1 void tzero15tracks(const char* datafile, Float_t globalTimeRes=1.2e-10)
5 // Calculate the t0 distribution
7 // (primary particles reaching TOF)
8 // NB: see the description of the analogous AliTOFT0 class
9 // NB II: apply this macro to a realistic Pb-Pb event (e.g. Hijing event)
12 // root [0] .L tzero15tracksopt.C
13 // // exec the macro with the default time resolution 120 ps
14 // root [1] tzero15tracksopt("hij25evCentralTOFv4T0Set10.04T.root")
16 // // exec the macro with 150 ps global time resolution
17 // // NB: time resolution has to be given in [s]
18 // root [1] tzero15tracksopt("hij25evCentralTOFv4T0Set10.04T.root", 1.5e-10))
21 // Dynamically link some shared libs
22 if (gClassTable->GetID("AliRun") < 0) {
23 gROOT->LoadMacro("loadlibs.C");
27 // Connect the Root Galice file containing Geometry, Kine and Hits
29 Int_t nmisidentified=0;
30 Int_t nmisidentified0=0;
31 Int_t nmisidentified1=0;
32 Int_t nmisidentified2=0;
33 Int_t nmisidentified3=0;
34 Int_t nmisidentified4=0;
35 Int_t nmisidentified5=0;
36 Int_t nmisidentified6=0;
37 Int_t nmisidentified7=0;
38 Int_t nmisidentified8=0;
39 Int_t nmisidentified9=0;
40 Int_t nmisidentified10=0;
41 Int_t nmisidentified11=0;
42 Int_t nmisidentified12=0;
43 Int_t nmisidentified13=0;
44 Int_t nmisidentified14=0;
52 const Float_t timeresolution=globalTimeRes; // in [s]
53 Float_t timeresolutioninns=timeresolution*(1.e+9); // convert in [ns]
54 cout << "Global Time Resolution " << timeresolutioninns << " ns" << endl; //
56 // output (histos!) filename
57 char outFileName[100];
58 strcpy(outFileName,"ht015tr");
59 strcat(outFileName,datafile);
61 gBenchmark->Start("TOFT0");
63 TH1F* htzerobest= new TH1F("htzerobest","T0 for best assignment",200,-1.,1.);
64 TH1F* hchibest = new TH1F("hchibest","ChiSquare Min Distribution",80,0.,40.);
65 TH1F* hchibestconflevel = new TH1F("hchibestconflevel","ChiSquare Min Confidence Level",10,0.,1.);
68 Int_t assparticle[15]={3,3,3,3,3,3,3,3,3,3,3,3,3,3,3};
69 Int_t truparticle[15]={3,3,3,3,3,3,3,3,3,3,3,3,3,3,3};
70 Float_t timeofflight[15]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
71 Float_t momentum[15]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
73 Float_t weightedtimezero[15];
74 Float_t beta[15]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
75 Float_t sqMomError[15]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
76 Float_t sqTrackError[15]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
77 Float_t massarray[3]={0.13957,0.493677,0.9382723};
78 Float_t chisquare=999.;
79 Float_t tracktoflen[15]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
80 TRandom* rnd = new TRandom();
84 TFile *file = TFile::Open(datafile,"old");
86 // Get AliRun object from file or create it if not on file
87 gAlice = (AliRun*)file->Get("gAlice");
89 // Import the Kine and Hits Trees for the event evNumber in the file
91 Int_t nallevents = (Int_t) gAlice->TreeE()->GetEntries();
93 for (Int_t nev=0; nev<nallevents;nev++) {
95 Int_t nparticles = gAlice->GetEvent(nev);
96 if (nparticles <= 0) return;
98 // Get pointers to Alice detectors and Hits containers
100 AliDetector *TOF = gAlice->GetDetector("TOF");
101 TObjArray *Particles = gAlice->Particles();
103 if (TOF) TClonesArray *TOFhits = TOF->Hits();
105 TTree *TH = gAlice->TreeH();
106 Int_t ntracks = TH->GetEntries();
109 // Start loop on primary tracks in the hits containers
112 for (Int_t track=lasttrack+1; track<ntracks;track++) {
114 if(nset>=3) break; // check on the number of set analyzed
117 nbytes += TH->GetEvent(track);
119 // =======>Histogram TOF
121 nhits = TOFhits->GetEntriesFast();
123 for (hit=0;hit<nhits;hit++) {
125 tofHit = (AliTOFhitT0*)TOFhits->UncheckedAt(hit);
126 ipart = tofHit->GetTrack();
128 // check to discard the case when the same particle is selected more than one
131 if (ipart != ipartold){
133 particle = (TParticle*)gAlice->Particle(ipart);
135 Float_t idealtime=tofHit->GetTof();
136 // Float_t time=idealtime;
137 Float_t time = rnd->Gaus(idealtime, timeresolution);
138 Float_t toflen=tofHit->GetLen();
139 toflen=toflen/100.; // toflen given in m because GEANT gives cm!
