1 /**************************************************************************
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4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
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12 * about the suitability of this software for any purpose. It is *
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14 **************************************************************************/
19 // Classe to create the coktail for physics with muons for pp at 14 TeV
20 // The followoing sources:
21 // jpsi,psiP, upsilon, upsilonP, upsilonPP are added to Pythia
22 // The free parameeters are :
23 // pp reaction cross-section
24 // production cross-sections in pp collisions
27 #include <TObjArray.h>
28 #include <TParticle.h>
31 #include "AliGenCocktailEventHeader.h"
33 #include "AliGenCocktailEntry.h"
34 #include "AliGenMUONCocktailpp.h"
35 #include "AliGenMUONlib.h"
36 #include "AliGenParam.h"
41 #include "AliGenPythia.h"
44 ClassImp(AliGenMUONCocktailpp)
46 //________________________________________________________________________
47 AliGenMUONCocktailpp::AliGenMUONCocktailpp()
59 //_________________________________________________________________________
60 AliGenMUONCocktailpp::AliGenMUONCocktailpp(const AliGenMUONCocktailpp & cocktail):
61 AliGenCocktail(cocktail),
79 //_________________________________________________________________________
80 AliGenMUONCocktailpp::~AliGenMUONCocktailpp()
86 //_________________________________________________________________________
87 void AliGenMUONCocktailpp::Init()
89 // MinBias NN cross section @ pp 14 TeV -PR Vol II p:473
90 Double_t sigmaReaction = 0.070;
92 // These limits are only used for renormalization of quarkonia cross section
93 // Pythia events are generated in 4pi
94 Double_t ptMin = fPtMin;
95 Double_t ptMax = fPtMax;
96 Double_t yMin = fYMin;;
97 Double_t yMax = fYMax;;
98 Double_t phiMin = fPhiMin*180./TMath::Pi();
99 Double_t phiMax = fPhiMax*180./TMath::Pi();
100 AliInfo(Form("Ranges pT:%4.1f : %4.1f GeV/c, y:%4.2f : %4.2f, Phi:%5.1f : %5.1f degres",ptMin,ptMax,yMin,yMax,phiMin,phiMax));
102 // Ratios with respect to the reaction cross-section in the
103 // kinematics limit of the MUONCocktail
106 Double_t ratioupsilon;
107 Double_t ratioupsilonP;
108 Double_t ratioupsilonPP;
110 // Cross sections in barns (from PPR Vol. II p: 552) pp - 14 TeV and
111 // corrected from feed down of higher resonances
113 Double_t sigmajpsi = 49.44e-6;
114 Double_t sigmapsiP = 7.67e-6;
115 Double_t sigmaupsilon = 0.989e-6;
116 Double_t sigmaupsilonP = 0.502e-6;
117 Double_t sigmaupsilonPP = 0.228e-6;
119 // Generation using CDF scaled distribution for pp@14TeV (from D. Stocco)
120 //----------------------------------------------------------------------
122 AliGenParam * genjpsi = new AliGenParam(1, AliGenMUONlib::kJpsi, "CDF pp", "Jpsi");
123 // first step: generation in 4pi
124 genjpsi->SetPtRange(0.,100.);
125 genjpsi->SetYRange(-8.,8.);
126 genjpsi->SetPhiRange(0.,360.);
127 genjpsi->SetForceDecay(kAll);
128 genjpsi->Init(); // generation in 4pi
129 ratiojpsi = sigmajpsi / sigmaReaction * genjpsi->GetRelativeArea(ptMin,ptMax,yMin,yMax,phiMin,phiMax); // get weight
130 AliInfo(Form("jpsi prod. cross-section in pp(14 TeV) %5.3g b",sigmajpsi));
131 AliInfo(Form("jpsi prod. probability per collision in acceptance %5.3g",ratiojpsi));
132 // second step: generation in selected kinematical range
133 genjpsi->SetPtRange(ptMin, ptMax);
134 genjpsi->SetYRange(yMin, yMax);
