First prototype of TOF reconstruction
[u/mrichter/AliRoot.git] / TOF / AliTOFT0.cxx
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d599d913 1/**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
3 * *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
6 * *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
15
16//_________________________________________________________________________
17// This is a TTask that made the calculation of the Time zero using TOF.
18// Description: The algorithm used to calculate the time zero of interaction
19// using TOF detector is the following.
20// We select in the MonteCarlo some primary particles - or tracks in the following -
21// that strike the TOF detector (the larger part are pions, kaons or protons).
22// We choose a set of 10 selected tracks, for each track You have the length
23// of the track when the TOF is reached (a standard TOF hit does not contain this
24// additional information, this is the reason why we implemented a new time zero
25// dedicated TOF hit class AliTOFhitT0; in order to store this type of hit You
26// have to use the AliTOFv4T0 as TOF class in Your Config.C. In AliTOFv4T0 the
27// StepManager was modified in order to fill the TOF hit branch with this type
28// of hits; in fact the AliTOF::AddT0Hit is called rather that the usual AliTOF::AddHit),
29// the momentum at generation (from TreeK) and the time of flight
30// given by the TOF detector.
31// (Observe that the ctor of the AliTOF class, when the AliTOFv4T0 class is used, is called
32// with the "tzero" option: it is in order create the fHits TClonesArray filled with
33// AliTOFhitT0 objects, rather than with normal AliTOFhit)
34// Then Momentum and time of flight for each track are smeared according to
35// known experimental resolution (all sources of error have been token into account).
36// Let consider now only one set of 10 tracks (the algorithm is the same for all sets).
37// Assuming the (mass) hypothesis that each track can be AUT a pion, AUT a kaon, AUT a proton,
38// we consider all the 3 at 10 possible cases.
39// For each track in each (mass) configuration
40// (a configuration can be e.g. pion/pion/kaon/proton/pion/proton/kaon/kaon/pion/pion)
41// we calculate the time zero (we know in fact the velocity of the track after
42// the assumption about its mass, the time of flight given by the TOF, and the
43// corresponding path travelled till the TOF detector). Then for each mass configuration we have
44// 10 time zero and we can calculate the ChiSquare for the current configuration using the
45// weighted mean over all 10 time zero.
46// We call the best assignment the mass configuration that gives the minimum value of the ChiSquare.
47// We plot the weighted mean over all 10 time zero for the best assignment,
48// the ChiSquare for the best assignment and the corresponding confidence level.
49// The strong assumption is the MC selection of primary particles. It will be introduced
50// in the future also some more realistic simulation about this point.
51// Use case:
52// root [0] AliTOFT0 * tzero = new AliTOFT0("galice.root")
53// Warning in <TDatabasePDG::TDatabasePDG>: object already instantiated
54// root [1] tzero->ExecuteTask()
55// root [2] tzero->ExecuteTask("tim")
56// // available parameters:
57// tim - print benchmarking information
58// all - print usefull informations about the number of misidentified tracks
59// and a comparison about the true configuration (known from MC) and the best
60// assignment
61//-- Author: F. Pierella
62//////////////////////////////////////////////////////////////////////////////
63
64#include "AliTOFT0.h"
65#include "AliTOFhitT0.h"
66#include "AliTOF.h"
67#include "AliTOFv4T0.h"
68#include "AliRun.h"
69#include "AliDetector.h"
70#include "AliMC.h"
71
72#include "TH1.h"