140 Int_t pdg = particle->GetPdgCode();
141 Int_t abspdg =TMath::Abs(pdg);
142 Float_t idealmom = particle->P();
143 Float_t momres=idealmom*0.025; // 2.5% res token into account for all momenta
144 //Float_t mom =idealmom+2.*(rnd->Rndm()-0.5)*momres;
145 Float_t mom =rnd->Gaus(idealmom,momres);
146 Bool_t isgoodpart=(abspdg==211 || abspdg==2212 || abspdg==321);
148 time*=1.e+9; // tof given in nanoseconds
149 if (particle->GetFirstMother() < 0 && isgoodpart && mom<=1.75 && mom>=1.25){
154 Int_t index=selected-1;
155 timeofflight[index]=time;
156 tracktoflen[index]=toflen;
160 truparticle[index]=0;
163 truparticle[index]=1;
166 truparticle[index]=2;
173 if(istop==15){ // start analysis on current set
178 cout << "starting t0 calculation for current set" << endl;
179 for (Int_t i1=0; i1<3;i1++) {
180 beta[0]=momentum[0]/TMath::Sqrt(massarray[i1]*massarray[i1]+momentum[0]*momentum[0]);
181 for (Int_t i2=0; i2<3;i2++) {
182 beta[1]=momentum[1]/TMath::Sqrt(massarray[i2]*massarray[i2]+momentum[1]*momentum[1]);
183 for (Int_t i3=0; i3<3;i3++) {
184 beta[2]=momentum[2]/TMath::Sqrt(massarray[i3]*massarray[i3]+momentum[2]*momentum[2]);
185 for (Int_t i4=0; i4<3;i4++) {
186 beta[3]=momentum[3]/TMath::Sqrt(massarray[i4]*massarray[i4]+momentum[3]*momentum[3]);
187 for (Int_t i5=0; i5<3;i5++) {
188 beta[4]=momentum[4]/TMath::Sqrt(massarray[i5]*massarray[i5]+momentum[4]*momentum[4]);
189 for (Int_t i6=0; i6<3;i6++) {
190 beta[5]=momentum[5]/TMath::Sqrt(massarray[i6]*massarray[i6]+momentum[5]*momentum[5]);
191 for (Int_t i7=0; i7<3;i7++) {
192 beta[6]=momentum[6]/TMath::Sqrt(massarray[i7]*massarray[i7]+momentum[6]*momentum[6]);
193 for (Int_t i8=0; i8<3;i8++) {
194 beta[7]=momentum[7]/TMath::Sqrt(massarray[i8]*massarray[i8]+momentum[7]*momentum[7]);
195 for (Int_t i9=0; i9<3;i9++) {
196 beta[8]=momentum[8]/TMath::Sqrt(massarray[i9]*massarray[i9]+momentum[8]*momentum[8]);
197 for (Int_t i10=0; i10<3;i10++) {
198 beta[9]=momentum[9]/TMath::Sqrt(massarray[i10]*massarray[i10]+momentum[9]*momentum[9]);
199 for (Int_t i11=0; i11<3;i11++) {
200 beta[10]=momentum[10]/TMath::Sqrt(massarray[i11]*massarray[i11]+momentum[10]*momentum[10]);
201 for (Int_t i12=0; i12<3;i12++) {
202 beta[11]=momentum[11]/TMath::Sqrt(massarray[i12]*massarray[i12]+momentum[11]*momentum[11]);
203 for (Int_t i13=0; i13<3;i13++) {
204 beta[12]=momentum[12]/TMath::Sqrt(massarray[i13]*massarray[i13]+momentum[12]*momentum[12]);
205 for (Int_t i14=0; i14<3;i14++) {
206 beta[13]=momentum[13]/TMath::Sqrt(massarray[i14]*massarray[i14]+momentum[13]*momentum[13]);
207 for (Int_t i15=0; i15<3;i15++) {
208 beta[14]=momentum[14]/TMath::Sqrt(massarray[i15]*massarray[i15]+momentum[14]*momentum[14]);
210 Float_t meantzero=0.;
211 Float_t sumAllweights=0.;
212 for (Int_t itz=0; itz<15;itz++) {
213 sqMomError[itz]=((1.-beta[itz]*beta[itz])*0.025)*((1.-beta[itz]*beta[itz])*0.025)*(tracktoflen[itz]/(0.299792*beta[itz]))*(tracktoflen[itz]/(0.299792*beta[itz])); // this gives the square of the momentum error in nanoseconds
214 sqTrackError[itz]=(timeresolutioninns*timeresolutioninns+sqMomError[itz]); // total error for the current track
215 sumAllweights+=1./sqTrackError[itz];
216 timezero[itz]=(tracktoflen[itz]/(beta[itz]*0.299792))-timeofflight[itz];
217 weightedtimezero[itz]=((tracktoflen[itz]/(beta[itz]*0.299792))-timeofflight[itz])/sqTrackError[itz];// weighted time zero for current track
218 meantzero+=weightedtimezero[itz];
221 meantzero=meantzero/sumAllweights; // it is given in [ns]
223 Float_t dummychisquare=0.;