135 genjpsi->SetPhiRange(phiMin, phiMax);
136 genjpsi->Init(); // generation in selected kinematic range
137 AddGenerator(genjpsi, "Jpsi", ratiojpsi); // Adding Generator
138 fTotalRate+=ratiojpsi;
140 //------------------------------------------------------------------
141 // Psi prime generator
142 AliGenParam * genpsiP = new AliGenParam(1, AliGenMUONlib::kPsiP, "CDF pp", "PsiP");
143 // first step: generation in 4pi
144 genpsiP->SetPtRange(0.,100.);
145 genpsiP->SetYRange(-8.,8.);
146 genpsiP->SetPhiRange(0.,360.);
147 genpsiP->SetForceDecay(kAll);
148 genpsiP->Init(); // generation in 4pi
149 ratiopsiP = sigmapsiP / sigmaReaction * genpsiP->GetRelativeArea(ptMin,ptMax,yMin,yMax,phiMin,phiMax);
150 AliInfo(Form("psiP prod. cross-section in pp(14 TeV) %5.3g b",sigmapsiP));
151 AliInfo(Form("psiP prod. probability per collision in acceptance %5.3g",ratiopsiP));
152 // second step: generation in selected kinematical range
153 genpsiP->SetPtRange(ptMin, ptMax);
154 genpsiP->SetYRange(yMin, yMax);
155 genpsiP->SetPhiRange(phiMin, phiMax);
156 genpsiP->Init(); // generation in selected kinematic range
157 AddGenerator(genpsiP, "PsiP", ratiopsiP); // Adding Generator
158 fTotalRate+=ratiopsiP;
160 //------------------------------------------------------------------
161 // Upsilon 1S generator
162 AliGenParam * genupsilon = new AliGenParam(1, AliGenMUONlib::kUpsilon, "CDF pp", "Upsilon");
163 // first step: generation in 4pi
164 genupsilon->SetPtRange(0.,100.);
165 genupsilon->SetYRange(-8.,8.);
166 genupsilon->SetPhiRange(0.,360.);
167 genupsilon->SetForceDecay(kAll);
168 genupsilon->Init(); // generation in 4pi
169 ratioupsilon = sigmaupsilon / sigmaReaction * genupsilon->GetRelativeArea(ptMin,ptMax,yMin,yMax,phiMin,phiMax);
170 AliInfo(Form("Upsilon 1S prod. cross-section in pp(14 TeV) %5.3g b",sigmaupsilon));
171 AliInfo(Form("Upsilon 1S prod. probability per collision in acceptance %5.3g",ratioupsilon));
172 // second step: generation in selected kinematical range
173 genupsilon->SetPtRange(ptMin, ptMax);
174 genupsilon->SetYRange(yMin, yMax);
175 genupsilon->SetPhiRange(phiMin, phiMax);
176 genupsilon->Init(); // generation in selected kinematical range
177 AddGenerator(genupsilon,"Upsilon", ratioupsilon); // Adding Generator
178 fTotalRate+=ratioupsilon;
180 //------------------------------------------------------------------
181 // Upsilon 2S generator
182 AliGenParam * genupsilonP = new AliGenParam(1, AliGenMUONlib::kUpsilonP, "CDF pp", "UpsilonP");
183 // first step: generation in 4pi
184 genupsilonP->SetPtRange(0.,100.);
185 genupsilonP->SetYRange(-8.,8.);
186 genupsilonP->SetPhiRange(0.,360.);
187 genupsilonP->SetForceDecay(kAll);
188 genupsilonP->Init(); // generation in 4pi
189 ratioupsilonP = sigmaupsilonP / sigmaReaction * genupsilonP->GetRelativeArea(ptMin,ptMax,yMin,yMax,phiMin,phiMax);
190 AliInfo(Form("Upsilon 2S prod. cross-section in pp(14 TeV) %5.3g b",sigmaupsilonP));
191 AliInfo(Form("Upsilon 2S prod. probability per collision in acceptance %5.3g",ratioupsilonP));
192 // second step: generation in the kinematical range
193 genupsilonP->SetPtRange(ptMin, ptMax);
194 genupsilonP->SetYRange(yMin, yMax);
195 genupsilonP->SetPhiRange(phiMin, phiMax);
196 genupsilonP->Init(); // generation in selected kinematical range
197 AddGenerator(genupsilonP,"UpsilonP", ratioupsilonP); // Adding Generator
198 fTotalRate+=ratioupsilonP;
200 //------------------------------------------------------------------
201 // Upsilon 3S generator
