1 /**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
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 **************************************************************************/
18 // Generator using HIJING as an external generator
19 // The main HIJING options are accessable for the user through this interface.
20 // Uses the THijing implementation of TGenerator.
22 // Andreas Morsch (andreas.morsch@cern.ch)
27 #include <TLorentzVector.h>
29 #include <TParticle.h>
31 #include "AliGenHijing.h"
32 #include "AliGenHijingEventHeader.h"
34 #include "AliHijingRndm.h"
36 ClassImp(AliGenHijing)
38 AliGenHijing::AliGenHijing()
46 AliHijingRndm::SetHijingRandom(GetRandom());
49 AliGenHijing::AliGenHijing(Int_t npart)
52 // Default PbPb collisions at 5. 5 TeV
55 fTitle= "Particle Generator using HIJING";
58 SetImpactParameterRange();
80 fParticles = new TClonesArray("TParticle",10000);
82 // Set random number generator
83 AliHijingRndm::SetHijingRandom(GetRandom());
88 AliGenHijing::AliGenHijing(const AliGenHijing & hijing):
95 AliGenHijing::~AliGenHijing()
98 if ( fDsigmaDb) delete fDsigmaDb;
99 if ( fDnDb) delete fDnDb;
103 void AliGenHijing::Init()
108 fProjectile.Resize(8);
110 SetMC(new THijing(fEnergyCMS, fFrame, fProjectile, fTarget,
111 fAProjectile, fZProjectile, fATarget, fZTarget,
112 fMinImpactParam, fMaxImpactParam));
114 fHijing=(THijing*) fMCEvGen;
115 fHijing->SetIHPR2(2, fRadiation);
116 fHijing->SetIHPR2(3, fTrigger);
117 fHijing->SetIHPR2(6, fShadowing);
118 fHijing->SetIHPR2(12, fDecaysOff);
119 fHijing->SetIHPR2(21, fKeep);
120 fHijing->SetHIPR1(10, fPtMinJet);
121 fHijing->SetHIPR1(50, fSimpleJet);
126 // fQuench = 0: no quenching
127 // fQuench = 1: hijing default
128 // fQuench = 2: new LHC parameters for HIPR1(11) and HIPR1(14)
129 // fQuench = 3: new RHIC parameters for HIPR1(11) and HIPR1(14)
130 // fQuench = 4: new LHC parameters with log(e) dependence
131 // fQuench = 5: new RHIC parameters with log(e) dependence
132 fHijing->SetIHPR2(50, 0);
134 fHijing->SetIHPR2(4, 1);
136 fHijing->SetIHPR2(4, 0);
137 // New LHC parameters from Xin-Nian Wang
139 fHijing->SetHIPR1(14, 1.1);
140 fHijing->SetHIPR1(11, 3.7);
141 } else if (fQuench == 3) {
142 fHijing->SetHIPR1(14, 0.20);
143 fHijing->SetHIPR1(11, 2.5);
144 } else if (fQuench == 4) {
145 fHijing->SetIHPR2(50, 1);
146 fHijing->SetHIPR1(14, 4.*0.34);
147 fHijing->SetHIPR1(11, 3.7);
148 } else if (fQuench == 5) {
149 fHijing->SetIHPR2(50, 1);
150 fHijing->SetHIPR1(14, 0.34);
151 fHijing->SetHIPR1(11, 2.5);
160 fHijing->Initialize();
162 if (fEvaluate) EvaluateCrossSections();
166 void AliGenHijing::Generate()
168 // Generate one event
170 Float_t polar[3] = {0,0,0};
171 Float_t origin[3] = {0,0,0};
172 Float_t origin0[3] = {0,0,0};
176 // converts from mm/c to s
177 const Float_t kconv = 0.001/2.999792458e8;
181 Int_t j, kf, ks, imo;
187 for (j = 0;j < 3; j++) origin0[j] = fOrigin[j];
188 if(fVertexSmear == kPerEvent) {
190 for (j=0; j < 3; j++) origin0[j] = fVertex[j];
195 // Generate one event
196 // --------------------------------------------------------------------------
197 fProjectileSpecn = 0;
198 fProjectileSpecp = 0;
201 // --------------------------------------------------------------------------
202 fHijing->GenerateEvent();
204 fHijing->ImportParticles(fParticles,"All");
205 if (fTrigger != kNoTrigger) {
206 if (!CheckTrigger()) continue;
211 Int_t np = fParticles->GetEntriesFast();
212 printf("\n **************************************************%d\n",np);
214 if (np == 0 ) continue;
216 Int_t* newPos = new Int_t[np];
217 Int_t* pSelected = new Int_t[np];
219 for (i = 0; i < np; i++) {
226 TParticle * iparticle = (TParticle *) fParticles->At(0);
227 fVertex[0] = origin0[0];
228 fVertex[1] = origin0[1];
229 fVertex[2] = origin0[2];
232 // First select parent particles
235 for (i = 0; i < np; i++) {
236 iparticle = (TParticle *) fParticles->At(i);
238 // Is this a parent particle ?