224 // calculate the chisquare for the current assignment
225 for (Int_t itz=0; itz<15;itz++) {
226 dummychisquare+=(timezero[itz]-meantzero)*(timezero[itz]-meantzero)/sqTrackError[itz];
230 if(dummychisquare<=chisquare){
246 chisquare=dummychisquare;
266 cout << "true" << truparticle[0] << truparticle[1] << truparticle[2] << truparticle[3] << truparticle[4] << truparticle[5] << truparticle[6] << truparticle[7] << truparticle[8] << truparticle[9] <<truparticle[10] << truparticle[11] << truparticle[1
267 2] << truparticle[13] << truparticle[14] <<endl;
268 cout << "best" << assparticle[0] << assparticle[1] << assparticle[2] << assparticle[3] << assparticle[4] << assparticle[5] << assparticle[6] << assparticle[7] << assparticle[8] << assparticle[9] <<assparticle[10] << assparticle[11] << assparticle[1
269 2] << assparticle[13] << assparticle[14] << endl;
270 if(truparticle[0]==assparticle[0] && truparticle[1]==assparticle[1] && truparticle[2]==assparticle[2] && truparticle[3]==assparticle[3] && truparticle[4]==assparticle[4]&& truparticle[5]==assparticle[5] && truparticle[6]==assparticle[6] && trupart
271 icle[7]==assparticle[7] && truparticle[8]==assparticle[8] && truparticle[9]==assparticle[9] &&truparticle[10]==assparticle[10] && truparticle[11]==assparticle[11] && truparticle[12]==assparticle[12] && truparticle[13]==assparticle[13] && truparticle[14]
272 ==assparticle[14]) ngood+=1;
273 if(truparticle[0]!=assparticle[0]) nmisidentified0+=1;
274 if(truparticle[1]!=assparticle[1]) nmisidentified1+=1;
275 if(truparticle[2]!=assparticle[2]) nmisidentified2+=1;
276 if(truparticle[3]!=assparticle[3]) nmisidentified3+=1;
277 if(truparticle[4]!=assparticle[4]) nmisidentified4+=1;
278 if(truparticle[5]!=assparticle[5]) nmisidentified5+=1;
279 if(truparticle[6]!=assparticle[6]) nmisidentified6+=1;
280 if(truparticle[7]!=assparticle[7]) nmisidentified7+=1;
281 if(truparticle[8]!=assparticle[8]) nmisidentified8+=1;
282 if(truparticle[9]!=assparticle[9]) nmisidentified9+=1;
283 if(truparticle[10]!=assparticle[10]) nmisidentified10+=1;
284 if(truparticle[11]!=assparticle[11]) nmisidentified11+=1;
285 if(truparticle[12]!=assparticle[12]) nmisidentified12+=1;
286 if(truparticle[13]!=assparticle[13]) nmisidentified13+=1;
287 if(truparticle[14]!=assparticle[14]) nmisidentified14+=1;
288 cout << "chisquare for current set" << chisquare << endl;
289 htzerobest->Fill(t0best);
290 hchibest->Fill(chisquare);
291 Double_t dblechisquare=(Double_t)chisquare;
292 Float_t confLevel=(Float_t)TMath::Prob(dblechisquare,14);
293 cout << "conf level " << confLevel << endl;
294 hchibestconflevel->Fill(confLevel);
298 } // end for the current set. close if(istop==15)
301 } // end condition on ipartold
304 }// end loop on hits for the current track
307 }// end loop on Tracks
308 cout << "ngood for current event " << ngood << endl;
311 }//end loop on events
313 nmisidentified=(nmisidentified0+nmisidentified1+nmisidentified2+nmisidentified3+nmisidentified4+nmisidentified5+nmisidentified6+nmisidentified7+nmisidentified8+nmisidentified9+nmisidentified10+nmisidentified11+nmisidentified12+nmisidentified13+nmisident
315 cout << "total misidentified " << nmisidentified << endl;
316 TFile *houtfile = new TFile(outFileName,"recreate");
321 hchibestconflevel->Write();
324 gBenchmark->Stop("TOFT0");
325 cout << "15 tracks:" << endl ;
326 cout << " took " << gBenchmark->GetCpuTime("TOFT0") << " seconds in order to calculate T0 "
327 << gBenchmark->GetCpuTime("TOFT0")/nallevents << " seconds per event " << endl ;