My ROOT Exercise with MC Ntuples

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My ROOT Exercise with MC Ntuples

Wen-Chen Chang2010/12/15

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Outline

• 姚錫弘 successfully converts the MySQL tables of MC run into a ROOT ntuple file with an event-loop structure: /sp8data11/shyao/rootfile/r321test.root .

• As an exercise of ROOT, I study the E906 acceptance of dimuon pairs in mass, xf, x1, x2, phi_mu and theta_mu.

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Ntuple Variables/sp8data11/shyao/rootfile/branchname.txt

*Tree :event : A tree with data taken from SQL, 2010/12/01 **Entries : 406055 : Total = 1835613408 bytes File Size = 1149489047 **Br 0 :runID : runID/I **Br 1 :seed : seed/I **Br 2 :nEvGen : nEvGen/I **Br 3 :extraWeight : extraWeight/D **Br 4 :beamMomentum : beamMomentum/D **Br 5 :beamCurrent : beamCurrent/D **Br 6 :asciiFieldMap : asciiFieldMap/O **Br 7 :energyCut : energyCut/D **Br 8 :recordMethod : recordMethod[10]/C **Br 9 :eventPos : eventPos[10]/C **Br 10 :dimuonSource : dimuonSource[10]/C **Br 11 :dimuonRepeat : dimuonRepeat/I **Br 12 :magneticField : magneticField/O **Br 13 :generator : generator[32]/C **Br 14 :trackingEnergyCut : trackingEnergyCut/D **Br 15 :trackingZCut : trackingZCut/D **Br 16 :numSpills : numSpills/I **Br 17 :numHits : numHits/I **Br 18 :numTracks : numTracks/I **Br 19 :numDimuons : numDimuons/I **Br 20 :timeStart : timeStart[32]/C **Br 21 :timeStop : timeStop[32]/C **Br 22 :geoVersion : geoVersion[128]/C **Br 23 :lastUpdate : lastUpdate[32]/C **Br 24 :spillID : spillID/I **Br 25 :target : target[32]/C **Br 26 :eventID : eventID/I *

*Br 27 :nDimuons : nDimuons/I **Br 28 :nTracks : nTracks/I **Br 29 :mProcessCode : mProcessCode[32]/C **Br 30 :mWeight : mWeight/D **Br 31 :mMandS : mMandS/D **Br 32 :mMandU : mMandU/D **Br 33 :mMandT : mMandT/D **Br 34 :mPT : mPT/D **Br 35 :mInvarMass : mInvarMass/D **Br 36 :mEventsGen : mEventsGen/I **Br 37 :dimuonID : dimuonID/I **Br 38 :trackID1 : trackID1/I **Br 39 :trackID2 : trackID2/I **Br 40 :mass : mass/D **Br 41 :xF : xF/D **Br 42 :x1 : x1/D **Br 43 :x2 : x2/D **Br 44 :pT : pT/D **Br 45 :dx : dx/D **Br 46 :dy : dy/D **Br 47 :dz : dz/D **Br 48 :dpx : dpx/D **Br 49 :dpy : dpy/D **Br 50 :dpz : dpz/D **Br 51 :energy : energy/D **Br 52 :phi_gam : phi_gam/D **Br 53 :phi_mu : phi_mu/D **Br 54 :theta_mu : theta_mu/D **Br 55 :sigWeight : sigWeight/D **Br 56 :acceptS123 : acceptS123/O **Br 57 :acceptAll : acceptAll/O *

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Ntuple Variables/sp8data11/shyao/rootfile/branchname.txt

*Br 58 :trackID : trackID[nTracks]/I **Br 59 :parentID : parentID[nTracks]/I **Br 60 :parentID2 : parentID2[nTracks]/I **Br 61 :particleID : particleID[nTracks]/I **Br 62 :parentParticleID : parentParticleID[nTracks]/I **Br 63 :parentParticleID2 : parentParticleID2[nTracks]/I **Br 64 :x0 : x0[nTracks]/D **Br 65 :y0 : y0[nTracks]/D **Br 66 :z0 : z0[nTracks]/D **Br 67 :xf : xf[nTracks]/D **Br 68 :yf : yf[nTracks]/D **Br 69 :zf : zf[nTracks]/D **Br 70 :px0 : px0[nTracks]/D **Br 71 :py0 : py0[nTracks]/D **Br 72 :pz0 : pz0[nTracks]/D **Br 73 :pxf : pxf[nTracks]/D **Br 74 :pyf : pyf[nTracks]/D **Br 75 :pzf : pzf[nTracks]/D **Br 76 :ke0 : ke0[nTracks]/D **Br 77 :thxSt1 : thxSt1[nTracks]/D **Br 78 :thySt1 : thySt1[nTracks]/D **Br 79 :thxSt2 : thxSt2[nTracks]/D **Br 80 :thySt2 : thySt2[nTracks]/D **Br 81 :charge : charge[nTracks]/S **Br 82 :hitSt1 : hitSt1[nTracks]/O **Br 83 :hitSt2 : hitSt2[nTracks]/O **Br 84 :hitSt3 : hitSt3[nTracks]/O **Br 85 :hitSt4 : hitSt4[nTracks]/O **Br 86 :protonID : protonID[nTracks]/I *

