]>
Commit | Line | Data |
---|---|---|
99e5fe42 | 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 | ||
83a444b1 | 16 | //------------------------------------------------------------------------- |
99e5fe42 | 17 | // Jet kinematics reader |
18 | // MC reader for jet analysis | |
83a444b1 | 19 | // Author: Andreas Morsch (andreas.morsch@cern.ch) |
20 | //------------------------------------------------------------------------- | |
99e5fe42 | 21 | |
22 | // From root ... | |
23 | #include <TClonesArray.h> | |
24 | #include <TPDGCode.h> | |
25 | #include <TParticle.h> | |
26 | #include <TParticlePDG.h> | |
83a444b1 | 27 | //#include <TVector3.h> |
99e5fe42 | 28 | #include <TLorentzVector.h> |
29 | #include <TSystem.h> | |
30 | #include <TDatabasePDG.h> | |
31 | #include <TRandom.h> | |
32 | // From AliRoot ... | |
33 | #include "AliJetKineReaderHeader.h" | |
34 | #include "AliJetKineReader.h" | |
35 | #include "AliRunLoader.h" | |
36 | #include "AliStack.h" | |
37 | ||
38 | ClassImp(AliJetKineReader) | |
39 | ||
1b7d5d7e | 40 | AliJetKineReader::AliJetKineReader(): |
41 | fRunLoader(0x0), | |
42 | fMass(0), | |
43 | fPdgC(0) | |
99e5fe42 | 44 | { |
1b7d5d7e | 45 | // Default constructor |
99e5fe42 | 46 | fReaderHeader = 0x0; |
99e5fe42 | 47 | } |
48 | ||
49 | //____________________________________________________________________________ | |
50 | ||
51 | AliJetKineReader::~AliJetKineReader() | |
52 | { | |
53 | // Destructor | |
54 | delete fReaderHeader; | |
55 | } | |
56 | ||
57 | //____________________________________________________________________________ | |
58 | ||
59 | void AliJetKineReader::OpenInputFiles() | |
60 | { | |
83a444b1 | 61 | // Opens the input file using the run loader |
62 | const char* dirName = fReaderHeader->GetDirectory(); | |
63 | char path[256]; | |
64 | sprintf(path, "%s/galice.root",dirName); | |
65 | fRunLoader = AliRunLoader::Open(path); | |
66 | fRunLoader->LoadKinematics(); | |
67 | fRunLoader->LoadHeader(); | |
68 | ||
69 | // get number of events | |
70 | Int_t nMax = fRunLoader->GetNumberOfEvents(); | |
71 | printf("\nTotal number of events = %d", nMax); | |
72 | ||
99e5fe42 | 73 | // set number of events in header |
83a444b1 | 74 | if (fReaderHeader->GetLastEvent() == -1) |
75 | fReaderHeader->SetLastEvent(nMax); | |
76 | else { | |
77 | Int_t nUsr = fReaderHeader->GetLastEvent(); | |
78 | fReaderHeader->SetLastEvent(TMath::Min(nMax, nUsr)); | |
79 | } | |
99e5fe42 | 80 | } |
81 | ||
82 | //____________________________________________________________________________ | |
83 | ||
84 | void AliJetKineReader::FillMomentumArray(Int_t event) | |
85 | { | |
83a444b1 | 86 | // Fill momentum array for event |
87 | ||
88 | Int_t goodTrack = 0; | |
89 | // Clear array | |
90 | ClearArray(); | |
91 | // Get event from runloader | |
92 | fRunLoader->GetEvent(event); | |
93 | // Get the stack | |
94 | AliStack* stack = fRunLoader->Stack(); | |
95 | // Number of primaries | |
96 | Int_t nt = stack->GetNprimary(); | |
97 | ||
98 | // Get cuts set by user and header | |
99 | Double_t ptMin = ((AliJetKineReaderHeader*) fReaderHeader)->GetPtCut(); | |
100 | Float_t etaMin = fReaderHeader->GetFiducialEtaMin(); | |
101 | Float_t etaMax = fReaderHeader->GetFiducialEtaMax(); | |
102 | fAliHeader = fRunLoader->GetHeader(); | |
103 | ||
104 | // temporary storage of signal and cut flags | |
105 | Int_t* sflag = new Int_t[nt]; | |
106 | Int_t* cflag = new Int_t[nt]; | |
107 | ||
108 | TLorentzVector p4; | |
109 | // Loop over particles | |
110 | for (Int_t it = 0; it < nt; it++) { | |
111 | TParticle *part = stack->Particle(it); | |
112 | Int_t status = part->GetStatusCode(); | |
113 | Int_t pdg = TMath::Abs(part->GetPdgCode()); | |
114 | Float_t pt = part->Pt(); | |
115 | ||
116 | // Skip non-final state particles, neutrinos | |
117 | // and particles with pt < pt_min | |
118 | if ((status != 1) | |
119 | || (pdg == 12 || pdg == 14 || pdg == 16)) continue; | |
120 | ||
121 | Float_t p = part->P(); | |
122 | Float_t p0 = p; | |
123 | Float_t eta = part->Eta(); | |
124 | Float_t phi = part->Phi(); | |
