Integration precission set to 1e-6. (G. Martinez)
[u/mrichter/AliRoot.git] / EVGEN / AliGenMUONCocktail.cxx
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4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
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15
16/* $Id$ */
17
9538aedd 18//
84954c47 19// Classe to create the MUON coktail for physics in the Alice muon spectrometer
9538aedd 20// The followoing muons sources are included in this cocktail:
17016a57 21// jpsi, upsilon, non-correlated open and beauty.
9538aedd 22// The free parameeters are :
23// pp reaction cross-section
24// production cross-sections in pp collisions and
17016a57 25// branching ratios in the muon channel and shadowing
26// Hard probes are supposed to scale with Ncoll and hadronic muon production with (0.8Ncoll+0.2*Npart)
27// There is a primordial trigger which requires :
9538aedd 28// a minimum muon multiplicity above a pT cut in a theta acceptance cone
29//
30// Gines Martinez, jan 2004, Nantes martinez@in2p3.fr
17016a57 31// Gines Martinez sep 2004, Nantes martinez@in2p3.fr
32//
84954c47 33//
34
84954c47 35#include <TObjArray.h>
84954c47 36#include <TParticle.h>
17016a57 37#include <TF1.h>
84954c47 38
84954c47 39#include "AliGenCocktailEntry.h"
ac3faee4 40#include "AliGenMUONCocktail.h"
41#include "AliGenMUONlib.h"
17016a57 42#include "AliFastGlauber.h"
ac3faee4 43#include "AliGenParam.h"
84954c47 44#include "AliMC.h"
ac3faee4 45#include "AliRun.h"
84954c47 46#include "AliStack.h"
17016a57 47#include "AliLog.h"
84954c47 48
49ClassImp(AliGenMUONCocktail)
50
51
52//________________________________________________________________________
53AliGenMUONCocktail::AliGenMUONCocktail()
54 :AliGenCocktail()
55{
56// Constructor
17016a57 57 fFastGlauber =0x0;
84954c47 58 fTotalRate =0;
59 fNSucceded=0;
60 fNGenerated=0;
61 fMuonMultiplicity=1;
62 fMuonPtCut= 1.;
63 fMuonThetaMinCut=171.;
64 fMuonThetaMaxCut=178.;
17016a57 65 fLowImpactParameter = 0.;
66 fHighImpactParameter = 5.;
67 fAverageImpactParameter =0.;
68 fNumberOfCollisions = 0.;
69 fNumberOfParticipants = 0.;
70 fHadronicMuons = kTRUE;
84954c47 71}
72//_________________________________________________________________________
73AliGenMUONCocktail::AliGenMUONCocktail(const AliGenMUONCocktail & cocktail):
74 AliGenCocktail(cocktail)
75{
76// Copy constructor
17016a57 77 fFastGlauber =0x0;
84954c47 78 fTotalRate =0;
79 fNSucceded=0;
80 fNGenerated=0;
81 fMuonMultiplicity=1;
82 fMuonPtCut= 1.;
83 fMuonThetaMinCut=171.;
17016a57 84 fMuonThetaMaxCut=178.;
85 fLowImpactParameter = 0.;
86 fHighImpactParameter = 5.;
87 fAverageImpactParameter =0.;
88 fNumberOfCollisions = 0.;
89 fNumberOfParticipants = 0.;
90 fHadronicMuons = kTRUE;
84954c47 91}
92//_________________________________________________________________________
93AliGenMUONCocktail::~AliGenMUONCocktail()
94{
95// Destructor
17016a57 96 if (fFastGlauber) delete fFastGlauber;
84954c47 97}
98
99//_________________________________________________________________________
100void AliGenMUONCocktail::Init()
101{
17016a57 102 // NN cross section
103 Double_t sigmaReaction = 0.072; // MinBias NN cross section for PbPb LHC energies http://arxiv.org/pdf/nucl-ex/0302016
104
105 // Initialising Fast Glauber object
106 fFastGlauber = new AliFastGlauber();
