TOF/AliTOFT0.cxx

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  15
  16 /* $Id$ */
  17
  18 //_________________________________________________________________________
  19 //
  20 // This is a TTask that made the calculation of the Time zero using TOF.
  21 // Description: The algorithm used to calculate the time zero of
  22 // interaction using TOF detector is the following.
  23 // We select in the MonteCarlo some primary particles - or tracks in
  24 // the following - that strike the TOF detector (the larger part are
  25 // pions, kaons or protons).
  26 // We choose a set of 10 selected tracks, for each track You have the
  27 // length of the track when the TOF is reached (a standard TOF hit
  28 // does not contain this additional information, this is the reason
  29 // why we implemented a new time zero dedicated TOF hit class
  30 // AliTOFhitT0; in order to store this type of hit You have to use the
  31 // AliTOFv4T0 as TOF class in Your Config.C. In AliTOFv4T0 the
  32 // StepManager was modified in order to fill the TOF hit branch with
  33 // this type of hits; in fact the AliTOF::AddT0Hit is called rather
  34 // that the usual AliTOF::AddHit), the momentum at generation (from
  35 // TreeK) and the time of flight given by the TOF detector.
  36 // (Observe that the ctor of the AliTOF class, when the AliTOFv4T0
  37 // class is used, is called with the "tzero" option: it is in order
  38 // create the fHits TClonesArray filled with AliTOFhitT0 objects,
  39 // rather than with normal AliTOFhit)
  40 // Then Momentum and time of flight for each track are smeared
  41 // according to known experimental resolution (all sources of error
  42 // have been token into account).
  43 // Let consider now only one set of 10 tracks (the algorithm is the
  44 // same for all sets).
  45 // Assuming the (mass) hypothesis that each track can be AUT a pion,
  46 // AUT a kaon, AUT a proton, we consider all the 3 at 10 possible
  47 // cases.
  48 // For each track in each (mass) configuration
  49 // (a configuration can be
  50 // e.g. pion/pion/kaon/proton/pion/proton/kaon/kaon/pion/pion)
  51 // we calculate the time zero (we know in fact the velocity of the
  52 // track after the assumption about its mass, the time of flight given
  53 // by the TOF, and the corresponding path travelled till the TOF
  54 // detector). Then for each mass configuration we have 10 time zero
  55 // and we can calculate the ChiSquare for the current configuration
  56 // using the weighted mean over all 10 time zero.
  57 // We call the best assignment the mass configuration that gives the
  58 // minimum value of the ChiSquare.
  59 // We plot the weighted mean over all 10 time zero for the best
  60 // assignment, the ChiSquare for the best assignment and the
  61 // corresponding confidence level.
  62 // The strong assumption is the MC selection of primary particles. It
  63 // will be introduced in the future also some more realistic
  64 // simulation about this point.
  65 //
  66 // Use case:
  67 // root [0] AliTOFT0 * tzero = new AliTOFT0("galice.root")
  68 // Warning in <TDatabasePDG::TDatabasePDG>: object already instantiated
  69 // root [1] tzero->ExecuteTask()
  70 // root [2] tzero->ExecuteTask("tim")
  71 //             // available parameters:
  72 //             tim - print benchmarking information
  73 //             all - print usefull informations about the number of
  74 //                   misidentified tracks and a comparison about the
  75 //                   true configuration (known from MC) and the best
  76 //                   assignment
  77 //
  78 //-- Author: F. Pierella
  79 //
  80 //_________________________________________________________________________
