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 SwitchOffHeavyQuarks(kFALSE);
82 fParticles = new TClonesArray("TParticle",10000);
84 // Set random number generator
85 AliHijingRndm::SetHijingRandom(GetRandom());
90 AliGenHijing::AliGenHijing(const AliGenHijing & hijing):
97 AliGenHijing::~AliGenHijing()
100 if ( fDsigmaDb) delete fDsigmaDb;
101 if ( fDnDb) delete fDnDb;
105 void AliGenHijing::Init()
110 fProjectile.Resize(8);
112 SetMC(new THijing(fEnergyCMS, fFrame, fProjectile, fTarget,
113 fAProjectile, fZProjectile, fATarget, fZTarget,
114 fMinImpactParam, fMaxImpactParam));
116 fHijing=(THijing*) fMCEvGen;
117 fHijing->SetIHPR2(2, fRadiation);
118 fHijing->SetIHPR2(3, fTrigger);
119 fHijing->SetIHPR2(6, fShadowing);
120 fHijing->SetIHPR2(12, fDecaysOff);
121 fHijing->SetIHPR2(21, fKeep);
122 fHijing->SetHIPR1(10, fPtMinJet);
123 fHijing->SetHIPR1(50, fSimpleJet);
128 // fQuench = 0: no quenching
129 // fQuench = 1: hijing default
130 // fQuench = 2: new LHC parameters for HIPR1(11) and HIPR1(14)
131 // fQuench = 3: new RHIC parameters for HIPR1(11) and HIPR1(14)
132 // fQuench = 4: new LHC parameters with log(e) dependence
133 // fQuench = 5: new RHIC parameters with log(e) dependence
134 fHijing->SetIHPR2(50, 0);
136 fHijing->SetIHPR2(4, 1);
138 fHijing->SetIHPR2(4, 0);
139 // New LHC parameters from Xin-Nian Wang
141 fHijing->SetHIPR1(14, 1.1);
142 fHijing->SetHIPR1(11, 3.7);
143 } else if (fQuench == 3) {
144 fHijing->SetHIPR1(14, 0.20);
145 fHijing->SetHIPR1(11, 2.5);
146 } else if (fQuench == 4) {
147 fHijing->SetIHPR2(50, 1);
148 fHijing->SetHIPR1(14, 4.*0.34);
149 fHijing->SetHIPR1(11, 3.7);
150 } else if (fQuench == 5) {
151 fHijing->SetIHPR2(50, 1);
152 fHijing->SetHIPR1(14, 0.34);
153 fHijing->SetHIPR1(11, 2.5);
159 if (fNoHeavyQuarks) {
160 fHijing->SetIHPR2(49, 1);
162 fHijing->SetIHPR2(49, 0);
171 fHijing->Initialize();
173 if (fEvaluate) EvaluateCrossSections();
177 void AliGenHijing::Generate()
179 // Generate one event
181 Float_t polar[3] = {0,0,0};
182 Float_t origin[3] = {0,0,0};
183 Float_t origin0[3] = {0,0,0};
187 // converts from mm/c to s
188 const Float_t kconv = 0.001/2.999792458e8;
192 Int_t j, kf, ks, imo;
198 for (j = 0;j < 3; j++) origin0[j] = fOrigin[j];
199 if(fVertexSmear == kPerEvent) {
201 for (j=0; j < 3; j++) origin0[j] = fVertex[j];
205 Float_t sign = (fRandomPz && (Rndm() < 0.5))? -1. : 1.;
208 // Generate one event
209 // --------------------------------------------------------------------------
210 fProjectileSpecn = 0;
211 fProjectileSpecp = 0;
214 // --------------------------------------------------------------------------
215 fHijing->GenerateEvent();
217 fHijing->ImportParticles(fParticles,"All");
218 if (fTrigger != kNoTrigger) {
219 if (!CheckTrigger()) continue;
224 Int_t np = fParticles->GetEntriesFast();
225 printf("\n **************************************************%d\n",np);
227 if (np == 0 ) continue;
229 Int_t* newPos = new Int_t[np];
230 Int_t* pSelected = new Int_t[np];
232 for (i = 0; i < np; i++) {
239 TParticle * iparticle = (TParticle *) fParticles->At(0);
240 fVertex[0] = origin0[0];
241 fVertex[1] = origin0[1];
242 fVertex[2] = origin0[2];
245 // First select parent particles
248 for (i = 0; i < np; i++) {
249 iparticle = (TParticle *) fParticles->At(i);
251 // Is this a parent particle ?