107 fFastGlauber->SetPbPbLHC();
108 fFastGlauber->SetNNCrossSection(sigmaReaction*1000.); //Expected NN cross-section in mb at LHC with diffractive part http://arxiv.org/pdf/nucl-ex/0302016 )
109 fFastGlauber->Init(1);
110
111 // Calculating average number of collisions
112 Int_t ib=0;
113 Int_t ibmax=10000;
114 Double_t b = 0.;
115 fAverageImpactParameter=0.;
116 fNumberOfCollisions = 0.;
117 fNumberOfParticipants = 0.;
118 for(ib=0; ib<ibmax; ib++) {
119 b = fFastGlauber->GetRandomImpactParameter(fLowImpactParameter,fHighImpactParameter);
120 fAverageImpactParameter+=b;
121 fNumberOfCollisions += fFastGlauber->GetNumberOfCollisions( b )/(1.-TMath::Exp(-fFastGlauber->GetNumberOfCollisions(b)));
122 fNumberOfParticipants += fFastGlauber->GetNumberOfParticipants( b );
123 }
124 fAverageImpactParameter/= ((Double_t) ibmax);
125 fNumberOfCollisions /= ((Double_t) ibmax);
126 fNumberOfParticipants /= ((Double_t) ibmax);;
127 AliInfo(Form("<b>=%4.2f, <Ncoll>=%5.1f and and <Npart>=%5.1f",b, fNumberOfCollisions, fNumberOfParticipants));
128
129 // Estimating shadowing on charm a beaty production
130 // -----------------------------------------------------
131 // Extrapolation of the cross sections from $p-p$ to \mbox{Pb--Pb}
132 // interactions
133 // is done by means of the Glauber model. For the impact parameter dependence
134 // of the shadowing factor we use a simple formula:
135 // $C_{sh}(b) = C_{sh}(0) + (1 - C_{sh}(0))(b/16~fm)4$,
136 // motivated by the theoretical predictions (see e.g.
137 // V. Emelyanov et al., Phys. Rev. C61, 044904 (2000)) and HIJING
138 // simulations showing an almost flat behaviour
139 // up to 10~$fm$ and a rapid increase to 1 for larger impact parameters.
140 // C_{sh}(0) = 0.60 for Psi and 0.76 for Upsilon (Smba communication).
141 // for open charm and beauty is 0.65 and 0.84
142 // -----------------------------------------------------
143 Double_t charmshadowing = 0.65 + (1.0-0.65)*TMath::Power(fAverageImpactParameter/16.,4);
144 Double_t beautyshadowing = 0.84 + (1.0-0.84)*TMath::Power(fAverageImpactParameter/16.,4);
145 Double_t charmoniumshadowing = 0.60 + (1.0-0.60)*TMath::Power(fAverageImpactParameter/16.,4);
146 Double_t beautoniumshadowing = 0.76 + (1.0-0.76)*TMath::Power(fAverageImpactParameter/16.,4);
147 if (fAverageImpactParameter>16.) {
148 charmoniumshadowing = 1.0;
149 beautoniumshadowing = 1.0;
150 charmshadowing = 1.0;
151 beautyshadowing= 1.0;
152 }
153 AliInfo(Form("Shadowing for charmonium and beautonium production are %4.2f and %4.2f respectively",charmoniumshadowing,beautoniumshadowing));
154 AliInfo(Form("Shadowing for charm and beauty production are %4.2f and %4.2f respectively",charmshadowing,beautyshadowing));
84954c47 155
17016a57 156 // Defining MUON physics cocktail
84954c47 157 // Kinematical limits for particle generation
17016a57 158 Double_t ptMin = fPtMin;
159 Double_t ptMax = fPtMax;
160 Double_t yMin = fYMin;;
161 Double_t yMax = fYMax;;
162 Double_t phiMin = fPhiMin*180./TMath::Pi();
163 Double_t phiMax = fPhiMax*180./TMath::Pi();
164 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));
165
166 // Generating J/Psi Physics
167 // Using Ramona Vogt distribution form CERN Yelow report and Andreas MORSCH private communication