125 | ||
126 | // Fast simulation of TPC if requested | |
127 | if (((AliJetKineReaderHeader*)fReaderHeader)->FastSimTPC()) { | |
128 | // Charged particles only | |
129 | Float_t charge = | |
130 | TDatabasePDG::Instance()->GetParticle(pdg)->Charge(); | |
131 | if (charge == 0) continue; | |
132 | // Simulate efficiency | |
133 | if (!Efficiency(p0, eta, phi)) continue; | |
134 | // Simulate resolution | |
135 | p = SmearMomentum(4, p0); | |
136 | } // End fast TPC | |
137 | ||
138 | // Fast simulation of EMCAL if requested | |
139 | if (((AliJetKineReaderHeader*)fReaderHeader)->FastSimEMCAL()) { | |
140 | Float_t charge = | |
141 | TDatabasePDG::Instance()->GetParticle(pdg)->Charge(); | |
142 | // Charged particles only | |
143 | if (charge != 0){ | |
144 | // Simulate efficiency | |
145 | if (!Efficiency(p0, eta, phi)) continue; | |
146 | // Simulate resolution | |
147 | p = SmearMomentum(4, p0); | |
148 | } // end "if" charged particles | |
149 | // Neutral particles (exclude K0L, n, nbar) | |
150 | if (pdg == kNeutron || pdg == kK0Long) continue; | |
151 | } // End fast EMCAL | |
152 | ||
153 | fMass = part->GetCalcMass(); | |
154 | fPdgC = part->GetPdgCode(); | |
155 | ||
156 | // Fill momentum array | |
157 | Float_t r = p/p0; | |
158 | Float_t px = r * part->Px(); | |
159 | Float_t py = r * part->Py(); | |
160 | Float_t pz = r * part->Pz(); | |
161 | Float_t m = part->GetMass(); | |
162 | Float_t e = TMath::Sqrt(px * px + py * py + pz * pz + m * m); | |
163 | p4 = TLorentzVector(px, py, pz, e); | |
164 | if ( (p4.Eta()>etaMax) || (p4.Eta()<etaMin)) continue; | |
165 | new ((*fMomentumArray)[goodTrack]) TLorentzVector(p4); | |
166 | ||
167 | // all tracks are signal ... ? | |
168 | sflag[goodTrack]=1; | |
169 | cflag[goodTrack]=0; | |
170 | if (pt > ptMin) cflag[goodTrack]=1; // track surviving pt cut | |
171 | goodTrack++; | |
99e5fe42 | 172 | } |
83a444b1 | 173 | |
174 | // set the signal flags | |
175 | fSignalFlag.Set(goodTrack,sflag); | |
176 | fCutFlag.Set(goodTrack,cflag); | |
177 | printf("\nIn event %d, number of good tracks %d \n", event, goodTrack); | |
178 | ||
99e5fe42 | 179 | } |
180 | ||
181 | ||
48bb52d8 | 182 | Float_t AliJetKineReader::SmearMomentum(Int_t ind, Float_t p) |
183 | { | |
83a444b1 | 184 | // The relative momentum error, i.e. |
185 | // (delta p)/p = sqrt (a**2 + (b*p)**2) * 10**-2, | |
186 | // where typically a = 0.75 and b = 0.16 - 0.24 depending on multiplicity | |
187 | // (the lower value is for dn/d(eta) about 2000, and the higher one for 8000) | |
188 | // | |
189 | // If we include information from TRD, b will be a factor 2/3 smaller. | |
190 | // | |
191 | // ind = 1: high multiplicity | |
192 | // ind = 2: low multiplicity | |
193 | // ind = 3: high multiplicity + TRD | |
194 | // ind = 4: low multiplicity + TRD | |
195 | ||
196 | Float_t pSmeared; | |
197 | Float_t a = 0.75; | |
198 | Float_t b = 0.12; | |
199 | ||
200 | if (ind == 1) b = 0.12; | |
201 | if (ind == 2) b = 0.08; | |
202 | if (ind == 3) b = 0.12; | |
203 | if (ind == 4) b = 0.08; | |
204 | ||
205 | Float_t sigma = p * TMath::Sqrt(a * a + b * b * p * p)*0.01; | |
206 | pSmeared = p + gRandom->Gaus(0., sigma); | |
207 | return pSmeared; | |
48bb52d8 | 208 | } |
83a444b1 | 209 | |
210 | ||
48bb52d8 | 211 | Bool_t AliJetKineReader::Efficiency(Float_t p, Float_t /*eta*/, Float_t phi) |
212 | { | |
83a444b1 | 213 | // Fast simulation of geometrical acceptance and tracking efficiency |
214 | ||
215 | // Tracking | |
216 | Float_t eff = 0.99; | |
217 | if (p < 0.5) eff -= (0.5-p)*0.2/0.3; | |
218 | // Geometry | |
219 | if (p > 0.5) { | |
220 | phi *= 180. / TMath::Pi(); | |
221 | // Sector number 0 - 17 | |
222 | Int_t isec = Int_t(phi / 20.); | |
223 | // Sector centre | |
224 | Float_t phi0 = isec * 20. + 10.; | |
225 | Float_t phir = TMath::Abs(phi-phi0); | |
226 | // 2 deg of dead space | |
227 | if (phir > 9.) eff = 0.; | |
228 | } | |
229 | ||
230 | if (gRandom->Rndm() > eff) { | |
231 | return kFALSE; | |
232 | } else { | |
233 | return kTRUE; | |
234 | } | |
235 | ||
48bb52d8 | 236 | } |
237 |