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75c74fab | 1 | /************************************************************************** |
2 | * Copyright(c) 2007-2009, 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 | /* $Id$ */ | |
17 | ||
18 | /////////////////////////////////////////////////////////////////// | |
19 | // // | |
20 | // Implementation of the base class for dEdx analysis // | |
21 | // Origin: F.Prino, Torino, prino@to.infn.it // | |
22 | // // | |
23 | /////////////////////////////////////////////////////////////////// | |
24 | ||
25 | #include <TString.h> | |
26 | #include <TFile.h> | |
27 | #include <TParticlePDG.h> | |
28 | #include <TDatabasePDG.h> | |
b34fed4e | 29 | #include "AliStack.h" |
30 | #include "AliLog.h" | |
27199d86 | 31 | #include "AliESDEvent.h" |
32 | #include "AliStack.h" | |
75c74fab | 33 | #include "AliITSdEdxAnalyzer.h" |
34 | #include "AliExternalTrackParam.h" | |
10d100d4 | 35 | //#include "AliITSpidESD.h" |
36 | #include "AliITSPIDResponse.h" | |
75c74fab | 37 | #include "AliPID.h" |
38 | ||
39 | ClassImp(AliITSdEdxAnalyzer) | |
40 | ||
41 | const Int_t AliITSdEdxAnalyzer::fgkPdgCode[kNParticles]={211,321,2212}; | |
42 | const Int_t AliITSdEdxAnalyzer::fgkLayerCode[kNValuesdEdx]={3,4,5,6,0}; | |
43 | ||
44 | //______________________________________________________________________ | |
45 | AliITSdEdxAnalyzer::AliITSdEdxAnalyzer() : | |
46 | TObject(), | |
47 | fNPBins(10), | |
48 | fPMin(0.1), | |
49 | fPMax(1.1), | |
50 | fHistodEdx(0), | |
51 | fHistoDeltadEdx(0), | |
52 | fHistodEdxVsP(0), | |
53 | fThickness(0.03), | |
54 | fDensity(2.33), | |
55 | fBBmodel(0), | |
56 | fMIP(82.), | |
57 | fTPCpidCut(0.5) | |
58 | { | |
59 | // default constructor | |
60 | BookHistos(); | |
61 | } | |
62 | //______________________________________________________________________ | |
63 | AliITSdEdxAnalyzer::AliITSdEdxAnalyzer(const Int_t npbins, const Float_t pmin, const Float_t pmax) : | |
64 | TObject(), | |
65 | fNPBins(npbins), | |
66 | fPMin(pmin), | |
67 | fPMax(pmax), | |
68 | fHistodEdx(0), | |
69 | fHistoDeltadEdx(0), | |
70 | fHistodEdxVsP(0), | |
71 | fThickness(0.03), | |
72 | fDensity(2.33), | |
73 | fBBmodel(0), | |
74 | fMIP(82.), | |
75 | fTPCpidCut(0.5) | |
76 | { | |
77 | // standard constructor | |
78 | BookHistos(); | |
79 | } | |
80 | //______________________________________________________________________ | |
81 | AliITSdEdxAnalyzer::~AliITSdEdxAnalyzer(){ | |
82 | // destructor | |
83 | DeleteHistos(); | |
84 | } | |
85 | //______________________________________________________________________ | |
86 | void AliITSdEdxAnalyzer::SetMomentumBins(const Int_t npbins, const Float_t pmin, const Float_t pmax){ | |
87 | // Kill exisiting histos, set new binning, book new histos | |
88 | DeleteHistos(); | |
89 | fNPBins=npbins; | |
90 | fPMin=pmin; | |
91 | fPMax=pmax; | |
92 | BookHistos(); | |
93 | } | |
94 | //______________________________________________________________________ | |
95 | void AliITSdEdxAnalyzer::DeleteHistos(){ | |
b34fed4e | 96 | // deletes the hitograms |
75c74fab | 97 | if(fHistodEdx){ |
98 | for(Int_t i=0; i<GetNHistos();i++) delete fHistodEdx[i]; | |
99 | delete [] fHistodEdx; | |
100 | fHistodEdx=0; | |
101 | } | |
102 | if(fHistoDeltadEdx){ | |
103 | for(Int_t i=0; i<GetNHistos();i++) delete fHistoDeltadEdx[i]; | |
104 | delete [] fHistoDeltadEdx; | |
105 | fHistoDeltadEdx=0; | |
106 | } | |
107 | if(fHistodEdxVsP){ | |
108 | for(Int_t i=0; i<GetNHistos2();i++) delete fHistodEdxVsP[i]; | |
109 | delete [] fHistodEdxVsP; | |
110 | fHistodEdxVsP=0; | |
111 | } | |
112 | } | |
