1 #include "AliRICHTracker.h"
6 #include "AliRICHHelix.h"
8 #include "AliRICHRecon.h"
10 #include <TParticle.h>
11 #include <TDatabasePDG.h>
13 ClassImp(AliRICHTracker)
14 //__________________________________________________________________________________________________
15 Int_t AliRICHTracker::PropagateBack(AliESD *pESD)
17 //invoked by AliRecontruction for RICH
18 //if ESD doesn't contain tracks, try to reconstruct with particle from STACK
19 //(this case is just to forsee a standalone RICH simulation
21 AliDebug(1,"Start pattern recognition");
22 if(pESD->GetNumberOfTracks()) RecWithESD(pESD);
25 AliDebug(1,"Stop pattern recognition");
27 return 0; // error code: 0=no error;
28 } //pure virtual from AliTracker
29 //__________________________________________________________________________________________________
30 void AliRICHTracker::RecWithESD(AliESD *pESD)
32 //recontruction from ESD
34 Int_t iNtracks=pESD->GetNumberOfTracks();
35 Double_t b=GetFieldMap()->SolenoidField()/10;// magnetic field in Tesla
36 AliDebug(1,Form("Start with %i tracks in %f Tesla field",iNtracks,b));
37 Double_t xb[3],pb[3];//tmp storage for track parameters
38 TVector3 x0(0,0,0); TVector3 p0(0,0,0);//tmp storage for AliRICHHelix
40 AliRICH *pRich=((AliRICH*)gAlice->GetDetector("RICH"));
42 for(Int_t iTrackN=0;iTrackN<iNtracks;iTrackN++){//ESD tracks loop
43 AliESDtrack *pTrack = pESD->GetTrack(iTrackN);// get next reconstructed track
44 // if((pTrack->GetStatus()&AliESDtrack::kTOFout)==0) continue; //ignore tracks not recontructed by TOF
46 pTrack->GetPxPyPz(pb);
47 Int_t status=pTrack->GetStatus()&AliESDtrack::kTOFout;//get running track parameters
48 AliDebug(1,Form("Track %i pmod=%f mass=%f stat=%i",iTrackN,pTrack->GetP(),pTrack->GetMass(),status));
49 x0.SetXYZ(xb[0],xb[1],xb[2]); p0.SetXYZ(xb[0],xb[1],xb[2]);
50 AliRICHHelix helix(x0,p0,pTrack->GetSign(),b);
51 Int_t iChamber=helix.RichIntersect(pRich->P());
52 AliDebug(1,Form("intersection with %i chamber found",iChamber));
53 if(!iChamber) continue;//intersection with no chamber found
55 Double_t distMip=9999; //min distance between clusters and track position on PC
56 Int_t iMipId=0; //index of that min distance cluster
57 for(Int_t iClusN=0;iClusN<pRich->Clusters(iChamber)->GetEntries();iClusN++){//clusters loop for intersected chamber
58 AliRICHcluster *pClus=(AliRICHcluster*)pRich->Clusters(iChamber)->UncheckedAt(iClusN);//get pointer to current cluster
59 Double_t distCurrent=pClus->DistTo(helix.PosPc());//ditance between current cluster and helix intersection with PC
60 if(distCurrent<distMip){distMip=distCurrent;iMipId=iClusN;}//find cluster nearest to the track
62 AliDebug(1,Form("Ploc (%f,%f,%f) dist= %f",helix.Ploc().Mag(),helix.Ploc().Theta()*TMath::RadToDeg(),
63 helix.Ploc().Phi()*TMath::RadToDeg(),pClus->DistTo(helix.PosPc())));
64 }////clusters loop for intersected chamber
66 AliDebug(1,Form("Min distance cluster: %i dist is %f",iMipId,distMip));
68 AliRICHRecon recon(&helix,pRich->Clusters(iChamber),iMipId);
69 Double_t thetaCerenkov=recon.ThetaCerenkov(); //search for mean Cerenkov angle for this track
70 AliDebug(1,Form("FINAL Theta Cerenkov=%f",thetaCerenkov));
71 pTrack->SetRICHsignal(thetaCerenkov);
73 // Double_t richPID[5]={0.2,0.2,0.2,0.2,0.2}; //start with equal probs for (e,mu,pi,k,p)
74 // CalcProb(thetaCerenkov,p0.Mag(),richPID);
75 // pTrack->SetRICHpid(richPID);
80 //__________________________________________________________________________________________________
81 void AliRICHTracker::RecWithStack(TNtupleD *hn)
83 // reconstruction for particles from STACK
85 AliRICH *pRich=((AliRICH*)gAlice->GetDetector("RICH"));
87 // pRich->GetLoader()->GetRunLoader()->LoadHeader();
88 pRich->GetLoader()->GetRunLoader()->LoadKinematics();
89 AliStack *pStack = pRich->GetLoader()->GetRunLoader()->Stack();
90 Int_t iNtracks=pStack->GetNtrack();
91 AliDebug(1,Form(" Start reconstruction with %i track(s) from Stack",iNtracks));
95 Double_t b=GetFieldMap()->SolenoidField()/10;// magnetic field in Tesla
96 AliDebug(1,Form("Start with simulated %i tracks in %f Tesla field",iNtracks,b));
97 TVector3 x0(0,0,0); TVector3 p0(0,0,0);//tmp storage for AliRICHHelix
100 if(pRich->GetLoader()->LoadRecPoints()) {AliDebug(1,Form("No clusters found in RICH"));return;}
101 pRich->GetLoader()->TreeR()->GetEntry(0);
103 for(Int_t iTrackN=0;iTrackN<iNtracks;iTrackN++){//ESD tracks loop
104 TParticle *pParticle = pStack->Particle(iTrackN);
105 if(pParticle->GetMother(0)!=-1) continue; //consider only primaries
106 if(pParticle->GetPDG()->Charge()==0) continue; //to avoid photons from stack...