9538aedd 168 AliGenParam * genjpsi = new AliGenParam(1, AliGenMUONlib::kJpsi, "Vogt", "Jpsi");
17016a57 169 genjpsi->SetPtRange(0,100.); // 4pi generation
9538aedd 170 genjpsi->SetYRange(-8.,8);
171 genjpsi->SetPhiRange(0.,360.);
172 genjpsi->SetForceDecay(kDiMuon);
173 genjpsi->SetTrackingFlag(1);
17016a57 174 // Calculation of the particle multiplicity per event in the muonic channel
175 Double_t ratiojpsi; // Ratio with respect to the reaction cross-section for the muonic channel in the kinematics limit of the MUONCocktail
176 Double_t sigmajpsi = 31.0e-6 * charmoniumshadowing; // section "6.7 Quarkonia Production" table 6.5 for pp times shadowing
177 Double_t brjpsi = 0.0588; // Branching Ratio for JPsi PDG PRC15 (200)
9538aedd 178 genjpsi->Init(); // Generating pT and Y parametrsation for the 4pi
179 ratiojpsi = sigmajpsi * brjpsi * fNumberOfCollisions / sigmaReaction * genjpsi->GetRelativeArea(ptMin,ptMax,yMin,yMax,phiMin,phiMax);
17016a57 180 AliInfo(Form("Jpsi production cross-section in pp with shadowing %5.3g barns",sigmajpsi));
181 AliInfo(Form("Jpsi production probability per collisions in acceptance via the muonic channel %5.3g",ratiojpsi));
84954c47 182 // Generation in the kinematical limits of AliGenMUONCocktail
9538aedd 183 genjpsi->SetPtRange(ptMin, ptMax);
184 genjpsi->SetYRange(yMin, yMax);
185 genjpsi->SetPhiRange(phiMin, phiMax);
186 genjpsi->Init(); // Generating pT and Y parametrsation in the desired kinematic range
84954c47 187 // Adding Generator
9538aedd 188 AddGenerator(genjpsi, "Jpsi", ratiojpsi);
189 fTotalRate+=ratiojpsi;
84954c47 190
88e5db43 191 // Generating Psi prime Physics
17016a57 192 // Using Ramona Vogt distribution form CERN Yelow report and Andreas MORSCH private communication
88e5db43 193 AliGenParam * genpsiP = new AliGenParam(1, AliGenMUONlib::kPsiP, "Vogt", "PsiP");
17016a57 194 genpsiP->SetPtRange(0,100.);// 4pi generation
88e5db43 195 genpsiP->SetYRange(-8.,8);
196 genpsiP->SetPhiRange(0.,360.);
197 genpsiP->SetForceDecay(kDiMuon);
198 genpsiP->SetTrackingFlag(1);
199 // Calculation of the paritcle multiplicity per event in the muonic channel
17016a57 200 Double_t ratiopsiP; // Ratio with respect to the reaction cross-section for the muonic channel in the kinematics limit of the MUONCocktail
201 Double_t sigmapsiP = 4.68e-6 * charmoniumshadowing; // section "6.7 Quarkonia Production" table 6.5 for pp times shadowing
202 Double_t brpsiP = 0.0103; // Branching Ratio for PsiP
88e5db43 203 genpsiP->Init(); // Generating pT and Y parametrsation for the 4pi
204 ratiopsiP = sigmapsiP * brpsiP * fNumberOfCollisions / sigmaReaction * genpsiP->GetRelativeArea(ptMin,ptMax,yMin,yMax,phiMin,phiMax);
17016a57 205 AliInfo(Form("Psi prime production cross-section in pp with shadowing %5.3g barns",sigmapsiP));
206 AliInfo(Form("Psi prime production probability per collisions in acceptance via the muonic channel %5.3g",ratiopsiP));
88e5db43 207 // Generation in the kinematical limits of AliGenMUONCocktail
208 genpsiP->SetPtRange(ptMin, ptMax);
209 genpsiP->SetYRange(yMin, yMax);
210 genpsiP->SetPhiRange(phiMin, phiMax);
211 genpsiP->Init(); // Generating pT and Y parametrsation in the desired kinematic range
212 // Adding Generator
213 AddGenerator(genpsiP, "PsiP", ratiopsiP);
214 fTotalRate+=ratiopsiP;
215
17016a57 216 // Generating Upsilon Physics
