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@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();
81 fParticles = new TClonesArray("TParticle",10000);
83 // Set random number generator
84 AliHijingRndm::SetHijingRandom(GetRandom());
89 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*) fgMCEvGen;
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};
173 Float_t p[3], random[6];
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) {
191 while(TMath::Abs(dv[2]) > fCutVertexZ*fOsigma[2]) {
193 for (j=0; j < 3; j++) {
194 dv[j] = fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
195 TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
198 for (j=0; j < 3; j++) origin0[j] += dv[j];
199 } else if (fVertexSmear == kPerTrack) {
200 // fHijing->SetMSTP(151,0);
201 for (j = 0; j < 3; j++) {
202 // fHijing->SetPARP(151+j, fOsigma[j]*10.);
207 // Generate one event
208 // --------------------------------------------------------------------------
211 // --------------------------------------------------------------------------
212 fHijing->GenerateEvent();
214 fHijing->ImportParticles(fParticles,"All");
215 if (fTrigger != kNoTrigger) {
216 if (!CheckTrigger()) continue;
221 Int_t np = fParticles->GetEntriesFast();
222 printf("\n **************************************************%d\n",np);
224 if (np == 0 ) continue;
226 Int_t* newPos = new Int_t[np];
227 Int_t* pSelected = new Int_t[np];
229 for (i = 0; i < np; i++) {
236 TParticle * iparticle = (TParticle *) fParticles->At(0);
237 fEventVertex[0] = origin0[0];
238 fEventVertex[1] = origin0[1];
239 fEventVertex[2] = origin0[2];
242 // First select parent particles
245 for (i = 0; i < np; i++) {
246 iparticle = (TParticle *) fParticles->At(i);
248 // Is this a parent particle ?
249 if (Stable(iparticle)) continue;
251 Bool_t selected = kTRUE;
252 Bool_t hasSelectedDaughters = kFALSE;
255 kf = iparticle->GetPdgCode();
256 ks = iparticle->GetStatusCode();
257 if (kf == 92) continue;
259 if (!fSelectAll) selected = KinematicSelection(iparticle, 0) &&
261 hasSelectedDaughters = DaughtersSelection(iparticle);
263 // Put particle on the stack if it is either selected or
264 // it is the mother of at least one seleted particle
266 if (selected || hasSelectedDaughters) {
270 } // particle loop parents
272 // Now select the final state particles
275 for (i = 0; i<np; i++) {
276 TParticle * iparticle = (TParticle *) fParticles->At(i);
277 // Is this a final state particle ?
278 if (!Stable(iparticle)) continue;
280 Bool_t selected = kTRUE;
281 kf = iparticle->GetPdgCode();
282 ks = iparticle->GetStatusCode();
284 // --------------------------------------------------------------------------
285 // Count spectator neutrons and protons
286 if(ks == 0 || ks == 1 || ks == 10 || ks == 11){
287 if(kf == kNeutron) fSpecn += 1;
288 if(kf == kProton) fSpecp += 1;
290 // --------------------------------------------------------------------------
293 selected = KinematicSelection(iparticle,0)&&SelectFlavor(kf);
294 if (!fSpectators && selected) selected = (ks != 0 && ks != 1 && ks != 10
298 // Put particle on the stack if selected
304 } // particle loop final state
306 // Write particles to stack
308 for (i = 0; i<np; i++) {
