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18 //-----------------------------------------------------------------
19 // Implementation of the combined PID class
20 // For the Event Summary Data Class
21 // produced by the reconstruction process
22 // and containing information on the particle identification
23 // Origin: Iouri Belikov, CERN, Jouri.Belikov@cern.ch
24 //-----------------------------------------------------------------
32 #include "AliTOFHeader.h"
33 #include "AliESDpid.h"
34 #include "AliESDEvent.h"
35 #include "AliESDtrack.h"
36 #include "AliMCEvent.h"
38 #include <AliDetectorPID.h>
42 Int_t AliESDpid::MakePID(AliESDEvent *event, Bool_t TPConly, Float_t timeZeroTOF) const {
44 // Calculate probabilities for all detectors, except if TPConly==kTRUE
47 // Option TPConly==kTRUE is used during reconstruction,
48 // because ITS tracking uses TPC pid
49 // HMPID and TRD pid are done in detector reconstructors
53 Float_t timeZeroTOF = 0;
55 timeZeroTOF = event->GetT0();
57 Int_t nTrk=event->GetNumberOfTracks();
58 for (Int_t iTrk=0; iTrk<nTrk; iTrk++) {
59 AliESDtrack *track=event->GetTrack(iTrk);
63 MakeTOFPID(track, timeZeroTOF);
64 //MakeHMPIDPID(track);
71 //_________________________________________________________________________
72 Float_t AliESDpid::GetTPCsignalTunedOnData(const AliVTrack *t) const {
73 AliESDtrack *track = (AliESDtrack *) t;
74 Float_t dedx = track->GetTPCsignalTunedOnData();
76 if(dedx > 0) return dedx;
78 dedx = t->GetTPCsignal();
79 track->SetTPCsignalTunedOnData(dedx);
80 if(dedx < 20) return dedx;
82 AliPID::EParticleType type = AliPID::kPion;
84 AliMCEventHandler* eventHandler=dynamic_cast<AliMCEventHandler*>(fEventHandler);
86 AliMCEvent* mcEvent = eventHandler->MCEvent();
89 AliMCParticle *MCpart = (AliMCParticle *) mcEvent->GetTrack(TMath::Abs(t->GetLabel()));
90 TParticle *part = MCpart->Particle();
92 Int_t iS = TMath::Abs(part->GetPdgCode());
94 if(iS==AliPID::ParticleCode(AliPID::kElectron)){
95 type = AliPID::kElectron;
97 else if(iS==AliPID::ParticleCode(AliPID::kMuon)){
100 else if(iS==AliPID::ParticleCode(AliPID::kPion)){
101 type = AliPID::kPion;
103 else if(iS==AliPID::ParticleCode(AliPID::kKaon)){
104 type = AliPID::kKaon;
106 else if(iS==AliPID::ParticleCode(AliPID::kProton)){
107 type = AliPID::kProton;
109 else if(iS==AliPID::ParticleCode(AliPID::kDeuteron)){ // d
110 type = AliPID::kDeuteron;
112 else if(iS==AliPID::ParticleCode(AliPID::kTriton)){ // t
113 type = AliPID::kTriton;
115 else if(iS==AliPID::ParticleCode(AliPID::kHe3)){ // 3He
118 else if(iS==AliPID::ParticleCode(AliPID::kAlpha)){ // 4He
119 type = AliPID::kAlpha;
125 //TODO maybe introduce different dEdxSources?
