Classed moved form libJETANMC to libJETAN.
[u/mrichter/AliRoot.git] / JETAN / AliJetKineReader.cxx
CommitLineData
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>
99e5fe42 27#include <TLorentzVector.h>
28#include <TSystem.h>
29#include <TDatabasePDG.h>
30#include <TRandom.h>
31// From AliRoot ...
85575952 32#include "AliAODJet.h"
99e5fe42 33#include "AliJetKineReaderHeader.h"
34#include "AliJetKineReader.h"
85575952 35#include "AliMCEventHandler.h"
99e5fe42 36#include "AliStack.h"
0ffa8579 37#include "AliHeader.h"
38#include "AliGenPythiaEventHeader.h"
85575952 39#include "AliLog.h"
99e5fe42 40
41ClassImp(AliJetKineReader)
42
1b7d5d7e 43AliJetKineReader::AliJetKineReader():
b45b0c92 44 AliJetReader(),
85575952 45 fAliHeader(0),
46 fMCEventHandler(0),
47 fGenJets(0)
99e5fe42 48{
1b7d5d7e 49 // Default constructor
99e5fe42 50}
51
52//____________________________________________________________________________
53
54AliJetKineReader::~AliJetKineReader()
55{
56 // Destructor
0ffa8579 57 delete fAliHeader;
99e5fe42 58}
59
60//____________________________________________________________________________
61
62void AliJetKineReader::OpenInputFiles()
63{
83a444b1 64 // Opens the input file using the run loader
85575952 65 // Not used anymore
99e5fe42 66}
67
68//____________________________________________________________________________
69
0ffa8579 70Bool_t AliJetKineReader::FillMomentumArray(Int_t event)
99e5fe42 71{
83a444b1 72 // Fill momentum array for event
85575952 73 Int_t goodTrack = 0;
74 // Clear array
75 // temporary storage of signal and cut flags
76 Int_t* sflag = new Int_t[50000];
77 Int_t* cflag = new Int_t[50000];
83a444b1 78
85575952 79 ClearArray();
80 // Get the stack
81 AliStack* stack = fMCEventHandler->Stack();
82 // Number of primaries
83 Int_t nt = stack->GetNprimary();
4faf4c3d 84
85575952 85 // Get cuts set by user and header
86 Double_t ptMin = ((AliJetKineReaderHeader*) fReaderHeader)->GetPtCut();
87 Float_t etaMin = fReaderHeader->GetFiducialEtaMin();
88 Float_t etaMax = fReaderHeader->GetFiducialEtaMax();
89 fAliHeader = fMCEventHandler->Header();
4faf4c3d 90
85575952 91
92 TLorentzVector p4;
93 // Loop over particles
94 for (Int_t it = 0; it < nt; it++) {
95 TParticle *part = stack->Particle(it);
96 Int_t status = part->GetStatusCode();
97 Int_t pdg = TMath::Abs(part->GetPdgCode());
98 Float_t pt = part->Pt();
4faf4c3d 99
85575952 100 // Skip non-final state particles, neutrinos
101 // and particles with pt < pt_min
102 if ((status != 1)
103 || (pdg == 12 || pdg == 14 || pdg == 16)) continue;
104
105 Float_t p = part->P();
106 Float_t p0 = p;
107 Float_t eta = part->Eta();
108 Float_t phi = part->Phi();
109
110 // Fast simulation of TPC if requested
111 if (((AliJetKineReaderHeader*)fReaderHeader)->FastSimTPC()) {
112 // Charged particles only
113 Float_t charge =
114 TDatabasePDG::Instance()->GetParticle(pdg)->Charge();
115 if (charge == 0) continue;
116 // Simulate efficiency
117 if (!Efficiency(p0, eta, phi)) continue;
118 // Simulate resolution
119 p = SmearMomentum(4, p0);
120 } // End fast TPC
4faf4c3d 121
122 // Fast simulation of EMCAL if requested
85575952 123 if (((AliJetKineReaderHeader*)fReaderHeader)->FastSimEMCAL()) {
124 Float_t charge =
125 TDatabasePDG::Instance()->GetParticle(pdg)->Charge();
126 // Charged particles only
127 if (charge != 0){
128 // Simulate efficiency
129 if (!Efficiency(p0, eta, phi)) continue;
130 // Simulate resolution
131 p = SmearMomentum(4, p0);
132 } // end "if" charged particles
4faf4c3d 133 // Neutral particles (exclude K0L, n, nbar)
85575952 134 if (pdg == kNeutron || pdg == kK0Long) continue;
135 } // End fast EMCAL
136
4faf4c3d 137 // Fill momentum array
85575952 138 Float_t r = p/p0;
139 Float_t px = r * part->Px();
140 Float_t py = r * part->Py();
141 Float_t pz = r * part->Pz();
142 Float_t m = part->GetMass();
143 Float_t e = TMath::Sqrt(px * px + py * py + pz * pz + m * m);
144 p4 = TLorentzVector(px, py, pz, e);
145 if ( (p4.Eta()>etaMax) || (p4.Eta()<etaMin)) continue;
146 new ((*fMomentumArray)[goodTrack]) TLorentzVector(p4);
147
148 // all tracks are signal ... ?