239 if (Stable(iparticle)) continue;
241 Bool_t selected = kTRUE;
242 Bool_t hasSelectedDaughters = kFALSE;
245 kf = iparticle->GetPdgCode();
246 ks = iparticle->GetStatusCode();
247 if (kf == 92) continue;
249 if (!fSelectAll) selected = KinematicSelection(iparticle, 0) &&
251 hasSelectedDaughters = DaughtersSelection(iparticle);
253 // Put particle on the stack if it is either selected or
254 // it is the mother of at least one seleted particle
256 if (selected || hasSelectedDaughters) {
260 } // particle loop parents
262 // Now select the final state particles
265 for (i = 0; i<np; i++) {
266 TParticle * iparticle = (TParticle *) fParticles->At(i);
267 // Is this a final state particle ?
268 if (!Stable(iparticle)) continue;
270 Bool_t selected = kTRUE;
271 kf = iparticle->GetPdgCode();
272 ks = iparticle->GetStatusCode();
274 // --------------------------------------------------------------------------
275 // Count spectator neutrons and protons
276 if(ks == 0 || ks == 1){
277 if(kf == kNeutron) fProjectileSpecn += 1;
278 if(kf == kProton) fProjectileSpecp += 1;
280 else if(ks == 10 || ks == 11){
281 if(kf == kNeutron) fTargetSpecn += 1;
282 if(kf == kProton) fTargetSpecp += 1;
284 // --------------------------------------------------------------------------
287 selected = KinematicSelection(iparticle,0)&&SelectFlavor(kf);
288 if (!fSpectators && selected) selected = (ks != 0 && ks != 1 && ks != 10
292 // Put particle on the stack if selected
298 } // particle loop final state
300 // Write particles to stack
302 for (i = 0; i<np; i++) {
303 TParticle * iparticle = (TParticle *) fParticles->At(i);
304 Bool_t hasMother = (iparticle->GetFirstMother() >=0);
305 Bool_t hasDaughter = (iparticle->GetFirstDaughter() >=0);
308 kf = iparticle->GetPdgCode();
309 ks = iparticle->GetStatusCode();
310 p[0] = iparticle->Px();
311 p[1] = iparticle->Py();
312 p[2] = iparticle->Pz();
313 origin[0] = origin0[0]+iparticle->Vx()/10;
314 origin[1] = origin0[1]+iparticle->Vy()/10;
315 origin[2] = origin0[2]+iparticle->Vz()/10;
316 tof = kconv*iparticle->T();
318 TParticle* mother = 0;
320 imo = iparticle->GetFirstMother();
321 mother = (TParticle *) fParticles->At(imo);
322 imo = (mother->GetPdgCode() != 92) ? imo = newPos[imo] : -1;
324 Bool_t tFlag = (fTrackIt && !hasDaughter);
325 PushTrack(tFlag,imo,kf,p,origin,polar,
326 tof,kPNoProcess,nt, 1., ks);
334 printf("\n I've put %i particles on the stack \n",nc);
337 if (jev >= fNpart || fNpart == -1) {
338 fKineBias = Float_t(fNpart)/Float_t(fTrials);
339 printf("\n Trials: %i %i %i\n",fTrials, fNpart, jev);
345 SetHighWaterMark(nt);
348 void AliGenHijing::KeepFullEvent()
353 void AliGenHijing::EvaluateCrossSections()
355 // Glauber Calculation of geometrical x-section
357 Float_t xTot = 0.; // barn
358 Float_t xTotHard = 0.; // barn
359 Float_t xPart = 0.; // barn
360 Float_t xPartHard = 0.; // barn
361 Float_t sigmaHard = 0.1; // mbarn
363 Float_t bMax = fHijing->GetHIPR1(34)+fHijing->GetHIPR1(35);
364 const Float_t kdib = 0.2;
365 Int_t kMax = Int_t((bMax-bMin)/kdib)+1;
368 printf("\n Projectile Radius (fm): %f \n",fHijing->GetHIPR1(34));