252 if (Stable(iparticle)) continue;
254 Bool_t selected = kTRUE;
255 Bool_t hasSelectedDaughters = kFALSE;
258 kf = iparticle->GetPdgCode();
259 ks = iparticle->GetStatusCode();
260 if (kf == 92) continue;
262 if (!fSelectAll) selected = KinematicSelection(iparticle, 0) &&
264 hasSelectedDaughters = DaughtersSelection(iparticle);
266 // Put particle on the stack if it is either selected or
267 // it is the mother of at least one seleted particle
269 if (selected || hasSelectedDaughters) {
273 } // particle loop parents
275 // Now select the final state particles
278 for (i = 0; i<np; i++) {
279 TParticle * iparticle = (TParticle *) fParticles->At(i);
280 // Is this a final state particle ?
281 if (!Stable(iparticle)) continue;
283 Bool_t selected = kTRUE;
284 kf = iparticle->GetPdgCode();
285 ks = iparticle->GetStatusCode();
287 // --------------------------------------------------------------------------
288 // Count spectator neutrons and protons
289 if(ks == 0 || ks == 1){
290 if(kf == kNeutron) fProjectileSpecn += 1;
291 if(kf == kProton) fProjectileSpecp += 1;
293 else if(ks == 10 || ks == 11){
294 if(kf == kNeutron) fTargetSpecn += 1;
295 if(kf == kProton) fTargetSpecp += 1;
297 // --------------------------------------------------------------------------
300 selected = KinematicSelection(iparticle,0)&&SelectFlavor(kf);
301 if (!fSpectators && selected) selected = (ks != 0 && ks != 1 && ks != 10
305 // Put particle on the stack if selected
311 } // particle loop final state
313 // Write particles to stack
315 for (i = 0; i<np; i++) {
316 TParticle * iparticle = (TParticle *) fParticles->At(i);
317 Bool_t hasMother = (iparticle->GetFirstMother() >=0);
318 Bool_t hasDaughter = (iparticle->GetFirstDaughter() >=0);
321 kf = iparticle->GetPdgCode();
322 ks = iparticle->GetStatusCode();
323 p[0] = iparticle->Px();
324 p[1] = iparticle->Py();
325 p[2] = iparticle->Pz() * sign;
326 origin[0] = origin0[0]+iparticle->Vx()/10;
327 origin[1] = origin0[1]+iparticle->Vy()/10;
328 origin[2] = origin0[2]+iparticle->Vz()/10;
329 tof = kconv*iparticle->T();
331 TParticle* mother = 0;
333 imo = iparticle->GetFirstMother();
334 mother = (TParticle *) fParticles->At(imo);
335 imo = (mother->GetPdgCode() != 92) ? newPos[imo] : -1;
337 Bool_t tFlag = (fTrackIt && !hasDaughter);
338 PushTrack(tFlag,imo,kf,p,origin,polar,
339 tof,kPNoProcess,nt, 1., ks);
347 printf("\n I've put %i particles on the stack \n",nc);
350 if (jev >= fNpart || fNpart == -1) {
351 fKineBias = Float_t(fNpart)/Float_t(fTrials);
352 printf("\n Trials: %i %i %i\n",fTrials, fNpart, jev);
358 SetHighWaterMark(nt);
361 void AliGenHijing::KeepFullEvent()
366 void AliGenHijing::EvaluateCrossSections()
368 // Glauber Calculation of geometrical x-section
370 Float_t xTot = 0.; // barn
371 Float_t xTotHard = 0.; // barn
372 Float_t xPart = 0.; // barn
373 Float_t xPartHard = 0.; // barn
374 Float_t sigmaHard = 0.1; // mbarn
376 Float_t bMax = fHijing->GetHIPR1(34)+fHijing->GetHIPR1(35);
377 const Float_t kdib = 0.2;
378 Int_t kMax = Int_t((bMax-bMin)/kdib)+1;
381 printf("\n Projectile Radius (fm): %f \n",fHijing->GetHIPR1(34));
