from ROOT import TTree, TFile, TCanvas, TH1F, TLorentzVector
%jsroot on
Welcome to JupyROOT 6.07/07
file = TFile("data/Dimuons.root","READ");
Let's calculate again the invariant mass $M$ of two muons and focus on various parts of the dimuon mass spectrum
Upsilon = TH1F("ϒ", "#mu#mu mass;#mu#mu mass [GeV];Events", 100, 8.0, 12.5)
for dimu in file.Dimuons:
if dimu.Muon1_Global and dimu.Muon2_Global:
muon1 = TLorentzVector(dimu.Muon1_Px, dimu.Muon1_Py, dimu.Muon1_Pz, dimu.Muon1_Energy)
muon2 = TLorentzVector(dimu.Muon2_Px, dimu.Muon2_Py, dimu.Muon2_Pz, dimu.Muon2_Energy)
Invariant_Mass = (muon1+muon2).M()
if Invariant_Mass > 0.0 and Invariant_Mass < 120.0:
Upsilon.Fill(Invariant_Mass)
from ROOT import TF1, kGreen, kRed, kYellow, kOrange
Canvas = TCanvas()
Gaussian = TF1("Gaussian","gaus", 9.23, 9.6)
Background = TF1("Background","pol2", 8, 12.5)
Gaussian1 = TF1("Gaussian","gaus", 9.7, 10.2)
Gaussian2 = TF1("Gaussian","gaus",10.25, 10.45)
Gaussian.SetLineColor(kRed)
Background.SetLineColor(kGreen)
Gaussian1.SetLineColor(kYellow)
Gaussian2.SetLineColor(kOrange)
Upsilon.Fit(Gaussian,"R")
Upsilon.Fit(Background,"R+")
Upsilon.Fit(Gaussian1,"R++")
Upsilon.Fit(Gaussian2,"R+++")
Canvas.Draw()
FCN=129.611 FROM MIGRAD STATUS=CONVERGED 79 CALLS 80 TOTAL EDM=3.72629e-07 STRATEGY= 1 ERROR MATRIX ACCURATE EXT PARAMETER STEP FIRST NO. NAME VALUE ERROR SIZE DERIVATIVE 1 Constant 2.23626e+03 2.67862e+01 1.05039e-01 3.01623e-05 2 Mean 9.44597e+00 1.47445e-03 7.95168e-06 -6.01384e-02 3 Sigma 1.29456e-01 1.92562e-03 2.21217e-05 2.14839e-01 **************************************** Minimizer is Linear Chi2 = 5823.89 NDf = 97 p0 = -11545.9 +/- 169.277 p1 = 2289.96 +/- 34.3334 p2 = -104.204 +/- 1.7093 FCN=92.7142 FROM MIGRAD STATUS=CONVERGED 101 CALLS 102 TOTAL EDM=7.87272e-08 STRATEGY= 1 ERROR MATRIX ACCURATE EXT PARAMETER STEP FIRST NO. NAME VALUE ERROR SIZE DERIVATIVE 1 Constant 1.26738e+03 1.67043e+01 5.54257e-02 -1.62258e-05 2 Mean 1.00214e+01 5.58077e-03 1.93186e-05 1.64938e-02 3 Sigma 2.48927e-01 8.95793e-03 4.57262e-05 6.26346e-03 FCN=0.83442 FROM MIGRAD STATUS=CONVERGED 131 CALLS 132 TOTAL EDM=3.96479e-10 STRATEGY= 1 ERROR MATRIX ACCURATE EXT PARAMETER STEP FIRST NO. NAME VALUE ERROR SIZE DERIVATIVE 1 Constant 1.18081e+03 2.76034e+01 1.15695e-02 -9.96052e-07 2 Mean 1.03421e+01 1.03389e-02 6.82040e-06 1.07995e-03 3 Sigma 1.85942e-01 4.67600e-02 8.20126e-05 -2.13027e-04