  81
  82 #include <TCanvas.h>
  83 #include <TClonesArray.h>
  84 #include <TFile.h>
  85 //#include <TFolder.h>
  86 #include <TFrame.h>
  87 #include <TH1.h>
  88 #include <TParticle.h>
  89 #include <TBenchmark.h>
  90 #include <TTask.h>
  91 #include <TTree.h>
  92 #include <TRandom.h>
  93 #include <TROOT.h>
  94
  95 #include "AliMC.h"
  96 #include "AliRun.h"
  97
  98 #include "AliTOFhitT0.h"
  99 #include "AliTOFT0.h"
 100 #include "AliTOF.h"
 101
 102 extern TROOT *gROOT;
 103 extern TRandom *gRandom;
 104 extern TBenchmark *gBenchmark;
 105
 106 extern AliRun *gAlice;
 107
 108 ClassImp(AliTOFT0)
 109
 110 //____________________________________________________________________________
 111 AliTOFT0::AliTOFT0():
 112   TTask("AliTOFT0",""),
 113   fNevents(0),
 114   fTimeResolution(0),
 115   fLowerMomBound(0),
 116   fUpperMomBound(0),
 117   fT0File(""),
 118   fHeadersFile("")
 119 {
 120   // ctor
 121 }
 122
 123 //____________________________________________________________________________
 124 AliTOFT0::AliTOFT0(char* headerFile, Int_t nEvents):
 125   TTask("AliTOFT0",""),
 126   fNevents(nEvents),
 127   fTimeResolution(1.2e-10),
 128   fLowerMomBound(1.5),
 129   fUpperMomBound(2.),
 130   fT0File(""),
 131   fHeadersFile(headerFile)
 132 {
 133   //
 134   //
 135   //
 136
 137   //fNevents=nEvents ; // Number of events for which calculate the T0,
 138                      // default 0: it means all evens in current file
 139   //fLowerMomBound=1.5; // [GeV/c] default value
 140   //fUpperMomBound=2. ; // [GeV/c] default value
 141   //fTimeResolution   = 1.2e-10; // 120 ps by default
 142   //fHeadersFile = headerFile ;
 143
 144   TFile * file = (TFile*) gROOT->GetFile(fHeadersFile.Data() ) ;
 145
 146   //File was not opened yet
 147   if(file == 0){
 148     if(fHeadersFile.Contains("rfio"))
 149       file =    TFile::Open(fHeadersFile,"update") ;
 150     else
 151       file = new TFile(fHeadersFile.Data(),"update") ;
 152     gAlice = (AliRun *) file->Get("gAlice") ;
 153   }
 154
 155   // add Task to //root/Tasks folder
 156   TTask * roottasks = (TTask*)gROOT->GetRootFolder()->FindObject("Tasks") ;
 157   roottasks->Add(this) ;
 158 }
 159
 160 //____________________________________________________________________________
 161 AliTOFT0::AliTOFT0(const AliTOFT0 & tzero):
 162   TTask("AliTOFT0",""),
 163   fNevents(0),
 164   fTimeResolution(0),
 165   fLowerMomBound(0),
 166   fUpperMomBound(0),
 167   fT0File(""),
 168   fHeadersFile("")
 169 {
 170   // copy ctr
 171
 172 ( (AliTOFT0 &)tzero ).Copy(*this);
 173 }
 174
 175 //____________________________________________________________________________
 176   AliTOFT0::~AliTOFT0()
 177 {
 178   // dtor
 179 }
 180
 181 //____________________________________________________________________________
 182 void AliTOFT0::Exec(Option_t *option)
 183 {
 184   //
 185   // calculate T0 distribution for all events using chisquare
 186   //
 187   Int_t ngood=0;
 188   Int_t nmisidentified=0;
 189   Int_t nmisidentified0=0;
 190   Int_t nmisidentified1=0;
 191   Int_t nmisidentified2=0;
 192   Int_t nmisidentified3=0;
 193   Int_t nmisidentified4=0;
 194   Int_t nmisidentified5=0;
 195   Int_t nmisidentified6=0;
 196   Int_t nmisidentified7=0;
 197   Int_t nmisidentified8=0;
 198   Int_t nmisidentified9=0;
 199   Int_t ipartold = -1;
 200   Int_t ipart;
 201   Int_t selected=0;
 202   Int_t istop=0;
 203   Float_t timeresolutioninns=fTimeResolution*(1.e+9); // convert in [ns]
 204   const Int_t kUPDATE = 5; // for visual option
 205   Int_t itimes=0;
 206   TCanvas* c1=0;
 207   TCanvas* c2=0;
 208   TCanvas* c3=0;
 209
 210   if(strstr(option,"visual")){
 211     // Create a new canvas.