382 printf("\n Target Radius (fm): %f \n",fHijing->GetHIPR1(35));
384 Float_t oldvalue= 0.;
386 Float_t* b = new Float_t[kMax];
387 Float_t* si1 = new Float_t[kMax];
388 Float_t* si2 = new Float_t[kMax];
390 for (i = 0; i < kMax; i++)
392 Float_t xb = bMin+i*kdib;
394 ov=fHijing->Profile(xb);
395 Float_t gb = 2.*0.01*fHijing->GetHIPR1(40)*kdib*xb*(1.-TMath::Exp(-fHijing->GetHINT1(12)*ov));
396 Float_t gbh = 2.*0.01*fHijing->GetHIPR1(40)*kdib*xb*sigmaHard*ov;
399 printf("profile %f %f %f\n", xb, ov, fHijing->GetHINT1(12));
401 if (xb > fMinImpactParam && xb < fMaxImpactParam)
407 if(oldvalue) if ((xTot-oldvalue)/oldvalue<0.0001) break;
409 printf("\n Total cross section (barn): %d %f %f \n",i, xb, xTot);
410 printf("\n Hard cross section (barn): %d %f %f \n\n",i, xb, xTotHard);
418 printf("\n Total cross section (barn): %f \n",xTot);
419 printf("\n Hard cross section (barn): %f \n \n",xTotHard);
420 printf("\n Partial cross section (barn): %f %f \n",xPart, xPart/xTot*100.);
421 printf("\n Partial hard cross section (barn): %f %f \n",xPartHard, xPartHard/xTotHard*100.);
423 // Store result as a graph
428 fDsigmaDb = new TGraph(i, b, si1);
429 fDnDb = new TGraph(i, b, si2);
432 Bool_t AliGenHijing::DaughtersSelection(TParticle* iparticle)
435 // Looks recursively if one of the daughters has been selected
437 // printf("\n Consider daughters %d:",iparticle->GetPdgCode());
441 Bool_t hasDaughters = (iparticle->GetFirstDaughter() >=0);
442 Bool_t selected = kFALSE;
444 imin = iparticle->GetFirstDaughter();
445 imax = iparticle->GetLastDaughter();
446 for (i = imin; i <= imax; i++){
447 TParticle * jparticle = (TParticle *) fParticles->At(i);
448 Int_t ip = jparticle->GetPdgCode();
449 if (KinematicSelection(jparticle,0)&&SelectFlavor(ip)) {
450 selected=kTRUE; break;
452 if (DaughtersSelection(jparticle)) {selected=kTRUE; break; }
461 Bool_t AliGenHijing::SelectFlavor(Int_t pid)
463 // Select flavor of particle
465 // 4: charm and beauty
472 Int_t ifl = TMath::Abs(pid/100);
473 if (ifl > 10) ifl/=10;
474 res = (fFlavor == ifl);
477 // This part if gamma writing is inhibited
479 res = res && (pid != kGamma && pid != kPi0);
484 Bool_t AliGenHijing::Stable(TParticle* particle) const
486 // Return true for a stable particle
489 if (particle->GetFirstDaughter() < 0 )
499 void AliGenHijing::MakeHeader()
501 // Builds the event header, to be called after each event
502 AliGenEventHeader* header = new AliGenHijingEventHeader("Hijing");
503 ((AliGenHijingEventHeader*) header)->SetNProduced(fHijing->GetNATT());
504 ((AliGenHijingEventHeader*) header)->SetImpactParameter(fHijing->GetHINT1(19));
505 ((AliGenHijingEventHeader*) header)->SetTotalEnergy(fHijing->GetEATT());
506 ((AliGenHijingEventHeader*) header)->SetHardScatters(fHijing->GetJATT());
507 ((AliGenHijingEventHeader*) header)->SetParticipants(fHijing->GetNP(), fHijing->GetNT());
508 ((AliGenHijingEventHeader*) header)->SetCollisions(fHijing->GetN0(),
512 ((AliGenHijingEventHeader*) header)->SetSpectators(fProjectileSpecn, fProjectileSpecp,
513 fTargetSpecn,fTargetSpecp);
515 // 4-momentum vectors of the triggered jets.