217 // Using Ramona Vogt distribution form CERN Yelow report and Andreas MORSCH private communication
9538aedd 218 AliGenParam * genupsilon = new AliGenParam(1, AliGenMUONlib::kUpsilon, "Vogt", "Upsilon");
219 genupsilon->SetPtRange(0,100.);
220 genupsilon->SetYRange(-8.,8);
221 genupsilon->SetPhiRange(0.,360.);
222 genupsilon->SetForceDecay(kDiMuon);
223 genupsilon->SetTrackingFlag(1);
17016a57 224 Double_t ratioupsilon; // Ratio with respect to the reaction cross-section for the muonic channel in the kinematics limit of the MUONCocktail
225 Double_t sigmaupsilon = 0.501e-6 * beautoniumshadowing; // section "6.7 Quarkonia Production" table 6.5 for pp times shadowing
226 Double_t brupsilon = 0.0248; // Branching Ratio for Upsilon
9538aedd 227 genupsilon->Init(); // Generating pT and Y parametrsation for the 4pi
228 ratioupsilon = sigmaupsilon * brupsilon * fNumberOfCollisions / sigmaReaction * genupsilon->GetRelativeArea(ptMin,ptMax,yMin,yMax,phiMin,phiMax);
17016a57 229 AliInfo(Form("Upsilon 1S production cross-section in pp with shadowing %5.3g barns",sigmaupsilon));
230 AliInfo(Form("Upsilon 1S production probability per collisions in acceptance via the muonic channel %5.3g",ratioupsilon));
9538aedd 231 genupsilon->SetPtRange(ptMin, ptMax);
232 genupsilon->SetYRange(yMin, yMax);
233 genupsilon->SetPhiRange(phiMin, phiMax);
234 genupsilon->Init(); // Generating pT and Y parametrsation in the desired kinematic range
235 AddGenerator(genupsilon,"Upsilon", ratioupsilon);
236 fTotalRate+=ratioupsilon;
84954c47 237
17016a57 238 // Generating UpsilonP Physics
239 // Using Ramona Vogt distribution form CERN Yelow report and Andreas MORSCH private communication
88e5db43 240 AliGenParam * genupsilonP = new AliGenParam(1, AliGenMUONlib::kUpsilonP, "Vogt", "UpsilonP");
241 genupsilonP->SetPtRange(0,100.);
242 genupsilonP->SetYRange(-8.,8);
243 genupsilonP->SetPhiRange(0.,360.);
244 genupsilonP->SetForceDecay(kDiMuon);
245 genupsilonP->SetTrackingFlag(1);
17016a57 246 Double_t ratioupsilonP; // Ratio with respect to the reaction cross-section for the muonic channel in the kinematics limit of the MUONCocktail
247 Double_t sigmaupsilonP = 0.246e-6 * beautoniumshadowing; // section "6.7 Quarkonia Production" table 6.5 for pp times shadowing
248 Double_t brupsilonP = 0.0131; // Branching Ratio for UpsilonP
88e5db43 249 genupsilonP->Init(); // Generating pT and Y parametrsation for the 4pi
250 ratioupsilonP = sigmaupsilonP * brupsilonP * fNumberOfCollisions / sigmaReaction * genupsilonP->GetRelativeArea(ptMin,ptMax,yMin,yMax,phiMin,phiMax);
17016a57 251 AliInfo(Form("Upsilon 2S production cross-section in pp with shadowing %5.3g barns",sigmaupsilonP));
252 AliInfo(Form("Upsilon 2S production probability per collisions in acceptance via the muonic channel %5.3g",ratioupsilonP));
88e5db43 253 genupsilonP->SetPtRange(ptMin, ptMax);
254 genupsilonP->SetYRange(yMin, yMax);
255 genupsilonP->SetPhiRange(phiMin, phiMax);
256 genupsilonP->Init(); // Generating pT and Y parametrsation in the desired kinematic range
257 AddGenerator(genupsilonP,"UpsilonP", ratioupsilonP);
258 fTotalRate+=ratioupsilonP;
259
17016a57 260 // Generating UpsilonPP Physics
261 // Using Ramona Vogt distribution form CERN Yelow report and Andreas MORSCH private communication