369 printf("\n Target Radius (fm): %f \n",fHijing->GetHIPR1(35));
371 Float_t oldvalue= 0.;
373 Float_t* b = new Float_t[kMax];
374 Float_t* si1 = new Float_t[kMax];
375 Float_t* si2 = new Float_t[kMax];
377 for (i = 0; i < kMax; i++)
379 Float_t xb = bMin+i*kdib;
381 ov=fHijing->Profile(xb);
382 Float_t gb = 2.*0.01*fHijing->GetHIPR1(40)*kdib*xb*(1.-TMath::Exp(-fHijing->GetHINT1(12)*ov));
383 Float_t gbh = 2.*0.01*fHijing->GetHIPR1(40)*kdib*xb*sigmaHard*ov;
386 printf("profile %f %f %f\n", xb, ov, fHijing->GetHINT1(12));
388 if (xb > fMinImpactParam && xb < fMaxImpactParam)
394 if(oldvalue) if ((xTot-oldvalue)/oldvalue<0.0001) break;
396 printf("\n Total cross section (barn): %d %f %f \n",i, xb, xTot);
397 printf("\n Hard cross section (barn): %d %f %f \n\n",i, xb, xTotHard);
405 printf("\n Total cross section (barn): %f \n",xTot);
406 printf("\n Hard cross section (barn): %f \n \n",xTotHard);
407 printf("\n Partial cross section (barn): %f %f \n",xPart, xPart/xTot*100.);
408 printf("\n Partial hard cross section (barn): %f %f \n",xPartHard, xPartHard/xTotHard*100.);
410 // Store result as a graph
415 fDsigmaDb = new TGraph(i, b, si1);
416 fDnDb = new TGraph(i, b, si2);
419 Bool_t AliGenHijing::DaughtersSelection(TParticle* iparticle)
422 // Looks recursively if one of the daughters has been selected
424 // printf("\n Consider daughters %d:",iparticle->GetPdgCode());
428 Bool_t hasDaughters = (iparticle->GetFirstDaughter() >=0);
429 Bool_t selected = kFALSE;
431 imin = iparticle->GetFirstDaughter();
432 imax = iparticle->GetLastDaughter();
433 for (i = imin; i <= imax; i++){
434 TParticle * jparticle = (TParticle *) fParticles->At(i);
435 Int_t ip = jparticle->GetPdgCode();
436 if (KinematicSelection(jparticle,0)&&SelectFlavor(ip)) {
437 selected=kTRUE; break;
439 if (DaughtersSelection(jparticle)) {selected=kTRUE; break; }
448 Bool_t AliGenHijing::SelectFlavor(Int_t pid)
450 // Select flavor of particle
452 // 4: charm and beauty
459 Int_t ifl = TMath::Abs(pid/100);
460 if (ifl > 10) ifl/=10;
461 res = (fFlavor == ifl);
464 // This part if gamma writing is inhibited
466 res = res && (pid != kGamma && pid != kPi0);
471 Bool_t AliGenHijing::Stable(TParticle* particle) const
473 // Return true for a stable particle
476 if (particle->GetFirstDaughter() < 0 )
486 void AliGenHijing::MakeHeader()
488 // Builds the event header, to be called after each event
489 AliGenEventHeader* header = new AliGenHijingEventHeader("Hijing");
490 ((AliGenHijingEventHeader*) header)->SetNProduced(fHijing->GetNATT());
491 ((AliGenHijingEventHeader*) header)->SetImpactParameter(fHijing->GetHINT1(19));
492 ((AliGenHijingEventHeader*) header)->SetTotalEnergy(fHijing->GetEATT());
493 ((AliGenHijingEventHeader*) header)->SetHardScatters(fHijing->GetJATT());
494 ((AliGenHijingEventHeader*) header)->SetParticipants(fHijing->GetNP(), fHijing->GetNT());
495 ((AliGenHijingEventHeader*) header)->SetCollisions(fHijing->GetN0(),
499 ((AliGenHijingEventHeader*) header)->SetSpectators(fProjectileSpecn, fProjectileSpecp,
500 fTargetSpecn,fTargetSpecp);
502 // 4-momentum vectors of the triggered jets.