517 // Before final state gluon radiation.
518 TLorentzVector* jet1 = new TLorentzVector(fHijing->GetHINT1(21),
519 fHijing->GetHINT1(22),
520 fHijing->GetHINT1(23),
521 fHijing->GetHINT1(24));
523 TLorentzVector* jet2 = new TLorentzVector(fHijing->GetHINT1(31),
524 fHijing->GetHINT1(32),
525 fHijing->GetHINT1(33),
526 fHijing->GetHINT1(34));
527 // After final state gluon radiation.
528 TLorentzVector* jet3 = new TLorentzVector(fHijing->GetHINT1(26),
529 fHijing->GetHINT1(27),
530 fHijing->GetHINT1(28),
531 fHijing->GetHINT1(29));
533 TLorentzVector* jet4 = new TLorentzVector(fHijing->GetHINT1(36),
534 fHijing->GetHINT1(37),
535 fHijing->GetHINT1(38),
536 fHijing->GetHINT1(39));
537 ((AliGenHijingEventHeader*) header)->SetJets(jet1, jet2, jet3, jet4);
538 // Bookkeeping for kinematic bias
539 ((AliGenHijingEventHeader*) header)->SetTrials(fTrials);
541 header->SetPrimaryVertex(fVertex);
542 if (gAlice) gAlice->SetGenEventHeader(header);
543 fCollisionGeometry = (AliGenHijingEventHeader*) header;
546 Bool_t AliGenHijing::CheckTrigger()
548 // Check the kinematic trigger condition
550 Bool_t triggered = kFALSE;
556 TLorentzVector* jet1 = new TLorentzVector(fHijing->GetHINT1(26),
557 fHijing->GetHINT1(27),
558 fHijing->GetHINT1(28),
559 fHijing->GetHINT1(29));
561 TLorentzVector* jet2 = new TLorentzVector(fHijing->GetHINT1(36),
562 fHijing->GetHINT1(37),
563 fHijing->GetHINT1(38),
564 fHijing->GetHINT1(39));
565 Double_t eta1 = jet1->Eta();
566 Double_t eta2 = jet2->Eta();
567 Double_t phi1 = jet1->Phi();
568 Double_t phi2 = jet2->Phi();
569 // printf("\n Trigger: %f %f %f %f",
570 // fEtaMinJet, fEtaMaxJet, fPhiMinJet, fPhiMaxJet);
572 (eta1 < fEtaMaxJet && eta1 > fEtaMinJet &&
573 phi1 < fPhiMaxJet && phi1 > fPhiMinJet)
575 (eta2 < fEtaMaxJet && eta2 > fEtaMinJet &&
576 phi2 < fPhiMaxJet && phi2 > fPhiMinJet)
579 } else if (fTrigger == 2) {
582 Int_t np = fParticles->GetEntriesFast();
583 for (Int_t i = 0; i < np; i++) {
584 TParticle* part = (TParticle*) fParticles->At(i);
585 Int_t kf = part->GetPdgCode();
586 Int_t ks = part->GetStatusCode();
587 if (kf == 22 && ks == 40) {
588 Float_t phi = part->Phi();
589 Float_t eta = part->Eta();
590 if (eta < fEtaMaxJet &&
596 } // check phi,eta within limits
604 void AliGenHijing::Copy(TObject &) const
606 Fatal("Copy","Not implemented!\n");
609 AliGenHijing& AliGenHijing::operator=(const AliGenHijing& rhs)