88e5db43 262 AliGenParam * genupsilonPP = new AliGenParam(1, AliGenMUONlib::kUpsilonPP, "Vogt", "UpsilonPP");
263 genupsilonPP->SetPtRange(0,100.);
264 genupsilonPP->SetYRange(-8.,8);
265 genupsilonPP->SetPhiRange(0.,360.);
266 genupsilonPP->SetForceDecay(kDiMuon);
267 genupsilonPP->SetTrackingFlag(1);
17016a57 268 Double_t ratioupsilonPP; // Ratio with respect to the reaction cross-section for the muonic channel in the kinematics limit of the MUONCocktail
269 Double_t sigmaupsilonPP = 0.100e-6 * beautoniumshadowing; // section "6.7 Quarkonia Production" table 6.5 for pp times shadowing
270 Double_t brupsilonPP = 0.0181; // Branching Ratio for UpsilonPP
88e5db43 271 genupsilonPP->Init(); // Generating pT and Y parametrsation for the 4pi
272 ratioupsilonPP = sigmaupsilonPP * brupsilonPP * fNumberOfCollisions / sigmaReaction * genupsilonPP->GetRelativeArea(ptMin,ptMax,yMin,yMax,phiMin,phiMax);
17016a57 273 AliInfo(Form("Upsilon 3S production cross-section in pp with shadowing %5.3g barns",sigmaupsilonPP));
274 AliInfo(Form("Upsilon 3S production probability per collisions in acceptance via the muonic channel %5.3g",ratioupsilonPP));
88e5db43 275 genupsilonPP->SetPtRange(ptMin, ptMax);
276 genupsilonPP->SetYRange(yMin, yMax);
277 genupsilonPP->SetPhiRange(phiMin, phiMax);
278 genupsilonPP->Init(); // Generating pT and Y parametrsation in the desired kinematic range
279 AddGenerator(genupsilonPP,"UpsilonPP", ratioupsilonPP);
280 fTotalRate+=ratioupsilonPP;
281
17016a57 282// Generating non-correlated Charm Physics
9538aedd 283 AliGenParam * gencharm = new AliGenParam(1, AliGenMUONlib::kCharm, "Vogt", "Charm");
284 gencharm->SetPtRange(0,100.);
285 gencharm->SetYRange(-8.,8);
286 gencharm->SetPhiRange(0.,360.);
287 gencharm->SetForceDecay(kSemiMuonic);
288 gencharm->SetTrackingFlag(1);
17016a57 289 Double_t ratiocharm; // Ratio with respect to the reaction cross-section for the muonic channel in the kinematics limit of the MUONCocktail
290 Double_t sigmacharm = 2. * 6.64e-3 * charmshadowing ; //
291 Double_t brcharm = 0.12; // Branching Ratio for Charm
9538aedd 292 gencharm->Init(); // Generating pT and Y parametrsation for the 4pi
17016a57 293 ratiocharm = sigmacharm * brcharm * fNumberOfCollisions / sigmaReaction * gencharm->GetRelativeArea(ptMin,ptMax,yMin,yMax,phiMin,phiMax);
294 AliInfo(Form("Charm production cross-section in pp with shadowing %5.3g barns",sigmacharm));
295 AliInfo(Form("Charm production probability per collisions in acceptance via the semi-muonic channel %5.3g",ratiocharm));
9538aedd 296 gencharm->SetPtRange(ptMin, ptMax);
297 gencharm->SetYRange(yMin, yMax);
298 gencharm->SetPhiRange(phiMin, phiMax);
299 gencharm->Init(); // Generating pT and Y parametrsation in the desired kinematic range
9538aedd 300 AddGenerator(gencharm,"Charm", ratiocharm);
301 fTotalRate+=ratiocharm;
84954c47 302
17016a57 303// Generating non-correlated Beauty Physics
304 AliGenParam * genbeauty = new AliGenParam(1, AliGenMUONlib::kBeauty, "Vogt", "Beauty");
9538aedd 305 genbeauty->SetPtRange(0,100.);
306 genbeauty->SetYRange(-8.,8);
307 genbeauty->SetPhiRange(0.,360.);
308 genbeauty->SetForceDecay(kSemiMuonic);
309 genbeauty->SetTrackingFlag(1);
17016a57 310 Double_t ratiobeauty; // Ratio with respect to the reaction cross-section for the muonic channel in the kinematics limit of the MUONCocktail