309 TParticle * iparticle = (TParticle *) fParticles->At(i);
310 Bool_t hasMother = (iparticle->GetFirstMother() >=0);
311 Bool_t hasDaughter = (iparticle->GetFirstDaughter() >=0);
314 kf = iparticle->GetPdgCode();
315 ks = iparticle->GetStatusCode();
316 p[0] = iparticle->Px();
317 p[1] = iparticle->Py();
318 p[2] = iparticle->Pz();
319 origin[0] = origin0[0]+iparticle->Vx()/10;
320 origin[1] = origin0[1]+iparticle->Vy()/10;
321 origin[2] = origin0[2]+iparticle->Vz()/10;
322 tof = kconv*iparticle->T();
324 TParticle* mother = 0;
326 imo = iparticle->GetFirstMother();
327 mother = (TParticle *) fParticles->At(imo);
328 imo = (mother->GetPdgCode() != 92) ? imo = newPos[imo] : -1;
330 Bool_t tFlag = (fTrackIt && !hasDaughter);
331 SetTrack(tFlag,imo,kf,p,origin,polar,
332 tof,kPNoProcess,nt, 1., ks);
340 printf("\n I've put %i particles on the stack \n",nc);
343 if (jev >= fNpart || fNpart == -1) {
344 fKineBias = Float_t(fNpart)/Float_t(fTrials);
345 printf("\n Trials: %i %i %i\n",fTrials, fNpart, jev);
351 SetHighWaterMark(nt);
354 void AliGenHijing::KeepFullEvent()
359 void AliGenHijing::EvaluateCrossSections()
361 // Glauber Calculation of geometrical x-section
363 Float_t xTot = 0.; // barn
364 Float_t xTotHard = 0.; // barn
365 Float_t xPart = 0.; // barn
366 Float_t xPartHard = 0.; // barn
367 Float_t sigmaHard = 0.1; // mbarn
369 Float_t bMax = fHijing->GetHIPR1(34)+fHijing->GetHIPR1(35);
370 const Float_t kdib = 0.2;
371 Int_t kMax = Int_t((bMax-bMin)/kdib)+1;
374 printf("\n Projectile Radius (fm): %f \n",fHijing->GetHIPR1(34));
375 printf("\n Target Radius (fm): %f \n",fHijing->GetHIPR1(35));
377 Float_t oldvalue= 0.;
379 Float_t* b = new Float_t[kMax];
380 Float_t* si1 = new Float_t[kMax];
381 Float_t* si2 = new Float_t[kMax];
383 for (i = 0; i < kMax; i++)
385 Float_t xb = bMin+i*kdib;
387 ov=fHijing->Profile(xb);
388 Float_t gb = 2.*0.01*fHijing->GetHIPR1(40)*kdib*xb*(1.-TMath::Exp(-fHijing->GetHINT1(12)*ov));
389 Float_t gbh = 2.*0.01*fHijing->GetHIPR1(40)*kdib*xb*sigmaHard*ov;
392 printf("profile %f %f %f\n", xb, ov, fHijing->GetHINT1(12));
394 if (xb > fMinImpactParam && xb < fMaxImpactParam)
400 if(oldvalue) if ((xTot-oldvalue)/oldvalue<0.0001) break;
402 printf("\n Total cross section (barn): %d %f %f \n",i, xb, xTot);
403 printf("\n Hard cross section (barn): %d %f %f \n\n",i, xb, xTotHard);
411 printf("\n Total cross section (barn): %f \n",xTot);
412 printf("\n Hard cross section (barn): %f \n \n",xTotHard);
413 printf("\n Partial cross section (barn): %f %f \n",xPart, xPart/xTot*100.);
414 printf("\n Partial hard cross section (barn): %f %f \n",xPartHard, xPartHard/xTotHard*100.);
416 // Store result as a graph
421 fDsigmaDb = new TGraph(i, b, si1);
422 fDnDb = new TGraph(i, b, si2);
425 Bool_t AliGenHijing::DaughtersSelection(TParticle* iparticle)
428 // Looks recursively if one of the daughters has been selected
430 // printf("\n Consider daughters %d:",iparticle->GetPdgCode());
434 Bool_t hasDaughters = (iparticle->GetFirstDaughter() >=0);
435 Bool_t selected = kFALSE;
437 imin = iparticle->GetFirstDaughter();
438 imax = iparticle->GetLastDaughter();
439 for (i = imin; i <= imax; i++){
440 TParticle * jparticle = (TParticle *) fParticles->At(i);
441 Int_t ip = jparticle->GetPdgCode();