126 Double_t bethe = fTPCResponse.GetExpectedSignal(track, type, AliTPCPIDResponse::kdEdxDefault, this->UseTPCEtaCorrection(),
127 this->UseTPCMultiplicityCorrection());
128 Double_t sigma = fTPCResponse.GetExpectedSigma(track, type, AliTPCPIDResponse::kdEdxDefault, this->UseTPCEtaCorrection(),
129 this->UseTPCMultiplicityCorrection());
130 dedx = gRandom->Gaus(bethe,sigma);
131 // if(iS == AliPID::ParticleCode(AliPID::kHe3) || iS == AliPID::ParticleCode(AliPID::kAlpha)) dedx *= 5;
136 track->SetTPCsignalTunedOnData(dedx);
139 //_________________________________________________________________________
140 Float_t AliESDpid::GetTOFsignalTunedOnData(const AliVTrack *t) const {
141 AliESDtrack *track = (AliESDtrack *) t;
142 Double_t tofSignal = track->GetTOFsignalTunedOnData();
144 if(tofSignal < 99999) return (Float_t)tofSignal; // it has been already set
146 tofSignal = t->GetTOFsignal() + fTOFResponse.GetTailRandomValue();
147 track->SetTOFsignalTunedOnData(tofSignal);
148 return (Float_t)tofSignal;
150 //_________________________________________________________________________
151 void AliESDpid::MakeTPCPID(AliESDtrack *track) const
154 // TPC pid using bethe-bloch and gaussian response
156 if ((track->GetStatus()&AliESDtrack::kTPCin )==0)
157 if ((track->GetStatus()&AliESDtrack::kTPCout)==0) return;
159 Double_t mom = track->GetP();
160 const AliExternalTrackParam *in=track->GetInnerParam();
161 if (in) mom = in->GetP();
163 Double_t p[AliPID::kSPECIES];
164 Double_t dedx=track->GetTPCsignal();
165 Bool_t mismatch=kTRUE, heavy=kTRUE;
167 for (Int_t j=0; j<AliPID::kSPECIES; j++) {
168 AliPID::EParticleType type=AliPID::EParticleType(j);
169 Double_t bethe=fTPCResponse.GetExpectedSignal(mom,type);
170 Double_t sigma=fTPCResponse.GetExpectedSigma(mom,track->GetTPCsignalN(),type);
171 if (TMath::Abs(dedx-bethe) > fRange*sigma) {
172 p[j]=TMath::Exp(-0.5*fRange*fRange)/sigma;
174 p[j]=TMath::Exp(-0.5*(dedx-bethe)*(dedx-bethe)/(sigma*sigma))/sigma;
178 // Check for particles heavier than (AliPID::kSPECIES - 1)
179 if (dedx < (bethe + fRange*sigma)) heavy=kFALSE;
184 for (Int_t j=0; j<AliPID::kSPECIES; j++) p[j]=1./AliPID::kSPECIES;
188 if (heavy) track->ResetStatus(AliESDtrack::kTPCpid);
191 //_________________________________________________________________________
192 void AliESDpid::MakeITSPID(AliESDtrack *track) const
196 // Two options, depending on fITSPIDmethod:
197 // 1) Truncated mean method
198 // 2) Likelihood, using charges measured in all 4 layers and
199 // Landau+gaus response functions
202 if ((track->GetStatus()&AliESDtrack::kITSin)==0 &&
203 (track->GetStatus()&AliESDtrack::kITSout)==0) return;
205 Double_t mom=track->GetP();
206 if (fITSPIDmethod == kITSTruncMean) {
207 Double_t dedx=track->GetITSsignal();
210 ULong_t trStatus=track->GetStatus();
211 if(trStatus&AliESDtrack::kTPCin) isSA=kFALSE;
212 UChar_t clumap=track->GetITSClusterMap();
213 Int_t nPointsForPid=0;
214 for(Int_t i=2; i<6; i++){
215 if(clumap&(1<<i)) ++nPointsForPid;
218 if(nPointsForPid<3) { // track not to be used for combined PID purposes
219 track->ResetStatus(AliESDtrack::kITSpid);
225 Bool_t mismatch=kTRUE, heavy=kTRUE;
226 for (Int_t j=0; j<AliPID::kSPECIES; j++) {
227 Double_t mass=AliPID::ParticleMass(j);//GeV/c^2
228 Double_t bethe=fITSResponse.Bethe(momITS,mass);