311 Double_t sigmabeauty = 2. * 0.210e-3 * beautyshadowing; //
312 Double_t brbeauty = 0.15; // Branching Ratio for Beauty
9538aedd 313 genbeauty->Init(); // Generating pT and Y parametrsation for the 4pi
314 ratiobeauty = sigmabeauty * brbeauty * fNumberOfCollisions / sigmaReaction *
315 genbeauty->GetRelativeArea(ptMin,ptMax,yMin,yMax,phiMin,phiMax);
17016a57 316 AliInfo(Form("Beauty production cross-section in pp with shadowing %5.3g barns",sigmabeauty));
317 AliInfo(Form("Beauty production probability per collisions in acceptance via the semi-muonic channel %5.3g",ratiobeauty));
9538aedd 318 genbeauty->SetPtRange(ptMin, ptMax);
319 genbeauty->SetYRange(yMin, yMax);
320 genbeauty->SetPhiRange(phiMin, phiMax);
321 genbeauty->Init(); // Generating pT and Y parametrisation in the desired kinematic range
9538aedd 322 AddGenerator(genbeauty,"Beauty", ratiobeauty);
323 fTotalRate+=ratiobeauty;
84954c47 324
17016a57 325 // Only if hadronic muons are included in the cocktail
326 if(fHadronicMuons) {
327 // Generating Pion Physics
328 // The scaling with Npart and Ncoll has been obtained to reproduced tha values presented by Valeri lors de presentatation
329 // a Clermont Ferrand http://pcrochet.home.cern.ch/pcrochet/files/valerie.pdf
330 // b range(fm) Ncoll Npart N_mu pT>0.4 GeV/c
331 // 0 - 3 1982 381 3.62
332 // 3 - 6 1388 297 3.07
333 // 6 - 9 674 177 1.76
334 // 9 - 12 188 71 0.655
335 // 12 - 16 15 10 0.086
336 // We found the hadronic muons scales quite well with the number of participants
337 AliGenParam * genpion = new AliGenParam(1, AliGenMUONlib::kPion, "Vogt", "Pion");
338 genpion->SetPtRange(0,100.);
339 genpion->SetYRange(-8.,8);
340 genpion->SetPhiRange(0.,360.);
341 genpion->SetForceDecay(kPiToMu);
342 genpion->SetTrackingFlag(1);
343 Double_t ratiopion; // Ratio with respect to the reaction cross-section for the muonic channel in the kinematics limit of the MUONCocktail
344 Double_t sigmapion = 1.80e-2; // Just for reproducing Valeries's data
345 Double_t brpion = 0.9999; // Branching Ratio for Pion
346 genpion->Init(); // Generating pT and Y parametrsation for the 4pi
347 ratiopion = sigmapion * brpion * (0.93*fNumberOfParticipants+0.07*fNumberOfCollisions) / sigmaReaction * genpion->GetRelativeArea(ptMin,ptMax,yMin,yMax,phiMin,phiMax);
348 AliInfo(Form("Pseudo-Pion production cross-section in pp with shadowing %5.3g barns",sigmapion));
349 AliInfo(Form("Pion production probability per collisions in acceptance via the muonic channel %5.3g",ratiopion));
350 genpion->SetPtRange(ptMin, ptMax);
351 genpion->SetYRange(yMin, yMax);
352 genpion->SetPhiRange(phiMin, phiMax);
353 genpion->Init(); // Generating pT and Y parametrsation in the desired kinematic range
354 AddGenerator(genpion,"Pion", ratiopion);
355 fTotalRate+=ratiopion;
356
357 // Generating Kaon Physics
358 AliGenParam * genkaon = new AliGenParam(1, AliGenMUONlib::kKaon, "Vogt", "Kaon");
359 genkaon->SetPtRange(0,100.);
360 genkaon->SetYRange(-8.,8);
361 genkaon->SetPhiRange(0.,360.);
362 genkaon->SetForceDecay(kKaToMu);
363 genkaon->SetTrackingFlag(1);
364 Double_t ratiokaon; // Ratio with respect to the reaction cross-section for the muonic channel in the kinematics limit of the MUONCocktail
