRUE;
       AliWarning("Vertexer SPD 3D off");
@@ -305,6 +305,7 @@ void AliMeanVertexPreprocessorOffline::ProcessOutput(const char *filename, AliCD
       histSPDvtxX ->Fit("gaus", "M");
       fitVtxX = histSPDvtxX -> GetFunction("gaus");
       xMeanVtx = fitVtxX -> GetParameter(1);
+      xSigmaVtx = fitVtxX -> GetParameter(2);
       if (TMath::Abs(xMeanVtx) > 2.) {
 	xMeanVtx = 0.;
 	writeMeanVertexSPD=kTRUE;
@@ -313,6 +314,7 @@ void AliMeanVertexPreprocessorOffline::ProcessOutput(const char *filename, AliCD
       histSPDvtxY ->Fit("gaus", "M");
       fitVtxY = histSPDvtxY -> GetFunction("gaus");
       yMeanVtx = fitVtxY -> GetParameter(1);
+      ySigmaVtx = fitVtxY -> GetParameter(2);
       if (TMath::Abs(yMeanVtx) > 2.) {
 	yMeanVtx = 0.;
 	writeMeanVertexSPD=kTRUE;
@@ -611,28 +613,28 @@ void AliMeanVertexPreprocessorOffline::ProcessOutput(const char *filename, AliCD
     
      if (highMultEnvironment==kTRUE || highMultppEnvironment==kTRUE){
     
-    projXvsMult -> Fit("gaus", "M", "", -0.4, 0.4);
-    sigmaFitX = projXvsMult -> GetFunction("gaus");
-    xSigmaMult = sigmaFitX->GetParameter(2);
-	  
-      if ((xSigmaMult <0) || (xSigmaMult>0.03)){
-	AliWarning(Form("Problems with luminosiy region determination, update of the postion only"));
-	xSigmaMult = 0.;
-	xSigmaVtx = 0.0120;
-	fStatus=kLumiRegCovMatrixProblem;
+       projXvsMult -> Fit("gaus", "M", "", -0.4, 0.4);
+       sigmaFitX = projXvsMult -> GetFunction("gaus");
+       xSigmaMult = sigmaFitX->GetParameter(2);
+       
+       if ((xSigmaMult <0) || (xSigmaMult>0.03)){
+	 AliWarning(Form("Problems with luminosiy region determination, update of the postion only"));
+	 xSigmaMult = 0.;
+	 xSigmaVtx = 0.0120;
+	 fStatus=kLumiRegCovMatrixProblem;
+       }
+       else{
+	 xSigmaVtx = xSigmaMult;
+	 xSigmaVtx = xSigmaVtx*1.1;
       }
-      else{
-	xSigmaVtx = xSigmaMult;
-	xSigmaVtx = xSigmaVtx*1.1;
-      }
-	  
-      projYvsMult -> Fit("gaus", "M", "", -0.2, 0.5);
-      TCanvas *c = new TCanvas("nwC", "nwC");
-      c->cd();
-      projYvsMult->Draw();
+       
+       projYvsMult -> Fit("gaus", "M", "", -0.2, 0.5);
+       TCanvas *c = new TCanvas("nwC", "nwC");
+       c->cd();
+       projYvsMult->Draw();
       sigmaFitY = projYvsMult -> GetFunction("gaus");
       ySigmaMult = sigmaFitY->GetParameter(2);
-	  
+      
       if ((ySigmaMult <0) || (ySigmaMult>0.03)){
 	AliWarning(Form("Problems with luminosiy region determination, update of the postion only"));
 	ySigmaMult = 0.;
@@ -643,12 +645,12 @@ void AliMeanVertexPreprocessorOffline::ProcessOutput(const char *filename, AliCD
 	ySigmaVtx = ySigmaMult;
 	ySigmaVtx = ySigmaVtx*1.1;
       }
-    	  
+      
       TProfile *htrkXZ = histTRKVertexXZ ->ProfileY();
       htrkXZ -> Fit("pol1", "M", "", -10., 10.);
       corrFit = htrkXZ->GetFunction("pol1");
       corrXZ = corrFit->GetParameter(1);
-	  
+      
       if (TMath::Abs(corrXZ) > 0.01) {
 	AliWarning(Form("Problems in the correlation fitting, not update the covariance matrix"));
 	corrXZ =0.;
@@ -658,12 +660,12 @@ void AliMeanVertexPreprocessorOffline::ProcessOutput(const char *filename, AliCD
 	covarXZ = corrXZ * zSigmaVtx*zSigmaVtx;
 	    
       }
-	  
+      
       TProfile *htrkYZ = histTRKVertexYZ ->ProfileY();
       htrkYZ -> Fit("pol1", "M", "", -10., 10.);
       corrFit = htrkYZ->GetFunction("pol1");
       corrYZ = corrFit->GetParameter(1);
-	  
+      
       if (TMath::Abs(corrYZ) > 0.01) {
 	AliWarning(Form("Problems in the correlation fitting, not update the covariance matrix"));
 	corrYZ =0.;
@@ -672,9 +674,9 @@ void AliMeanVertexPreprocessorOffline::ProcessOutput(const char *filename, AliCD
       else{
 	covarYZ = corrYZ*zSigmaVtx*zSigmaVtx;
       }
-	  
+      
      }
-	
+     
      Double_t position[3], covMatrix[6];
      Double_t chi2=1.; 
      Int_t nContr=1;	
-- 
2.43.0