73#include "TFile.h"
74#include "TTask.h"
75#include "TTree.h"
76#include "TSystem.h"
77#include "TCanvas.h"
78#include "TFrame.h"
79#include "TROOT.h"
80#include "TFolder.h"
81#include "TBenchmark.h"
82#include "TParticle.h"
83#include "TClonesArray.h"
84#include <stdlib.h>
85#include <iostream.h>
86#include <fstream.h>
87#include <iomanip.h>
88
89ClassImp(AliTOFT0)
90
91//____________________________________________________________________________
92 AliTOFT0::AliTOFT0():TTask("AliTOFT0","")
93{
94 // ctor
95 fNevents = 0 ;
96 fHits = 0 ;
97
98}
99
100//____________________________________________________________________________
101 AliTOFT0::AliTOFT0(char* headerFile, Int_t nEvents):TTask("AliTOFT0","")
102{
103 fNevents=nEvents ; // Number of events for which calculate the T0,
104 // default 0: it means all evens in current file
105 fLowerMomBound=1.5; // [GeV/c] default value
106 fUpperMomBound=2. ; // [GeV/c] default value
107 fTimeResolution = 1.2e-10; // 120 ps by default
108 fHeadersFile = headerFile ;
109 fHits = 0 ;
110
111 TFile * file = (TFile*) gROOT->GetFile(fHeadersFile.Data() ) ;
112
113 //File was not opened yet
114 if(file == 0){
115 if(fHeadersFile.Contains("rfio"))
116 file = TFile::Open(fHeadersFile,"update") ;
117 else
118 file = new TFile(fHeadersFile.Data(),"update") ;
119 gAlice = (AliRun *) file->Get("gAlice") ;
120 }
121
122 // add Task to //root/Tasks folder
123 TTask * roottasks = (TTask*)gROOT->GetRootFolder()->FindObject("Tasks") ;
124 roottasks->Add(this) ;
125}
126
127//____________________________________________________________________________
128 AliTOFT0::~AliTOFT0()
129{
130 // dtor
131}
132
133//____________________________________________________________________________
134void AliTOFT0::Exec(Option_t *option)
135{
136 //
137 // calculate T0 distribution for all events using chisquare
138 //
139 Int_t ngood=0;
140 Int_t nmisidentified=0;
141 Int_t nmisidentified0=0;
142 Int_t nmisidentified1=0;
143 Int_t nmisidentified2=0;
144 Int_t nmisidentified3=0;
145 Int_t nmisidentified4=0;
146 Int_t nmisidentified5=0;
147 Int_t nmisidentified6=0;
148 Int_t nmisidentified7=0;
149 Int_t nmisidentified8=0;
150 Int_t nmisidentified9=0;
151 Int_t ipartold = -1;
152 Int_t ipart;
153 Int_t selected=0;
154 Int_t istop=0;
155 Float_t timeresolutioninns=fTimeResolution*(1.e+9); // convert in [ns]
156 const Int_t kUPDATE = 5; // for visual option
157 Int_t itimes=0;
158 TCanvas* c1=0;
159 TCanvas* c2=0;
160 TCanvas* c3=0;
161
162 if(strstr(option,"visual")){
163 // Create a new canvas.
164 //c1 = new TCanvas("c1","Dynamic Visual Filling of time zero histo",10,10,500,500);
165 c1 = new TCanvas("c1","Dynamic Visual Filling of time zero histo",10,10,370,370);
166 c1->SetFillColor(35);
167 c1->GetFrame()->SetFillColor(21);
168 c1->GetFrame()->SetBorderSize(6);
169 c1->GetFrame()->SetBorderMode(-1);
170
171 //c2 = new TCanvas("c2","Dynamic Visual Filling of chisquare histo",550,10,500,500);
172 c2 = new TCanvas("c2","Dynamic Visual Filling of chisquare histo",380,10,370,370);
173 c2->SetFillColor(35);
174 c2->GetFrame()->SetFillColor(21);
175 c2->GetFrame()->SetBorderSize(6);
176 c2->GetFrame()->SetBorderMode(-1);
177
178 //c3 = new TCanvas("c3","Dynamic Visual Filling of confidence level histo",280,550,500,500);
179 c3 = new TCanvas("c3","Dynamic Visual Filling of confidence level histo",760,10,370,370);
180 c3->SetFillColor(35);
181 c3->GetFrame()->SetFillColor(21);
182 c3->GetFrame()->SetBorderSize(6);
183 c3->GetFrame()->SetBorderMode(-1);
184 }
185
186 if(strstr(option,"tim") || strstr(option,"all"))
187 gBenchmark->Start("TOFT0");
188
189 TH1F *htzerobest= new TH1F("htzerobest","T0 for best assignment",200,-1.,1.);
190 TH1F* hchibest = new TH1F("hchibest","ChiSquare Min Distribution",80,0.,40.);