107 hnvec[0]=pParticle->P();
108 hnvec[1]=pParticle->GetPDG()->Charge();
109 hnvec[2]=pParticle->Theta();
110 hnvec[3]=pParticle->Phi();
111 p0.SetMagThetaPhi(pParticle->P(),pParticle->Theta(),pParticle->Phi());
112 x0.SetXYZ(pParticle->Vx(),pParticle->Vy(),pParticle->Vz());
113 AliRICHHelix helix(x0,p0,Int_t(pParticle->GetPDG()->Charge()/3+0.1),b);
114 Int_t iChamber=helix.RichIntersect(pRich->P());
115 AliDebug(1,Form("intersection with %i chamber found",iChamber));
116 if(!iChamber) continue;// no intersection with RICH found
117 hnvec[4]=helix.PosPc().X();
118 hnvec[5]=helix.PosPc().Y();
119 Double_t distMip=9999; //min distance between clusters and track position on PC
120 Double_t mipX=kBad; //min distance between clusters and track position on PC
121 Double_t mipY=kBad; //min distance between clusters and track position on PC
122 Double_t chargeMip=kBad; // charge MIP to find
123 Int_t iMipId=kBad; //index of that min distance cluster
124 for(Int_t iClusN=0;iClusN<pRich->Clusters(iChamber)->GetEntries();iClusN++){//clusters loop for intersected chamber
125 AliRICHcluster *pClus=(AliRICHcluster*)pRich->Clusters(iChamber)->UncheckedAt(iClusN);//get pointer to current cluster
126 Double_t distCurrent=pClus->DistTo(helix.PosPc());//ditance between current cluster and helix intersection with PC
127 if(distCurrent<distMip){distMip=distCurrent;mipX=pClus->X();
129 chargeMip=pClus->Q();iMipId=1000000*iChamber+iClusN;}//find cluster nearest to the track
131 AliDebug(1,Form("Ploc (%f,%f,%f) dist= %f",helix.Ploc().Mag(),helix.Ploc().Theta()*TMath::RadToDeg(),
132 helix.Ploc().Phi()*TMath::RadToDeg(),pClus->DistTo(helix.PosPc())));
133 }////clusters loop for intersected chamber
135 AliDebug(1,Form("Min distance cluster: %i dist is %f",iMipId,distMip));
136 hnvec[6]=mipX;hnvec[7]=mipY;
138 AliRICHRecon recon(&helix,pRich->Clusters(iChamber),iMipId);
139 Double_t thetaCerenkov=recon.ThetaCerenkov(); //search for mean Cerenkov angle for this track
140 hnvec[9]=thetaCerenkov;
141 hnvec[10]=recon.GetHoughPhotons();
142 hnvec[11]=(Double_t)iMipId;
143 if(hn) hn->Fill(hnvec);
144 AliDebug(1,Form("FINAL Theta Cerenkov=%f",thetaCerenkov));
145 // pTrack->SetRICHsignal(thetaCerenkov);
147 // Double_t richPID[5]={0.2,0.2,0.2,0.2,0.2}; //start with equal probs for (e,mu,pi,k,p)
148 // CalcProb(thetaCerenkov,p0.Mag(),richPID);
152 pRich->GetLoader()->UnloadRecPoints();
157 Int_t AliRICHTracker::LoadClusters(TTree *pTree)
159 // Load clusters for RICH
160 AliDebug(1,"Start."); pTree->GetEntry(0); AliDebug(1,"Stop."); return 0;
163 //__________________________________________________________________________________________________
164 void AliRICHTracker::CalcProb(Double_t thetaCer,Double_t pmod, Double_t *richPID)
167 Double_t height[5];Double_t totalHeight=0;
168 Int_t code[5]={kElectron,kMuonPlus,kPiPlus,kKPlus,kProton};
169 TDatabasePDG *db = new TDatabasePDG();
170 for(Int_t iPart=0;iPart<4;iPart++){
171 Double_t mass = db->GetParticle(code[iPart])->Mass();
172 Double_t refIndex=AliRICHParam::IndOfRefC6F14(6.755);
173 Double_t cosThetaTh = TMath::Sqrt(mass*mass+pmod*pmod)/(refIndex*pmod);
174 if(cosThetaTh>=1) {break;}
175 Double_t thetaTh = TMath::ACos(cosThetaTh);
176 Double_t sinThetaThNorm = TMath::Sin(thetaTh)/TMath::Sqrt(1-1/(refIndex*refIndex));
177 Double_t sigmaThetaTh = (0.014*(1/sinThetaThNorm-1) + 0.0043)*1.25;
178 height[iPart] = TMath::Gaus(thetaCer,thetaTh,sigmaThetaTh);
179 totalHeight +=height[iPart];
181 for(Int_t iPart=0;iPart<5;iPart++) richPID[iPart] = height[iPart]/totalHeight;