365 Double_t sigmakaon = 2.40e-4; // Valerie presentation Clermont-16-jan-2004 and Alice-int-2002-06
366 Double_t brkaon = 0.6351 ; // Branching Ratio for Kaon
367 genkaon->Init(); // Generating pT and Y parametrsation for the 4pi
368 ratiokaon = sigmakaon * brkaon * (0.93*fNumberOfParticipants+0.07*fNumberOfCollisions)/ sigmaReaction * genkaon->GetRelativeArea(ptMin,ptMax,yMin,yMax,phiMin,phiMax);
369 AliInfo(Form("Pseudo-kaon production cross-section in pp with shadowing %5.3g barns",sigmakaon));
370 AliInfo(Form("Kaon production probability per collisions in acceptance via the muonic channel %5.3g",ratiokaon));
371 genkaon->SetPtRange(ptMin, ptMax);
372 genkaon->SetYRange(yMin, yMax);
373 genkaon->SetPhiRange(phiMin, phiMax);
374 genkaon->Init(); // Generating pT and Y parametrsation in the desired kinematic range
375 AddGenerator(genkaon,"Kaon", ratiokaon);
376 fTotalRate+=ratiokaon;
377 }
84954c47 378}
379
380//_________________________________________________________________________
381void AliGenMUONCocktail::Generate()
382{
383 //
384// Generate event
385 TIter next(fEntries);
386 AliGenCocktailEntry *entry = 0;
387 AliGenCocktailEntry *preventry = 0;
388 AliGenerator* gen = 0;
84954c47 389 TObjArray *partArray = gAlice->GetMCApp()->Particles();
390
17016a57 391// Generate the vertex position used by all generators
84954c47 392 if(fVertexSmear == kPerEvent) Vertex();
84954c47 393
17016a57 394 // Loop on primordialTrigger
395 Bool_t primordialTrigger = kFALSE;
9538aedd 396 while(!primordialTrigger) {
84954c47 397 //Reseting stack
398 AliRunLoader * runloader = gAlice->GetRunLoader();
399 if (runloader)
400 if (runloader->Stack())
401 runloader->Stack()->Reset();
84954c47 402 // Loop over generators and generate events
403 Int_t igen=0;
404 Int_t npart =0;
84954c47 405 while((entry = (AliGenCocktailEntry*)next())) {
406 gen = entry->Generator();
407 gen->SetVertex(fVertex.At(0), fVertex.At(1), fVertex.At(2));
408 if ( (npart = gRandom->Poisson(entry->Rate())) >0 ) {
409 igen++;
410 if (igen ==1) entry->SetFirst(0);
411 else entry->SetFirst((partArray->GetEntriesFast())+1);
412 gen->SetNumberParticles(npart);
413 gen->Generate();
414 entry->SetLast(partArray->GetEntriesFast());
415 preventry = entry;
416 }
417 }
418 next.Reset();
17016a57 419 // Tesitng primordial trigger : Muon pair in the MUON spectrometer acceptance and pTCut
84954c47 420 Int_t iPart;
421 fNGenerated++;
422 Int_t numberOfMuons=0;
423 // printf(">>>fNGenerated is %d\n",fNGenerated);
424 for(iPart=0; iPart<partArray->GetEntriesFast(); iPart++){
84954c47 425 if ( (TMath::Abs(gAlice->GetMCApp()->Particle(iPart)->GetPdgCode())==13) &&
426 (gAlice->GetMCApp()->Particle(iPart)->Theta()*180./TMath::Pi()>fMuonThetaMinCut) &&
427 (gAlice->GetMCApp()->Particle(iPart)->Theta()*180./TMath::Pi()<fMuonThetaMaxCut) &&
428 (gAlice->GetMCApp()->Particle(iPart)->Pt()>fMuonPtCut) ) {
429 gAlice->GetMCApp()->Particle(iPart)->SetProductionVertex(fVertex.At(0), fVertex.At(1), fVertex.At(2), 0.);
430 numberOfMuons++;
431 }
432 }
433 // printf(">>> Number of Muons is %d \n", numberOfMuons);
9538aedd 434 if (numberOfMuons >= fMuonMultiplicity ) primordialTrigger = kTRUE;
84954c47 435 }
84954c47 436 fNSucceded++;
84954c47 437}
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