191 TH1F* hchibestconflevel = new TH1F("hchibestconflevel","ChiSquare Min Confidence Level",10,0.,1.);
192
193 // setting histo colors
194 if(strstr(option,"visual")){
195 htzerobest->SetFillColor(48);
196 hchibest->SetFillColor(50);
197 hchibestconflevel->SetFillColor(52);
198 }
199
200 Int_t assparticle[10]={3,3,3,3,3,3,3,3,3,3};
201 Int_t truparticle[10]={3,3,3,3,3,3,3,3,3,3};
202 Float_t t0best=999.;
203 Float_t timeofflight[10]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
204 Float_t momentum[10]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
205 Float_t timezero[10];
206 Float_t weightedtimezero[10];
207 Float_t beta[10]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
208 Float_t sqMomError[10]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
209 Float_t sqTrackError[10]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
210 Float_t massarray[3]={0.13957,0.493677,0.9382723};
211 Float_t dummychisquare=0.;
212 Float_t chisquare=999.;
213 Float_t tracktoflen[10]={0.,0.,0.,0.,0.,0.,0.,0.,0.,0.};
214
215 AliTOF *TOF = (AliTOF *) gAlice->GetDetector ("TOF");
216
217 if (!TOF) {
218 Error("AliTOFT0","TOF not found");
219 return;
220 }
221
222 if(strstr(option,"all")){
223 cout << "Selecting primary tracks with momentum between " << fLowerMomBound << " GeV/c and " << fUpperMomBound << " GeV/c" << endl;
224 cout << "Memorandum: 0 means PION | 1 means KAON | 2 means PROTON" << endl;
225 }
226
227 if (fNevents == 0) fNevents = (Int_t) gAlice->TreeE()->GetEntries();
228
229 for (Int_t ievent = 0; ievent < fNevents; ievent++) {
230 gAlice->GetEvent(ievent);
231 TTree *TH = gAlice->TreeH ();
232 if (!TH)
233 return;
234 TParticle* particle;
235 AliTOFhitT0* tofHit;
236 TClonesArray* TOFhits = TOF->Hits();
237
238 Int_t lasttrack=-1;
239 Int_t nset=0;
240 // Start loop on primary tracks in the hits containers
241
242 Int_t ntracks = static_cast<Int_t>(TH->GetEntries());
243 for (Int_t track = 0; track < ntracks; track++)
244 {
245 if(nset>=5) break; // check on the number of set analyzed
246
247 gAlice->ResetHits();
248 TH->GetEvent(track);
249 particle = gAlice->Particle(track);
250 Int_t nhits = TOFhits->GetEntriesFast();
251
252 for (Int_t hit = 0; hit < nhits; hit++)
253 {
254 tofHit = (AliTOFhitT0 *) TOFhits->UncheckedAt(hit);
255 ipart = tofHit->GetTrack();
256 // check to discard the case when the same particle is selected more than one
257 // time
258
259 if (ipart != ipartold){
260
261 particle = (TParticle*)gAlice->Particle(ipart);
262
263 Float_t idealtime=tofHit->GetTof();
264 // Float_t time=idealtime;
265 Float_t time = gRandom->Gaus(idealtime, fTimeResolution);
266 Float_t toflen=tofHit->GetLen();
267 toflen=toflen/100.; // toflen given in m
268 Int_t pdg = particle->GetPdgCode();
269 Int_t abspdg =TMath::Abs(pdg);
270 Float_t idealmom = particle->P();
271 Float_t momres=idealmom*0.025; // 2.5% res token into account for all momenta
272 Float_t mom =gRandom->Gaus(idealmom,momres);
273
274 Bool_t isgoodpart=(abspdg==211 || abspdg==2212 || abspdg==321);
275
276 time*=1.E+9; // tof given in nanoseconds
277 if (particle->GetFirstMother() < 0 && isgoodpart && mom<=fUpperMomBound && mom>=fLowerMomBound){
278 selected+=1;
279 istop=selected;
280 if(istop>10) break;
281 Int_t index=selected-1;
282 timeofflight[index]=time;
283 tracktoflen[index]=toflen;
284 momentum[index]=mom;
285 // cout << timeofflight[index] << " " << tracktoflen[index] << " " << momentum[index] << endl;
286 switch (abspdg) {
287 case 211:
288 truparticle[index]=0;
289 break ;
290 case 321:
291 truparticle[index]=1;
292 break ;
293 case 2212:
294 truparticle[index]=2;
295 break ;
296 }
297
298 }
299 ipartold = ipart;
300
301 if(istop==10){ // start analysis on current set
302 nset+=1;
303 lasttrack=track;
304 istop=0;
305 selected=0;
306 //cout << "starting t0 calculation for current set" << endl;