229 Double_t sigma=fITSResponse.GetResolution(bethe,nPointsForPid,isSA);
230 if (TMath::Abs(dedx-bethe) > fRange*sigma) {
231 p[j]=TMath::Exp(-0.5*fRange*fRange)/sigma;
233 p[j]=TMath::Exp(-0.5*(dedx-bethe)*(dedx-bethe)/(sigma*sigma))/sigma;
237 // Check for particles heavier than (AliPID::kSPECIES - 1)
238 if (dedx < (bethe + fRange*sigma)) heavy=kFALSE;
243 for (Int_t j=0; j<AliPID::kSPECIES; j++) p[j]=1./AliPID::kSPECIES;
247 if (heavy) track->ResetStatus(AliESDtrack::kITSpid);
249 else { // Likelihood method
250 Double_t condprobfun[AliPID::kSPECIES];
252 track->GetITSdEdxSamples(qclu);
253 fITSResponse.GetITSProbabilities(mom,qclu,condprobfun);
254 track->SetITSpid(condprobfun);
258 //_________________________________________________________________________
259 void AliESDpid::MakeTOFPID(AliESDtrack *track, Float_t /*timeZeroTOF*/) const
262 // TOF PID using gaussian response
265 if ((track->GetStatus()&AliESDtrack::kTOFout)==0) return;
266 if ((track->GetStatus()&AliESDtrack::kTIME)==0) return;
267 if ((track->GetStatus()&AliESDtrack::kITSin)==0) return;
269 Int_t ibin = fTOFResponse.GetMomBin(track->GetP());
270 Float_t timezero = fTOFResponse.GetT0bin(ibin);
272 Double_t time[AliPID::kSPECIES];
273 track->GetIntegratedTimes(time);
275 Double_t sigma[AliPID::kSPECIES];
276 for (Int_t iPart = 0; iPart < AliPID::kSPECIES; iPart++) {
277 sigma[iPart] = fTOFResponse.GetExpectedSigma(track->GetP(),time[iPart],AliPID::ParticleMass(iPart));
280 AliDebugGeneral("AliESDpid::MakeTOFPID",2,
281 Form("Expected TOF signals [ps]: %f %f %f %f %f",
282 time[AliPID::kElectron],
286 time[AliPID::kProton]));
288 AliDebugGeneral("AliESDpid::MakeTOFPID",2,
289 Form("Expected TOF std deviations [ps]: %f %f %f %f %f",
290 sigma[AliPID::kElectron],
291 sigma[AliPID::kMuon],
292 sigma[AliPID::kPion],
293 sigma[AliPID::kKaon],
294 sigma[AliPID::kProton]
297 Double_t tof = track->GetTOFsignal() - timezero;
299 Double_t p[AliPID::kSPECIES];
300 // Bool_t mismatch = kTRUE;
301 Bool_t heavy = kTRUE;
302 for (Int_t j=0; j<AliPID::kSPECIES; j++) {
303 Double_t sig = sigma[j];
304 if (TMath::Abs(tof-time[j]) > (fRange+2)*sig) {
305 p[j] = TMath::Exp(-0.5*(fRange+2)*(fRange+2))/sig;
307 p[j] = TMath::Exp(-0.5*(tof-time[j])*(tof-time[j])/(sig*sig))/sig;
309 // Check the mismatching
311 // Double_t mass = AliPID::ParticleMass(j);
312 // Double_t pm = fTOFResponse.GetMismatchProbability(track->GetP(),mass);
313 // if (p[j]>pm) mismatch = kFALSE;
315 // Check for particles heavier than (AliPID::kSPECIES - 1)
316 if (tof < (time[j] + fRange*sig)) heavy=kFALSE;
322 for (Int_t j=0; j<AliPID::kSPECIES; j++) p[j]=1./AliPID::kSPECIES;
327 if (heavy) track->ResetStatus(AliESDtrack::kTOFpid);
329 // kTOFmismatch flas is not set because deprecated from 18/02/2013
330 // if (!CheckTOFMatching(track)) track->SetStatus(AliESDtrack::kTOFmismatch);
331 // else track->ResetStatus(AliESDtrack::kTOFmismatch);
333 //_________________________________________________________________________
334 void AliESDpid::MakeTRDPID(AliESDtrack *track) const
337 // Method to recalculate the TRD PID probabilities
339 Double_t prob[AliPID::kSPECIES];
340 GetComputeTRDProbability(track, AliPID::kSPECIES, prob);
341 track->SetTRDpid(prob);
343 //_________________________________________________________________________
344 void AliESDpid::CombinePID(AliESDtrack *track) const