 212     //c1 = new TCanvas("c1","Dynamic Visual Filling of time zero histo",10,10,500,500);
 213     c1 = new TCanvas("c1","Dynamic Visual Filling of time zero histo",10,10,370,370);
 214     c1->SetFillColor(35);
 215     c1->GetFrame()->SetFillColor(21);
 216     c1->GetFrame()->SetBorderSize(6);
 217     c1->GetFrame()->SetBorderMode(-1);
 218
 219     //c2 = new TCanvas("c2","Dynamic Visual Filling of chisquare histo",550,10,500,500);
 220     c2 = new TCanvas("c2","Dynamic Visual Filling of chisquare histo",380,10,370,370);
 221     c2->SetFillColor(35);
 222     c2->GetFrame()->SetFillColor(21);
 223     c2->GetFrame()->SetBorderSize(6);
 224     c2->GetFrame()->SetBorderMode(-1);
 225
 226     //c3 = new TCanvas("c3","Dynamic Visual Filling of confidence level histo",280,550,500,500);
 227     c3 = new TCanvas("c3","Dynamic Visual Filling of confidence level histo",760,10,370,370);
 228     c3->SetFillColor(35);
 229     c3->GetFrame()->SetFillColor(21);
 230     c3->GetFrame()->SetBorderSize(6);
 231     c3->GetFrame()->SetBorderMode(-1);
 232   }
 233
 234   if(strstr(option,"tim") || strstr(option,"all"))
 235     gBenchmark->Start("TOFT0");
 236
 237   TH1F *htzerobest= new TH1F("htzerobest","T0 for best assignment",200,-1.,1.);
 238   TH1F* hchibest  = new TH1F("hchibest","ChiSquare Min Distribution",80,0.,40.);
 239   TH1F* hchibestconflevel  = new TH1F("hchibestconflevel","ChiSquare Min Confidence Level",10,0.,1.);
 240
 241   // setting histo colors
 242   if(strstr(option,"visual")){
 243     htzerobest->SetFillColor(48);
 244     hchibest->SetFillColor(50);
 245     hchibestconflevel->SetFillColor(52);
 246   }
 247
 248   Int_t   assparticle[10]={3,3,3,3,3,3,3,3,3,3};
 249   Int_t   truparticle[10]={3,3,3,3,3,3,3,3,3,3};
 250   Float_t t0best=999.;
 251   Float_t timeofflight[10]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
 252   Float_t momentum[10]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
 253   Float_t timezero[10];
 254   Float_t weightedtimezero[10];
 255   Float_t beta[10]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
 256   Float_t sqMomError[10]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
 257   Float_t sqTrackError[10]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
 258   Float_t massarray[3]={0.13957,0.493677,0.9382723};
 259   Float_t dummychisquare=0.;
 260   Float_t chisquare=999.;
 261   Float_t tracktoflen[10]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
 262
 263   AliTOF *detTOF = (AliTOF *) gAlice->GetDetector ("TOF");
 264
 265   if (!detTOF) {
 266     Error("AliTOFT0","TOF not found");
 267     return;
 268   }
 269
 270   if(strstr(option,"all")){
 271     AliInfo(Form("Selecting primary tracks with momentum between %f GeV/c and %f GeV/c",  fLowerMomBound, fUpperMomBound));
 272     AliInfo("Memorandum: 0 means PION | 1 means KAON | 2 means PROTON")
 273   }
 274
 275   if (fNevents == 0) fNevents = (Int_t) AliRunLoader::Instance()->TreeE()->GetEntries();
 276
 277   for (Int_t ievent = 0; ievent < fNevents; ievent++) {
 278     gAlice->GetEvent(ievent);
 279     TTree *hitTree = detTOF->GetLoader()->TreeH ();
 280     if (!hitTree)
 281       return;
 282     TParticle*    particle;
 283     AliTOFhitT0*  tofHit;
 284     TClonesArray* tofHits = detTOF->Hits();
 285
 286     Int_t lasttrack=-1;
 287     Int_t nset=0;
 288
 289     hitTree->SetBranchStatus("*",0); // switch off all branches
 290     hitTree->SetBranchStatus("TOF*",1); // switch on only TOF
 291
 292     // Start loop on primary tracks in the hits containers
 293
 294     Int_t ntracks = static_cast<Int_t>(hitTree->GetEntries());
 295     for (Int_t track = 0; track < ntracks; track++)
 296     {
 297       if(nset>=5) break; // check on the number of set analyzed
 298
 299       gAlice->GetMCApp()->ResetHits();
 300       hitTree->GetEvent(track);
 301
 302       //AliMC *mcApplication = (AliMC*)gAlice->GetMCApp();
 303
 304       //particle = mcApplication->Particle(track);
 305       Int_t nhits = tofHits->GetEntriesFast();
 306
 307       for (Int_t hit = 0; hit < nhits; hit++)
 308       {
 309         tofHit = (AliTOFhitT0 *) tofHits->UncheckedAt(hit);
 310         ipart    = tofHit->GetTrack();