113 | //______________________________________________________________________ | |
114 | void AliITSdEdxAnalyzer::BookHistos(){ | |
b34fed4e | 115 | // defines the output histograms |
75c74fab | 116 | fHistodEdx=new TH1F*[GetNHistos()]; |
117 | fHistoDeltadEdx=new TH1F*[GetNHistos()]; | |
118 | for(Int_t iSpecie=0; iSpecie<kNParticles; iSpecie++){ | |
119 | for(Int_t iPBin=0; iPBin<fNPBins; iPBin++){ | |
120 | for(Int_t iVal=0; iVal<kNValuesdEdx; iVal++){ | |
121 | TString hisnam1=Form("hdEdx%dpbin%dpart%d",fgkLayerCode[iVal],iPBin,fgkPdgCode[iSpecie]); | |
122 | TString histit1=Form("dEdx layer %d (keV) pbin%d part%d",fgkLayerCode[iVal],iPBin,fgkPdgCode[iSpecie]); | |
123 | if(iVal==kNValuesdEdx-1) histit1=Form("dEdx trunc. mean (keV) pbin%d part%d",iPBin,fgkPdgCode[iSpecie]); | |
124 | fHistodEdx[GetIndex(iSpecie,iPBin,iVal)]=new TH1F(hisnam1.Data(),histit1.Data(),100,0.,500.); | |
125 | fHistodEdx[GetIndex(iSpecie,iPBin,iVal)]->GetXaxis()->SetTitle(histit1.Data()); | |
126 | TString hisnam2=Form("hdeltadEdx%dpbin%dpart%d",fgkLayerCode[iVal],iPBin,fgkPdgCode[iSpecie]); | |
127 | TString histit2=Form("(dEdx_l%d-BetheBloch)/BetheBloch pbin%d part%d",fgkLayerCode[iVal],iPBin,fgkPdgCode[iSpecie]); | |
128 | if(iVal==kNValuesdEdx-1) histit1=Form("(dEdx_truncmean-BetheBloch)/BetheBloch pbin%d part%d",iPBin,fgkPdgCode[iSpecie]); | |
129 | fHistoDeltadEdx[GetIndex(iSpecie,iPBin,iVal)]=new TH1F(hisnam2.Data(),histit2.Data(),100,-0.5,0.5); | |
130 | fHistoDeltadEdx[GetIndex(iSpecie,iPBin,iVal)]->GetXaxis()->SetTitle(histit2.Data()); | |
131 | } | |
132 | } | |
133 | } | |
134 | ||
135 | fHistodEdxVsP=new TH2F*[GetNHistos2()]; | |
136 | for(Int_t iSpecie=0; iSpecie<kNParticles; iSpecie++){ | |
137 | for(Int_t iVal=0; iVal<kNValuesdEdx; iVal++){ | |
138 | TString hisnam=Form("hdEdx%dVsPpart%d",fgkLayerCode[iVal],fgkPdgCode[iSpecie]); | |
139 | TString histit=Form("dEdx layer %d (keV) vs P part%d",fgkLayerCode[iVal],fgkPdgCode[iSpecie]); | |
140 | if(iVal==kNValuesdEdx-1) histit=Form("dEdx trunc. mean (keV) vs P part%d",fgkPdgCode[iSpecie]); | |
141 | fHistodEdxVsP[GetIndex2(iSpecie,iVal)]=new TH2F(hisnam.Data(),histit.Data(),50,fPMin,fPMax,50,0.,500.); | |
142 | histit.ReplaceAll(" vs P "," "); | |
143 | fHistodEdxVsP[GetIndex2(iSpecie,iVal)]->GetYaxis()->SetTitle(histit.Data()); | |
144 | fHistodEdxVsP[GetIndex2(iSpecie,iVal)]->GetXaxis()->SetTitle("Momentum (GeV/c)"); | |
145 | } | |
146 | } | |
147 | } | |
148 | //______________________________________________________________________ | |
149 | void AliITSdEdxAnalyzer:: WriteHistos(TString filename) const { | |
b34fed4e | 150 | // stores output histogrma to file |
75c74fab | 151 | TFile *outfile=new TFile(filename.Data(),"recreate"); |
152 | outfile->cd(); | |
153 | for(Int_t i=0; i<GetNHistos();i++){ | |
154 | fHistodEdx[i]->Write(); | |
155 | fHistoDeltadEdx[i]->Write(); | |
156 | } | |
157 | for(Int_t i=0; i<GetNHistos2();i++) fHistodEdxVsP[i]->Write(); | |
158 | outfile->Close(); | |
159 | delete outfile; | |
160 | } | |
161 | //______________________________________________________________________ | |
b34fed4e | 162 | void AliITSdEdxAnalyzer::ReadEvent(const AliESDEvent* esd, AliStack* stack){ |
75c74fab | 163 | // Fill histos |
164 | // if stack is !=0 MC truth is used to define particle specie | |
165 | // else TPC pid is used to define particle specie | |
166 | ||
167 | if(!esd) AliFatal("Bad ESD event"); | |
168 | for (Int_t iTrack = 0; iTrack < esd->GetNumberOfTracks(); iTrack++) { | |
169 | AliESDtrack* track = esd->GetTrack(iTrack); | |
170 | Double_t trmean=track->GetITSsignal(); | |
171 | Double_t sig[4]; | |