347 // Combine the information of various detectors
348 // to determine the Particle Identification
350 Int_t ns=AliPID::kSPECIES;
351 Double_t p[10]={1.,1.,1.,1.,1.,1.,1.,1.,1.,1.};
353 if (track->IsOn(AliESDtrack::kITSpid)) {
356 for (Int_t j=0; j<ns; j++) p[j]*=d[j];
359 if (track->IsOn(AliESDtrack::kTPCpid)) {
362 for (Int_t j=0; j<ns; j++) p[j]*=d[j];
365 if (track->IsOn(AliESDtrack::kTRDpid)) {
368 for (Int_t j=0; j<ns; j++) p[j]*=d[j];
371 if (track->IsOn(AliESDtrack::kTOFpid)) {
374 for (Int_t j=0; j<ns; j++) p[j]*=d[j];
377 if (track->IsOn(AliESDtrack::kHMPIDpid)) {
379 track->GetHMPIDpid(d);
380 for (Int_t j=0; j<ns; j++) p[j]*=d[j];
385 //_________________________________________________________________________
386 Bool_t AliESDpid::CheckTOFMatching(AliESDtrack *track) const{
388 // Check pid matching of TOF with TPC as reference
390 Bool_t status = kFALSE;
392 Double_t exptimes[5];
393 track->GetIntegratedTimes(exptimes);
395 Float_t p = track->P();
397 Float_t dedx = track->GetTPCsignal();
398 Float_t time = track->GetTOFsignal() - fTOFResponse.GetStartTime(p);
401 track->GetInnerPxPyPz(ptpc);
402 Float_t momtpc=TMath::Sqrt(ptpc[0]*ptpc[0] + ptpc[1]*ptpc[1] + ptpc[2]*ptpc[2]);
404 for(Int_t i=0;i < 5;i++){
405 AliPID::EParticleType type=AliPID::EParticleType(i);
407 Float_t resolutionTOF = fTOFResponse.GetExpectedSigma(p, exptimes[i], AliPID::ParticleMass(i));
408 if(TMath::Abs(exptimes[i] - time) < fRange * resolutionTOF){
409 Float_t dedxExp = fTPCResponse.GetExpectedSignal(momtpc,type);
410 Float_t resolutionTPC = fTPCResponse.GetExpectedSigma(momtpc,track->GetTPCsignalN(),type);
412 if(TMath::Abs(dedx - dedxExp) < fRangeTOFMismatch * resolutionTPC){
419 Float_t resolutionTOFpr = fTOFResponse.GetExpectedSigma(p, exptimes[4], AliPID::ParticleMass(4));
420 if(!status && (exptimes[4] + fRange*resolutionTOFpr < time)) status = kTRUE;
426 //_________________________________________________________________________
427 Float_t AliESDpid::GetSignalDeltaTOFold(const AliVParticle *track, AliPID::EParticleType type, Bool_t ratio/*=kFALSE*/) const
430 // TOF signal - expected
432 AliVTrack *vtrack=(AliVTrack*)track;
434 const Double_t expTime = fTOFResponse.GetExpectedSignal(vtrack,type);
435 Double_t tofTime = 99999;
436 if (fTuneMConData && ((fTuneMConDataMask & kDetTOF) == kDetTOF) ) tofTime = (Double_t)this->GetTOFsignalTunedOnData((AliVTrack*)vtrack);
437 else tofTime=vtrack->GetTOFsignal();
438 tofTime = tofTime - fTOFResponse.GetStartTime(vtrack->P());
439 Double_t delta=-9999.;
441 if (!ratio) delta=tofTime-expTime;
442 else if (expTime>1.e-20) delta=tofTime/expTime;
447 //_________________________________________________________________________
448 Float_t AliESDpid::GetNumberOfSigmasTOFold(const AliVParticle *track, AliPID::EParticleType type) const
451 // Number of sigma implementation for the TOF
454 AliVTrack *vtrack=(AliVTrack*)track;
455 Double_t tofTime = 99999;
456 if (fTuneMConData && ((fTuneMConDataMask & kDetTOF) == kDetTOF) ) tofTime = (Double_t)this->GetTOFsignalTunedOnData((AliVTrack*)vtrack);
457 else tofTime=vtrack->GetTOFsignal();
459 Double_t expTime = fTOFResponse.GetExpectedSignal(vtrack,type);
460 return (tofTime - fTOFResponse.GetStartTime(vtrack->P()) - expTime)/fTOFResponse.GetExpectedSigma(vtrack->P(),expTime,AliPID::ParticleMassZ(type));