 311         // check to discard the case when the same particle is selected more than one
 312         // time
 313
 314         if (ipart != ipartold){
 315
 316           particle = (TParticle*)gAlice->GetMCApp()->Particle(ipart);
 317
 318           Float_t idealtime=tofHit->GetTof();
 319           //       Float_t time=idealtime;
 320           Float_t time   = gRandom->Gaus(idealtime, fTimeResolution);
 321           Float_t toflen=tofHit->GetLen();
 322           toflen=toflen/100.; // toflen given in m
 323           Int_t pdg   = particle->GetPdgCode();
 324           Int_t abspdg   =TMath::Abs(pdg);
 325           Float_t idealmom  = particle->P();
 326           Float_t momres=idealmom*0.025; // 2.5% res token into account for all momenta
 327           Float_t mom =gRandom->Gaus(idealmom,momres);
 328
 329           Bool_t isgoodpart=(abspdg==211 || abspdg==2212 || abspdg==321);
 330
 331           time*=1.E+9; // tof given in nanoseconds
 332           if (particle->GetFirstMother() < 0 && isgoodpart && mom<=fUpperMomBound && mom>=fLowerMomBound){
 333             selected+=1;
 334             istop=selected;
 335             if(istop>10) break;
 336             Int_t index=selected-1;
 337             timeofflight[index]=time;
 338             tracktoflen[index]=toflen;
 339             momentum[index]=mom;
 340             //AliInfo(Form(" %d  %d  %d ", timeofflight[index], tracktoflen[index], momentum[index]));
 341             switch (abspdg) {
 342             case 211:
 343               truparticle[index]=0;
 344               break ;
 345             case 321:
 346               truparticle[index]=1;
 347               break ;
 348             case 2212:
 349               truparticle[index]=2;
 350               break ;
 351             }
 352
 353           }
 354           ipartold = ipart;
 355
 356           if(istop==10){ // start analysis on current set
 357             nset+=1;
 358             lasttrack=track;
 359             istop=0;
 360             selected=0;
 361             //AliInfo("starting t0 calculation for current set");
 362             for (Int_t i1=0; i1<3;i1++) {
 363               beta[0]=momentum[0]/sqrt(massarray[i1]*massarray[i1]+momentum[0]*momentum[0]);
 364               for (Int_t i2=0; i2<3;i2++) {
 365                 beta[1]=momentum[1]/sqrt(massarray[i2]*massarray[i2]+momentum[1]*momentum[1]);
 366                 for (Int_t i3=0; i3<3;i3++) {
 367                   beta[2]=momentum[2]/sqrt(massarray[i3]*massarray[i3]+momentum[2]*momentum[2]);
 368                   for (Int_t i4=0; i4<3;i4++) {
 369                     beta[3]=momentum[3]/sqrt(massarray[i4]*massarray[i4]+momentum[3]*momentum[3]);
 370                     for (Int_t i5=0; i5<3;i5++) {
 371                       beta[4]=momentum[4]/sqrt(massarray[i5]*massarray[i5]+momentum[4]*momentum[4]);
 372                       for (Int_t i6=0; i6<3;i6++) {
 373                         beta[5]=momentum[5]/sqrt(massarray[i6]*massarray[i6]+momentum[5]*momentum[5]);
 374                         for (Int_t i7=0; i7<3;i7++) {
 375                           beta[6]=momentum[6]/sqrt(massarray[i7]*massarray[i7]+momentum[6]*momentum[6]);
 376                           for (Int_t i8=0; i8<3;i8++) {
 377                             beta[7]=momentum[7]/sqrt(massarray[i8]*massarray[i8]+momentum[7]*momentum[7]);
 378                             for (Int_t i9=0; i9<3;i9++) {
 379                               beta[8]=momentum[8]/sqrt(massarray[i9]*massarray[i9]+momentum[8]*momentum[8]);
 380                               for (Int_t i10=0; i10<3;i10++) {
 381                                 beta[9]=momentum[9]/sqrt(massarray[i10]*massarray[i10]+momentum[9]*momentum[9]);
 382
 383                                 Float_t meantzero=0.;
 384                                 Float_t sumAllweights=0.;
 385                                 for (Int_t itz=0; itz<10;itz++) {
 386                                   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
 387                                   sqTrackError[itz]=(timeresolutioninns*timeresolutioninns+sqMomError[itz]); // total error for the current track