202 AliGenParam * genupsilonPP = new AliGenParam(1, AliGenMUONlib::kUpsilonPP, "CDF pp", "UpsilonPP");
203 // first step: generation in 4pi
204 genupsilonPP->SetPtRange(0.,100.);
205 genupsilonPP->SetYRange(-8.,8.);
206 genupsilonPP->SetPhiRange(0.,360.);
207 genupsilonPP->SetForceDecay(kAll);
208 genupsilonPP->Init(); // generation in 4pi
209 ratioupsilonPP = sigmaupsilonPP / sigmaReaction * genupsilonPP->GetRelativeArea(ptMin,ptMax,yMin,yMax,phiMin,phiMax);
210 AliInfo(Form("Upsilon 3S prod. cross-section in pp(14 TeV) %5.3g b",sigmaupsilonPP));
211 AliInfo(Form("Upsilon 3S prod. probability per collision in acceptance %5.3g",ratioupsilonPP));
212 // second step: generation in selected kinematical range
213 genupsilonPP->SetPtRange(ptMin, ptMax);
214 genupsilonPP->SetYRange(yMin, yMax);
215 genupsilonPP->SetPhiRange(phiMin, phiMax);
216 genupsilonPP->Init(); // generation in selected kinematical range
217 AddGenerator(genupsilonPP,"UpsilonPP", ratioupsilonPP); // Adding Generator
218 fTotalRate+=ratioupsilonPP;
220 //------------------------------------------------------------------
222 AliGenPythia *pythia = new AliGenPythia(1);
223 pythia->SetProcess(kPyMbMSEL1);
224 pythia->SetStrucFunc(kCTEQ5L);
225 pythia->SetEnergyCMS(14000.);
226 pythia->SetForceDecay(kAll);
227 pythia->SetPtRange(0.,100.);
228 pythia->SetYRange(-8.,8.);
229 pythia->SetPhiRange(0.,360.);
230 pythia->SetPtHard(2.76,-1.0);
232 AddGenerator(pythia,"Pythia",1);
237 //_________________________________________________________________________
238 void AliGenMUONCocktailpp::Generate()
241 TIter next(fEntries);
242 AliGenCocktailEntry *entry = 0;
243 AliGenCocktailEntry *preventry = 0;
244 AliGenerator* gen = 0;
246 TObjArray *partArray = gAlice->GetMCApp()->Particles();
248 // Generate the vertex position used by all generators
249 if(fVertexSmear == kPerEvent) Vertex();
251 // Loop on primordialTrigger:
252 // minimum muon multiplicity above a pt cut in a theta acceptance region
254 Bool_t primordialTrigger = kFALSE;
255 while(!primordialTrigger) {
257 AliRunLoader * runloader = gAlice->GetRunLoader();
259 if (runloader->Stack())
260 runloader->Stack()->Reset();
261 // Loop over generators and generate events
264 const char* genName = 0;
265 while((entry = (AliGenCocktailEntry*)next())) {
266 gen = entry->Generator();
267 genName = entry->GetName();
268 gen->SetVertex(fVertex.At(0), fVertex.At(1), fVertex.At(2));
270 npart = (strcmp(genName,"Pythia") == 0) ? 1 :
271 gRandom->Poisson(entry->Rate());
275 if (igen == 1) entry->SetFirst(0);
276 else entry->SetFirst((partArray->GetEntriesFast())+1);
278 gen->SetNumberParticles(npart);
280 entry->SetLast(partArray->GetEntriesFast());
286 // Testing primordial trigger: Single muons or dimuons with Pt above a Pt cut
287 // in the muon spectrometer acceptance
290 Int_t numberOfMuons=0;
292 for(iPart=0; iPart<partArray->GetEntriesFast(); iPart++){
294 if ( (TMath::Abs(gAlice->GetMCApp()->Particle(iPart)->GetPdgCode())==13) &&
295 (gAlice->GetMCApp()->Particle(iPart)->Theta()*180./TMath::Pi()>fMuonThetaMinCut) &&
296 (gAlice->GetMCApp()->Particle(iPart)->Theta()*180./TMath::Pi()<fMuonThetaMaxCut) &&
297 (gAlice->GetMCApp()->Particle(iPart)->Pt()>fMuonPtCut) ) {
303 if (numberOfMuons >= fMuonMultiplicity) primordialTrigger = kTRUE;
307 AliInfo(Form("Generated Events are %d and Succeeded Events are %d",fNGenerated,fNSucceded));
308 AliDebug(5,Form("Generated Events are %d and Succeeded Events are %d",fNGenerated,fNSucceded));