149 sflag[goodTrack]=1;
150 cflag[goodTrack]=0;
151 if (pt > ptMin) cflag[goodTrack] = 1; // track surviving pt cut
152 goodTrack++;
153 } // track loop
154
155// set the signal flags
156 fSignalFlag.Set(goodTrack, sflag);
157 fCutFlag.Set(goodTrack, cflag);
158 AliInfo(Form("\n In event %d, number of good tracks %d \n", event, goodTrack));
159
160 delete[] sflag;
161 delete[] cflag;
162
163 return kTRUE;
99e5fe42 164}
165
166
48bb52d8 167Float_t AliJetKineReader::SmearMomentum(Int_t ind, Float_t p)
168{
83a444b1 169 // The relative momentum error, i.e.
170 // (delta p)/p = sqrt (a**2 + (b*p)**2) * 10**-2,
171 // where typically a = 0.75 and b = 0.16 - 0.24 depending on multiplicity
172 // (the lower value is for dn/d(eta) about 2000, and the higher one for 8000)
173 //
174 // If we include information from TRD, b will be a factor 2/3 smaller.
175 //
176 // ind = 1: high multiplicity
177 // ind = 2: low multiplicity
178 // ind = 3: high multiplicity + TRD
179 // ind = 4: low multiplicity + TRD
180
181 Float_t pSmeared;
182 Float_t a = 0.75;
183 Float_t b = 0.12;
184
185 if (ind == 1) b = 0.12;
186 if (ind == 2) b = 0.08;
187 if (ind == 3) b = 0.12;
188 if (ind == 4) b = 0.08;
189
190 Float_t sigma = p * TMath::Sqrt(a * a + b * b * p * p)*0.01;
191 pSmeared = p + gRandom->Gaus(0., sigma);
192 return pSmeared;
48bb52d8 193}
83a444b1 194
195
48bb52d8 196Bool_t AliJetKineReader::Efficiency(Float_t p, Float_t /*eta*/, Float_t phi)
197{
83a444b1 198 // Fast simulation of geometrical acceptance and tracking efficiency
199
200 // Tracking
201 Float_t eff = 0.99;
202 if (p < 0.5) eff -= (0.5-p)*0.2/0.3;
203 // Geometry
204 if (p > 0.5) {
205 phi *= 180. / TMath::Pi();
206 // Sector number 0 - 17
207 Int_t isec = Int_t(phi / 20.);
208 // Sector centre
209 Float_t phi0 = isec * 20. + 10.;
210 Float_t phir = TMath::Abs(phi-phi0);
211 // 2 deg of dead space
212 if (phir > 9.) eff = 0.;
213 }
214
215 if (gRandom->Rndm() > eff) {
216 return kFALSE;
217 } else {
218 return kTRUE;
219 }
220
48bb52d8 221}
222
85575952 223TClonesArray* AliJetKineReader::GetGeneratedJets()
0ffa8579 224{
85575952 225 //
0ffa8579 226 // Get generated jets from mc header
85575952 227 //
228 if (!fGenJets) {
229 fGenJets = new TClonesArray("AliAODJets", 100);
230 } else {
231 fGenJets->Clear();
232 }
233
234
0ffa8579 235 AliHeader* alih = GetAliHeader();
85575952 236 if (alih == 0) return 0;
0ffa8579 237 AliGenEventHeader * genh = alih->GenEventHeader();
85575952 238 if (genh == 0) return 0;
239
0ffa8579 240 Int_t nj =((AliGenPythiaEventHeader*)genh)->NTriggerJets();
85575952 241 for (Int_t i = 0; i < nj; i++) {
0ffa8579 242 Float_t p[4];
243 ((AliGenPythiaEventHeader*)genh)->TriggerJet(i,p);
85575952 244 new ((*fGenJets)[i]) AliAODJet(p[0], p[1], p[2], p[3]);
0ffa8579 245 }
85575952 246
247 return fGenJets;
248}
249
250void AliJetKineReader::SetInputEvent(TObject* /*esd*/, TObject* /*aod*/, TObject* mc)
251{
252 // Connect the input event
253 fMCEventHandler = (AliMCEventHandler*) mc;
0ffa8579 254}