 388                                   sumAllweights+=1./sqTrackError[itz];
 389
 390                                   timezero[itz]=(tracktoflen[itz]/(beta[itz]*0.299792))-timeofflight[itz];
 391                                   weightedtimezero[itz]=((tracktoflen[itz]/(beta[itz]*0.299792))-timeofflight[itz])/sqTrackError[itz];// weighted time zero for current track
 392                                   meantzero+=weightedtimezero[itz];
 393                                 } // end loop for (Int_t itz=0; itz<10;itz++)
 394                                 meantzero=meantzero/sumAllweights; // it is given in [ns]
 395
 396                                 dummychisquare=0.;
 397                                 // calculate the chisquare for the current assignment
 398                                 for (Int_t icsq=0; icsq<10;icsq++) {
 399                                   dummychisquare+=(timezero[icsq]-meantzero)*(timezero[icsq]-meantzero)/sqTrackError[icsq];
 400                                 } // end loop for (Int_t icsq=0; icsq<10;icsq++)
 401
 402                                 if(dummychisquare<=chisquare){
 403                                   assparticle[0]=i1;
 404                                   assparticle[1]=i2;
 405                                   assparticle[2]=i3;
 406                                   assparticle[3]=i4;
 407                                   assparticle[4]=i5;
 408                                   assparticle[5]=i6;
 409                                   assparticle[6]=i7;
 410                                   assparticle[7]=i8;
 411                                   assparticle[8]=i9;
 412                                   assparticle[9]=i10;
 413                                   chisquare=dummychisquare;
 414                                   t0best=meantzero;
 415                                 } // close if(dummychisquare<=chisquare)
 416
 417                               } // end loop on i10
 418                             } // end loop on i9
 419                           } // end loop on i8
 420                         } // end loop on i7
 421                       } // end loop on i6
 422                     } // end loop on i5
 423                   } // end loop on i4
 424                 } // end loop on i3
 425               } // end loop on i2
 426             } // end loop on i1
 427
 428             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] && truparticle[7]==assparticle[7]  && truparticle[8]==assparticle[8] && truparticle[9]==assparticle[9]) ngood+=1;
 429             if(truparticle[0]!=assparticle[0]) nmisidentified0+=1;
 430             if(truparticle[1]!=assparticle[1]) nmisidentified1+=1;
 431             if(truparticle[2]!=assparticle[2]) nmisidentified2+=1;
 432             if(truparticle[3]!=assparticle[3]) nmisidentified3+=1;
 433             if(truparticle[4]!=assparticle[4]) nmisidentified4+=1;
 434             if(truparticle[5]!=assparticle[5]) nmisidentified5+=1;
 435             if(truparticle[6]!=assparticle[6]) nmisidentified6+=1;
 436             if(truparticle[7]!=assparticle[7]) nmisidentified7+=1;
 437             if(truparticle[8]!=assparticle[8]) nmisidentified8+=1;
 438             if(truparticle[9]!=assparticle[9]) nmisidentified9+=1;
 439             // filling histos
 440             htzerobest->Fill(t0best);
 441             hchibest->Fill(chisquare);
 442             Double_t dblechisquare=(Double_t)chisquare;
 443             Float_t confLevel=(Float_t)TMath::Prob(dblechisquare,9); // ndf 10-1=9
 444             hchibestconflevel->Fill(confLevel);
 445             itimes++;
 446             if(strstr(option,"all")){
 447               AliInfo(Form("True Assignment %d  %d  %d  %d  %d  %d  %d  %d  %d  %d", truparticle[0], truparticle[1], truparticle[2], truparticle[3], truparticle[4], truparticle[5], truparticle[6], truparticle[7], truparticle[8], truparticle[9]));
 448               AliInfo(Form("Best Assignment %d  %d  %d  %d  %d  %d  %d  %d  %d  %d", assparticle[0], assparticle[1], assparticle[2], assparticle[3], assparticle[4], assparticle[5], assparticle[6], assparticle[7], assparticle[8], assparticle[9]));
 449               AliInfo(Form("Minimum ChiSquare for current set   %f ", chisquare));