504 // Before final state gluon radiation.
505 TLorentzVector* jet1 = new TLorentzVector(fHijing->GetHINT1(21),
506 fHijing->GetHINT1(22),
507 fHijing->GetHINT1(23),
508 fHijing->GetHINT1(24));
510 TLorentzVector* jet2 = new TLorentzVector(fHijing->GetHINT1(31),
511 fHijing->GetHINT1(32),
512 fHijing->GetHINT1(33),
513 fHijing->GetHINT1(34));
514 // After final state gluon radiation.
515 TLorentzVector* jet3 = new TLorentzVector(fHijing->GetHINT1(26),
516 fHijing->GetHINT1(27),
517 fHijing->GetHINT1(28),
518 fHijing->GetHINT1(29));
520 TLorentzVector* jet4 = new TLorentzVector(fHijing->GetHINT1(36),
521 fHijing->GetHINT1(37),
522 fHijing->GetHINT1(38),
523 fHijing->GetHINT1(39));
524 ((AliGenHijingEventHeader*) header)->SetJets(jet1, jet2, jet3, jet4);
525 // Bookkeeping for kinematic bias
526 ((AliGenHijingEventHeader*) header)->SetTrials(fTrials);
528 header->SetPrimaryVertex(fVertex);
529 if (gAlice) gAlice->SetGenEventHeader(header);
530 fCollisionGeometry = (AliGenHijingEventHeader*) header;
533 Bool_t AliGenHijing::CheckTrigger()
535 // Check the kinematic trigger condition
537 Bool_t triggered = kFALSE;
543 TLorentzVector* jet1 = new TLorentzVector(fHijing->GetHINT1(26),
544 fHijing->GetHINT1(27),
545 fHijing->GetHINT1(28),
546 fHijing->GetHINT1(29));
548 TLorentzVector* jet2 = new TLorentzVector(fHijing->GetHINT1(36),
549 fHijing->GetHINT1(37),
550 fHijing->GetHINT1(38),
551 fHijing->GetHINT1(39));
552 Double_t eta1 = jet1->Eta();
553 Double_t eta2 = jet2->Eta();
554 Double_t phi1 = jet1->Phi();
555 Double_t phi2 = jet2->Phi();
556 // printf("\n Trigger: %f %f %f %f",
557 // fEtaMinJet, fEtaMaxJet, fPhiMinJet, fPhiMaxJet);
559 (eta1 < fEtaMaxJet && eta1 > fEtaMinJet &&
560 phi1 < fPhiMaxJet && phi1 > fPhiMinJet)
562 (eta2 < fEtaMaxJet && eta2 > fEtaMinJet &&
563 phi2 < fPhiMaxJet && phi2 > fPhiMinJet)
566 } else if (fTrigger == 2) {
569 Int_t np = fParticles->GetEntriesFast();
570 for (Int_t i = 0; i < np; i++) {
571 TParticle* part = (TParticle*) fParticles->At(i);
572 Int_t kf = part->GetPdgCode();
573 Int_t ks = part->GetStatusCode();
574 if (kf == 22 && ks == 40) {
575 Float_t phi = part->Phi();
576 Float_t eta = part->Eta();
577 if (eta < fEtaMaxJet &&
583 } // check phi,eta within limits
591 void AliGenHijing::Copy(TObject &) const
593 Fatal("Copy","Not implemented!\n");
596 AliGenHijing& AliGenHijing::operator=(const AliGenHijing& rhs)