307 for (Int_t i1=0; i1<3;i1++) {
308 for (Int_t i2=0; i2<3;i2++) {
309 for (Int_t i3=0; i3<3;i3++) {
310 for (Int_t i4=0; i4<3;i4++) {
311 for (Int_t i5=0; i5<3;i5++) {
312 for (Int_t i6=0; i6<3;i6++) {
313 for (Int_t i7=0; i7<3;i7++) {
314 for (Int_t i8=0; i8<3;i8++) {
315 for (Int_t i9=0; i9<3;i9++) {
316 for (Int_t i10=0; i10<3;i10++) {
317
318 beta[0]=momentum[0]/sqrt(massarray[i1]*massarray[i1]+momentum[0]*momentum[0]);
319 beta[1]=momentum[1]/sqrt(massarray[i2]*massarray[i2]+momentum[1]*momentum[1]);
320 beta[2]=momentum[2]/sqrt(massarray[i3]*massarray[i3]+momentum[2]*momentum[2]);
321 beta[3]=momentum[3]/sqrt(massarray[i4]*massarray[i4]+momentum[3]*momentum[3]);
322 beta[4]=momentum[4]/sqrt(massarray[i5]*massarray[i5]+momentum[4]*momentum[4]);
323 beta[5]=momentum[5]/sqrt(massarray[i6]*massarray[i6]+momentum[5]*momentum[5]);
324 beta[6]=momentum[6]/sqrt(massarray[i7]*massarray[i7]+momentum[6]*momentum[6]);
325 beta[7]=momentum[7]/sqrt(massarray[i8]*massarray[i8]+momentum[7]*momentum[7]);
326 beta[8]=momentum[8]/sqrt(massarray[i9]*massarray[i9]+momentum[8]*momentum[8]);
327 beta[9]=momentum[9]/sqrt(massarray[i10]*massarray[i10]+momentum[9]*momentum[9]);
328
329
330 Float_t meantzero=0.;
331 Float_t sumAllweights=0.;
332 for (Int_t itz=0; itz<10;itz++) {
333 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
334 sqTrackError[itz]=(timeresolutioninns*timeresolutioninns+sqMomError[itz]); // total error for the current track
335 sumAllweights+=1./sqTrackError[itz];
336 // redefining beta, it is useful in order to calculate t zero
337 beta[itz]*=0.299792;
338 timezero[itz]=(tracktoflen[itz]/beta[itz])-timeofflight[itz];
339 weightedtimezero[itz]=((tracktoflen[itz]/beta[itz])-timeofflight[itz])/sqTrackError[itz];// weighted time zero for current track
340 meantzero+=weightedtimezero[itz];
341 } // end loop for (Int_t itz=0; itz<10;itz++)
342 meantzero=meantzero/sumAllweights; // it is given in [ns]
343
344 dummychisquare=0.;
345 // calculate the chisquare for the current assignment
346 for (Int_t icsq=0; icsq<10;icsq++) {
347 dummychisquare+=(timezero[icsq]-meantzero)*(timezero[icsq]-meantzero)/sqTrackError[icsq];
348 } // end loop for (Int_t icsq=0; icsq<10;icsq++)
349
350 if(dummychisquare<=chisquare){
351 assparticle[0]=i1;
352 assparticle[1]=i2;
353 assparticle[2]=i3;
354 assparticle[3]=i4;
355 assparticle[4]=i5;
356 assparticle[5]=i6;
357 assparticle[6]=i7;
358 assparticle[7]=i8;
359 assparticle[8]=i9;
360 assparticle[9]=i10;
361 chisquare=dummychisquare;
362 t0best=meantzero;
363 } // close if(dummychisquare<=chisquare)
364
365 } // end loop on i10
366 } // end loop on i9
367 } // end loop on i8
368 } // end loop on i7
369 } // end loop on i6
370 } // end loop on i5
371 } // end loop on i4
372 } // end loop on i3
373 } // end loop on i2
374 } // end loop on i1
375
376 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;
377 if(truparticle[0]!=assparticle[0]) nmisidentified0+=1;
378 if(truparticle[1]!=assparticle[1]) nmisidentified1+=1;
379 if(truparticle[2]!=assparticle[2]) nmisidentified2+=1;
380 if(truparticle[3]!=assparticle[3]) nmisidentified3+=1;
381 if(truparticle[4]!=assparticle[4]) nmisidentified4+=1;
382 if(truparticle[5]!=assparticle[5]) nmisidentified5+=1;
383 if(truparticle[6]!=assparticle[6]) nmisidentified6+=1;
384 if(truparticle[7]!=assparticle[7]) nmisidentified7+=1;
385 if(truparticle[8]!=assparticle[8]) nmisidentified8+=1;
386 if(truparticle[9]!=assparticle[9]) nmisidentified9+=1;
387 // filling histos
388 htzerobest->Fill(t0best);
389 hchibest->Fill(chisquare);
390 Double_t dblechisquare=(Double_t)chisquare;
391 Float_t confLevel=(Float_t)TMath::Prob(dblechisquare,9); // ndf 10-1=9
392 hchibestconflevel->Fill(confLevel);
393 itimes++;
394 if(strstr(option,"all")){