 450               AliInfo(Form("Confidence Level (Minimum ChiSquare) %f", confLevel));
 451             }
 452             if (strstr(option,"visual") && itimes && (itimes%kUPDATE) == 0) {
 453               if (itimes == kUPDATE){
 454                 c1->cd();
 455                 htzerobest->Draw();
 456                 c2->cd();
 457                 hchibest->Draw();
 458                 c3->cd();
 459                 hchibestconflevel->Draw();
 460               }
 461               c1->Modified();
 462               c1->Update();
 463               c2->Modified();
 464               c2->Update();
 465               c3->Modified();
 466               c3->Update();
 467               if (gSystem->ProcessEvents())
 468                 break;
 469             }
 470             chisquare=999.;
 471             t0best=999.;
 472
 473           } // end for the current set. close if(istop==5)
 474         } // end condition on ipartold
 475       } // end loop on hits for the current track
 476       if(istop>=10) break;
 477     } // end loop on ntracks
 478   } //event loop
 479
 480   if(strstr(option,"all")){
 481     nmisidentified=(nmisidentified0+nmisidentified1+nmisidentified2+nmisidentified3+nmisidentified4+nmisidentified5+nmisidentified6+nmisidentified7+nmisidentified8+nmisidentified9);
 482     AliInfo(Form("total number of tracks token into account  %i", 10*5*fNevents));
 483     Float_t badPercentage=100.*(Float_t)nmisidentified/(10*5*fNevents);
 484     AliInfo(Form("total misidentified                       %i (%f %%) ", nmisidentified, badPercentage));
 485     AliInfo(Form("Total Number of set token into account     %i", 5*fNevents));
 486     Float_t goodSetPercentage=100.*(Float_t)ngood/(5*fNevents);
 487     AliInfo(Form("Number of set with no misidentified tracks %i (%f %%)", ngood, goodSetPercentage));
 488   }
 489
 490   // free used memory for canvas
 491   delete c1; c1=0;
 492   delete c2; c2=0;
 493   delete c3; c3=0;
 494
 495   // generating output filename only if not previously specified using SetTZeroFile
 496
 497   const Int_t kSize = 70;
 498   char outFileName[kSize];
 499   strncpy(outFileName,"ht010tr120ps",kSize); // global time resolution has to be converted from Int_t to char
 500                                       // in order to have in the output filename this parameter
 501   strncat(outFileName,fHeadersFile,kSize);
 502
 503   if(fT0File.IsNull()) fT0File=outFileName;
 504
 505   TFile* houtfile = new TFile(fT0File,"recreate");
 506   houtfile->cd();
 507   htzerobest->Write(0,TObject::kOverwrite);
 508   hchibest->Write(0,TObject::kOverwrite);
 509   hchibestconflevel->Write(0,TObject::kOverwrite);
 510   houtfile->Close();
 511
 512
 513   if(strstr(option,"tim") || strstr(option,"all")){
 514     gBenchmark->Stop("TOFT0");
 515     AliInfo("AliTOFT0:");
 516     /*
 517     cout << "   took " << gBenchmark->GetCpuTime("TOFT0") << " seconds in order to calculate T0 "
 518          << gBenchmark->GetCpuTime("TOFT0")/fNevents << " seconds per event " << endl ;
 519     */
 520     gBenchmark->Print("TOFT0");
 521   }
 522 }
 523
 524 //__________________________________________________________________
 525 void AliTOFT0::SetTZeroFile(char * file )
 526 {
 527   //
 528   // Set T0 file name
 529   //
 530   printf("Destination file : %s \n", file) ;
 531   fT0File=file;
 532
 533 }
 534
 535 //__________________________________________________________________
 536 void AliTOFT0::Print(Option_t* /*option*/)const
 537 {
 538   //
 539   // Print class content
 540   //
 541   printf("------------------- %s -------------\n", GetName()) ;
 542   if(!fT0File.IsNull())
 543     printf("  Writing T0 Distribution to file  %s \n",(char*) fT0File.Data());
 544
 545 }
 546
 547 //__________________________________________________________________
 548 Bool_t AliTOFT0::operator==( AliTOFT0 const &tzero )const
 549 {
 550   //
 551   // Equal operator
 552   //
 553
 554   if( (fTimeResolution==tzero.fTimeResolution)&&(fLowerMomBound==tzero.fLowerMomBound)&&(fUpperMomBound==tzero.fUpperMomBound))
 555     return kTRUE ;
 556   else
 557     return kFALSE ;
 558 }