172 | track->GetITSdEdxSamples(sig); | |
173 | Double_t preco=track->P(); | |
174 | Int_t iPBin=GetMomentumBin(preco); | |
175 | if(iPBin==-1) continue; | |
176 | Int_t iSpecie=-1; | |
177 | Double_t dedxbb=0; | |
178 | if(stack){ | |
179 | Int_t lab=track->GetLabel(); | |
180 | if(lab<0) continue; | |
181 | TParticle* part=(TParticle*)stack->Particle(lab); | |
182 | Int_t absPdgCode=TMath::Abs(part->GetPdgCode()); | |
183 | iSpecie=GetSpecieBin(absPdgCode); | |
184 | if(iSpecie==-1) continue; | |
185 | dedxbb=BetheBloch(part); | |
186 | }else{ | |
187 | iSpecie=GetPaticleIdFromTPC(track); | |
188 | if(iSpecie==-1) continue; | |
189 | TParticlePDG* p=TDatabasePDG::Instance()->GetParticle(fgkPdgCode[iSpecie]); | |
190 | dedxbb=BetheBloch(preco,p->Mass()); | |
191 | } | |
192 | for(Int_t ilay=0;ilay<4;ilay++){ | |
193 | if(sig[ilay]>0.){ | |
194 | fHistodEdx[GetIndex(iSpecie,iPBin,ilay)]->Fill(sig[ilay]); | |
195 | fHistoDeltadEdx[GetIndex(iSpecie,iPBin,ilay)]->Fill((sig[ilay]-dedxbb)/dedxbb); | |
196 | fHistodEdxVsP[GetIndex2(iSpecie,ilay)]->Fill(preco,sig[ilay]); | |
197 | } | |
198 | } | |
199 | if(trmean>0.){ | |
200 | fHistodEdx[GetIndex(iSpecie,iPBin,4)]->Fill(trmean); | |
201 | fHistoDeltadEdx[GetIndex(iSpecie,iPBin,4)]->Fill((trmean-dedxbb)/dedxbb); | |
202 | fHistodEdxVsP[GetIndex2(iSpecie,4)]->Fill(preco,trmean); | |
203 | } | |
204 | } | |
205 | } | |
206 | //______________________________________________________________________ | |
207 | Int_t AliITSdEdxAnalyzer::GetPaticleIdFromTPC(const AliESDtrack* track) const { | |
b34fed4e | 208 | // Returns the particle specie as identified by TPC |
75c74fab | 209 | Double_t tpcpid[AliPID::kSPECIES]; |
210 | track->GetTPCpid(tpcpid); | |
211 | Int_t maxPos=-1; | |
212 | Float_t maxProb=0.; | |
213 | for(Int_t is=0; is<AliPID::kSPECIES; is++){ | |
214 | if(tpcpid[is]>maxProb){ | |
215 | maxProb=tpcpid[is]; | |
216 | maxPos=is; | |
217 | } | |
218 | } | |
219 | Int_t iSpecie=-1; | |
220 | if(maxProb>fTPCpidCut){ | |
221 | if(maxPos==AliPID::kPion) iSpecie=0; | |
222 | else if(maxPos==AliPID::kKaon) iSpecie=1; | |
223 | else if(maxPos==AliPID::kProton) iSpecie=2; | |
224 | } | |
225 | return iSpecie; | |
226 | } | |
227 | //______________________________________________________________________ | |
228 | Double_t AliITSdEdxAnalyzer::BetheBloch(const Float_t p, const Float_t m) const { | |
b34fed4e | 229 | // Computes expected dE/dx value for given particle specie and momentum |
10d100d4 | 230 | static AliITSPIDResponse pidResponse; |
75c74fab | 231 | Double_t dedxbb=0.; |
26964b7f | 232 | if(fBBmodel==0){ |
75c74fab | 233 | Double_t betagamma=p/m; |
b89be497 | 234 | Double_t conv=fDensity*1E6*fThickness/116.24*fMIP; |
75c74fab | 235 | dedxbb=conv*AliExternalTrackParam::BetheBlochSolid(betagamma); |
26964b7f | 236 | }else if(fBBmodel==1){ |
10d100d4 | 237 | dedxbb=pidResponse.Bethe(p,m); |
75c74fab | 238 | } |
239 | return dedxbb; | |
240 | } | |
241 | //______________________________________________________________________ | |
242 | TGraph* AliITSdEdxAnalyzer::GetBetheBlochGraph(const Int_t pdgcode) const { | |
b246a937 | 243 | // Fills a TGraph with Bethe-Bloch expe |
244 | TGraph* g=new TGraph(0); | |
245 | TParticlePDG* part=TDatabasePDG::Instance()->GetParticle(pdgcode); | |
246 | Float_t mass=part->Mass(); | |
247 | for(Int_t ip=0; ip<100;ip++){ | |
248 | Float_t p=fPMin+(ip+0.5)*(fPMax-fPMin)/100.; | |
249 | g->SetPoint(ip,p,BetheBloch(p,mass)); | |
250 | } | |
251 | g->GetXaxis()->SetTitle("Momentum (GeV/c)"); | |
252 | g->GetYaxis()->SetTitle("dE/dx (keV/300 #mum)"); | |
253 | return g; | |
75c74fab | 254 | } |