395 cout << "True Assignment " << truparticle[0] << truparticle[1] << truparticle[2] << truparticle[3] << truparticle[4] << truparticle[5] << truparticle[6] << truparticle[7] << truparticle[8] << truparticle[9] <<endl;
396 cout << "Best Assignment " << assparticle[0] << assparticle[1] << assparticle[2] << assparticle[3] << assparticle[4] << assparticle[5] << assparticle[6] << assparticle[7] << assparticle[8] << assparticle[9] << endl;
397 cout << "Minimum ChiSquare for current set " << chisquare << endl;
398 cout << "Confidence Level (Minimum ChiSquare) " << confLevel << endl;
399 }
400 if (strstr(option,"visual") && itimes && (itimes%kUPDATE) == 0) {
401 if (itimes == kUPDATE){
402 c1->cd();
403 htzerobest->Draw();
404 c2->cd();
405 hchibest->Draw();
406 c3->cd();
407 hchibestconflevel->Draw();
408 }
409 c1->Modified();
410 c1->Update();
411 c2->Modified();
412 c2->Update();
413 c3->Modified();
414 c3->Update();
415 if (gSystem->ProcessEvents())
416 break;
417 }
418 chisquare=999.;
419 t0best=999.;
420
421 } // end for the current set. close if(istop==5)
422 } // end condition on ipartold
423 } // end loop on hits for the current track
424 if(istop>=10) break;
425 } // end loop on ntracks
426 } //event loop
427
428 if(strstr(option,"all")){
429 nmisidentified=(nmisidentified0+nmisidentified1+nmisidentified2+nmisidentified3+nmisidentified4+nmisidentified5+nmisidentified6+nmisidentified7+nmisidentified8+nmisidentified9);
430 cout << "total number of tracks token into account " << 10*5*fNevents << endl;
431 Float_t badPercentage=100.*(Float_t)nmisidentified/(10*5*fNevents);
432 cout << "total misidentified " << nmisidentified << "("<< badPercentage << "%)" <<endl;
433 cout << "Total Number of set token into account " << 5*fNevents << endl;
434 Float_t goodSetPercentage=100.*(Float_t)ngood/(5*fNevents);
435 cout << "Number of set with no misidentified tracks " << ngood << "("<< goodSetPercentage << "%)" <<endl;
436 }
437
438 // free used memory for canvas
439 delete c1; c1=0;
440 delete c2; c2=0;
441 delete c3; c3=0;
442
443 // generating output filename only if not previously specified using SetTZeroFile
444 char outFileName[70];
445 strcpy(outFileName,"ht010tr120ps"); // global time resolution has to be converted from Int_t to char
446 // in order to have in the output filename this parameter
447 strcat(outFileName,fHeadersFile);
448
449 if(fT0File.IsNull()) fT0File=outFileName;
450
451 TFile* houtfile = new TFile(fT0File,"recreate");
452 houtfile->cd();
453 htzerobest->Write(0,TObject::kOverwrite);
454 hchibest->Write(0,TObject::kOverwrite);
455 hchibestconflevel->Write(0,TObject::kOverwrite);
456 houtfile->Close();
457
458
459 if(strstr(option,"tim") || strstr(option,"all")){
460 gBenchmark->Stop("TOFT0");
461 cout << "AliTOFT0:" << endl ;
462 cout << " took " << gBenchmark->GetCpuTime("TOFT0") << " seconds in order to calculate T0 "
463 << gBenchmark->GetCpuTime("TOFT0")/fNevents << " seconds per event " << endl ;
464 cout << endl ;
465 }
466}
467
468//__________________________________________________________________
469void AliTOFT0::SetTZeroFile(char * file ){
470 cout << "Destination file : " << file << endl ;
471 fT0File=file;
472}
473//__________________________________________________________________
474void AliTOFT0::Print(Option_t* option)const
475{
476 cout << "------------------- "<< GetName() << " -------------" << endl ;
477 if(!fT0File.IsNull())
478 cout << " Writing T0 Distribution to file " << (char*) fT0File.Data() << endl ;
479}
480
481//__________________________________________________________________
482Bool_t AliTOFT0::operator==( AliTOFT0 const &tzero )const
483{
484 // Equal operator.
485 //
486
487 if( (fTimeResolution==tzero.fTimeResolution)&&(fLowerMomBound==tzero.fLowerMomBound)&&(fUpperMomBound==tzero.fUpperMomBound))
488 return kTRUE ;
489 else
490 return kFALSE ;
491}
492