//

[u/mrichter/AliRoot.git] / TPC / Upgrade / macros / fitResolution.C

diff --git a/TPC/Upgrade/macros/fitResolution.C b/TPC/Upgrade/macros/fitResolution.C
new file mode 100644 (file)
index 0000000..2f48c90
--- /dev/null
+++ b/TPC/Upgrade/macros/fitResolution.C
@@ -0,0 +1,59 @@
+void EmpiricalGEMQFit(){
+  //
+  // Empirical fit of the relative Q resolution for the iron source with 4 GEM layers
+  // Fit:
+  // Assumption : 
+  // 1.) Effective electron transparency proportiaonal to the effective ion transparency
+  // 2.) RMS of the effecitive gain can be expressed as linear function of U1/U3,U2/U4 and U3/U4
+  //
+  // Agreement with data within the expect error estimate -relative agreement 
+  // RMS (sigma_{meas}/sigma_{fit}) ~ 3%
+  // 
+  TFile *fgem = TFile::Open("GEMScansIKF.root");
+  TTree * tree= (TTree*)f.Get("NeCO2N2");
+  tree->SetMarkerStyle(25);
+  TStatToolkit toolkit;
+  Double_t chi20=0;
+  Int_t    npoints=0;
+  Int_t npointsMax=10000;
+  TVectorD param0,param1,param2,param3;
+  TMatrixD covar0,covar1,covar2,covar3;
+  
+  tree->SetAlias("UGEMA","(UGEM1+UGEM2+UGEM3+UGEM4)");
+  TString fstringFast="";
+  fstringFast+="1/IB++";                // fraction of the 
+  fstringFast+="(UGEM1/UGEMA)/IB++";    // fraction of the gain
+  fstringFast+="(UGEM2/UGEMA)/IB++";    // fraction of the gain
+  fstringFast+="(UGEM3/UGEMA)/IB++";    // fraction of the gain
+  //
+  TString *strResolFit = TStatToolkit::FitPlane(tree,"Sigma^2:Sigma^2", fstringFast.Data(),cutFit, chi20,npoints,param0,covar0,-1,0, npointsMax, 0);
+  strResolFit->Tokenize("++")->Print();
+  tree->SetAlias("fitSigma2",strResolFit->Data());
+  //
+  gStyle->SetOptTitle(0);
+  //
+  TCanvas *canvas = new TCanvas("canvasEmp","canvasEmp",600,500);
+  canvas->SetBottomMargin(0.15);
+  canvas->SetRightMargin(0.1);
+  canvas->SetTicks(1,1);
+  tree->SetMarkerSize(0.7)
+  tree->Draw("Sigma:sqrt(fitSigma2):sqrt(1/IB)",cutFit,"colz");  
+  TH2F *htemp = (TH2F*)gPad->GetPrimitive("htemp");
+  htemp->GetXaxis()->SetTitle("#sigma_{fit}(%)");
+  htemp->GetYaxis()->SetTitle("#sigma_{meas}(%)");
+  htemp->GetZaxis()->SetTitle("#sqrt{IBF}");
+  htemp->SetTitle("Fe resolution");
+  htemp->GetXaxis()->SetLimits(8,20);
+  htemp->GetYaxis()->SetLimits(8,20);
+  htemp->Draw("colz");
+  TLatex latex;
+  latex.DrawLatex(8.5,18.5,"#sigma=#sqrt{p_{0}+p_{1}#frac{1}{IB}+p_{2}#frac{U1}{U4xIB}+p_{3}#frac{U2}{U4xIB} + p_{4}#frac{U3}{U4xIB}}");
+  latex.DrawLatex(8.5,17,TString::Format("p_{0}=%1.f",param0[0]));
+  latex.DrawLatex(8.5,16,TString::Format("p_{1}=%1.f",param0[1]));
+  latex.DrawLatex(8.5,15,TString::Format("p_{2}=%1.f",param0[2]));
+  latex.DrawLatex(8.5,14,TString::Format("p_{3}=%1.f",param0[3]));
+  latex.DrawLatex(8.5,13,TString::Format("p_{4}=%1.f",param0[4]));
+
+  canvasFit->SaveAs("canvasFEResolutionFit.pdf");
+  canvasFit->SaveAs("canvasFEResolutionFit.png");
+}