*Br 87 :nHits : nHits/I **Br 88 :hitID : hitID[nHits]/I

**Br 89 :hit_trackID : hit_trackID[nHits]/I

**Br 90 :deltaEnergy : deltaEnergy[nHits]/D

**Br 91 :hx : hx[nHits]/D

**Br 92 :hy : hy[nHits]/D

**Br 93 :hz : hz[nHits]/D **Br 94 :hpx : hpx[nHits]/D

**Br 95 :hpy : hpy[nHits]/D

**Br 96 :hpz : hpz[nHits]/D

**Br 97 :hit_particleID : hit_particleID[nHits]/I

*

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Acceptance= #of Event Accepted /# of Event Generated

• In principle, the variable “acceptAll” should be 1 if both mu+ and mu- are detected in ST1-ST4. But somehow it was always zero when I first looked into it. So I use “hitSt4[0]*hitSt3[0]*hitSt2[0]*hitSt1[0]*hitSt4[1]*hitSt3[1]*hitSt2[1]*hitSt1[1]>0” to represent the cut condition of acceptance.

• Right now it seems that the problem of “acceptAll” is fixed.

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Dimuon Vertex in z

Target Beam dump

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/usrX/wchang/E906/Root/ accept_all.cc

void accept_xfmass(){ // open the ROOT ntuple TFile* f = new TFile("/sp8data11/shyao/rootfile/r321test.root","READ"); TTree* event = f->Get("event");//define the cuts TCut *target = new TCut("z0[0]<0 && z0[1] <0"); TCut *bmdump = new TCut("z0[0]>0 && z0[1] >0"); TCut *accept = new

TCut("hitSt4[0]*hitSt3[0]*hitSt2[0]*hitSt1[0]*hitSt4[1]*hitSt3[1]*hitSt2[1]*hitSt1[1]>0");

//create the Canvas for plotting TCanvas* c1 = new TCanvas("c1","canvas title",1200,900); c1->Divide(2,2); //book the histrograms TH2F *gen = new TH2F("gen","generated events",20,0,10,20,-1,1); TH2F *acp = new TH2F("acp","accepted events",20,0,10,20,-1,1); TH2F *eff = new TH2F("eff","efficiency",20,0,10,20,-1,1);//place the labeling of axises gen->GetXaxis()->SetTitle("mass"); gen->GetYaxis()->SetTitle("xf"); acp->GetXaxis()->SetTitle("mass"); acp->GetYaxis()->SetTitle("xf"); eff->GetXaxis()->SetTitle("mass"); eff->GetYaxis()->SetTitle("xf"); eff->GetZaxis()->SetTitle("Efficency");

// plot the figures one by one c1->cd(1); event->Draw("xf:mass>>gen", *target); c1->cd(2); event->Draw("xf:mass>>acp", *target && *accept); eff->Divide(acp, gen, 1., 1., "b"); // getting efficiency c1->cd(3); eff->Draw("cont"); c1->cd(4); eff->Draw("lego");// Output the plots as eps or jpg files c1->Print("eff_xfmass.eps"); c1->Print("eff_xfmass.jpg"); //Save the Canvas and histrograms into a file TFile *picf = new TFile("./acpt_xfmass.root","RECREATE"); c1->Write(); gen->Write(); acp->Write(); eff->Write(); picf->Close();//close the ROOT ntuple f->Close();}

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Acceptance in “mass”

Events of J/psi and DY.

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Acceptance in “xf”

Somehow the acceptance in xf is rather flat.?

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Acceptance in “xf vs. mass”

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Acceptance in “x1”

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Acceptance in “x2”

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Acceptance in “x2 vs. x1”

Good acceptance in large x1 (beam) and small x2 (target).

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Acceptance in “phi_mu”

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Acceptance in “cos(theta_mu)”

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Acceptance in “phi_my vs. cos(theta_mu)”

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Conclusion

• The ROOT ntuple with the event-loop structure is easier for analysis. I urge the students to do the exercise ASAP.

• PAW to ROOT conversion table: http://root.cern.ch/root/HowtoConvertFromPAW.html .

• I have to admit that there is a non-negligible threshold of being experienced with ROOT for those who started with PAW for analysis. (I echo the comment given in http://qd.typepad.com/4/2005/08/i_hate_root.html .)

• For the consideration of being competitive in data analysis for people with ages >40 like me, it will be very much appreciated if 姚錫弘 could also convert the MySQL tables into a PAW ntuple file with an event-loop structure.