442 if (KinematicSelection(jparticle,0)&&SelectFlavor(ip)) {
443 selected=kTRUE; break;
445 if (DaughtersSelection(jparticle)) {selected=kTRUE; break; }
454 Bool_t AliGenHijing::SelectFlavor(Int_t pid)
456 // Select flavor of particle
458 // 4: charm and beauty
465 Int_t ifl = TMath::Abs(pid/100);
466 if (ifl > 10) ifl/=10;
467 res = (fFlavor == ifl);
470 // This part if gamma writing is inhibited
472 res = res && (pid != kGamma && pid != kPi0);
477 Bool_t AliGenHijing::Stable(TParticle* particle)
479 // Return true for a stable particle
482 if (particle->GetFirstDaughter() < 0 )
492 void AliGenHijing::MakeHeader()
494 // Builds the event header, to be called after each event
495 AliGenEventHeader* header = new AliGenHijingEventHeader("Hijing");
496 ((AliGenHijingEventHeader*) header)->SetNProduced(fHijing->GetNATT());
497 ((AliGenHijingEventHeader*) header)->SetImpactParameter(fHijing->GetHINT1(19));
498 ((AliGenHijingEventHeader*) header)->SetTotalEnergy(fHijing->GetEATT());
499 ((AliGenHijingEventHeader*) header)->SetHardScatters(fHijing->GetJATT());
500 ((AliGenHijingEventHeader*) header)->SetParticipants(fHijing->GetNP(), fHijing->GetNT());
501 ((AliGenHijingEventHeader*) header)->SetCollisions(fHijing->GetN0(),
505 ((AliGenHijingEventHeader*) header)->SetSpectators(fSpecn, fSpecp);
507 // 4-momentum vectors of the triggered jets.
509 // Before final state gluon radiation.
510 TLorentzVector* jet1 = new TLorentzVector(fHijing->GetHINT1(21),
511 fHijing->GetHINT1(22),
512 fHijing->GetHINT1(23),
513 fHijing->GetHINT1(24));
515 TLorentzVector* jet2 = new TLorentzVector(fHijing->GetHINT1(31),
516 fHijing->GetHINT1(32),
517 fHijing->GetHINT1(33),
518 fHijing->GetHINT1(34));
519 // After final state gluon radiation.
520 TLorentzVector* jet3 = new TLorentzVector(fHijing->GetHINT1(26),
521 fHijing->GetHINT1(27),
522 fHijing->GetHINT1(28),
523 fHijing->GetHINT1(29));
525 TLorentzVector* jet4 = new TLorentzVector(fHijing->GetHINT1(36),
526 fHijing->GetHINT1(37),
527 fHijing->GetHINT1(38),
528 fHijing->GetHINT1(39));
529 ((AliGenHijingEventHeader*) header)->SetJets(jet1, jet2, jet3, jet4);
530 // Bookkeeping for kinematic bias
531 ((AliGenHijingEventHeader*) header)->SetTrials(fTrials);
533 header->SetPrimaryVertex(fEventVertex);
534 gAlice->SetGenEventHeader(header);
535 fCollisionGeometry = (AliGenHijingEventHeader*) header;
538 Bool_t AliGenHijing::CheckTrigger()
540 // Check the kinematic trigger condition
542 Bool_t triggered = kFALSE;
548 TLorentzVector* jet1 = new TLorentzVector(fHijing->GetHINT1(26),
549 fHijing->GetHINT1(27),
550 fHijing->GetHINT1(28),
551 fHijing->GetHINT1(29));
553 TLorentzVector* jet2 = new TLorentzVector(fHijing->GetHINT1(36),
554 fHijing->GetHINT1(37),
555 fHijing->GetHINT1(38),
556 fHijing->GetHINT1(39));
557 Double_t eta1 = jet1->Eta();
558 Double_t eta2 = jet2->Eta();
559 Double_t phi1 = jet1->Phi();
560 Double_t phi2 = jet2->Phi();
561 // printf("\n Trigger: %f %f %f %f",
562 // fEtaMinJet, fEtaMaxJet, fPhiMinJet, fPhiMaxJet);
564 (eta1 < fEtaMaxJet && eta1 > fEtaMinJet &&
565 phi1 < fPhiMaxJet && phi1 > fPhiMinJet)
567 (eta2 < fEtaMaxJet && eta2 > fEtaMinJet &&
568 phi2 < fPhiMaxJet && phi2 > fPhiMinJet)
571 } else if (fTrigger == 2) {
574 Int_t np = fParticles->GetEntriesFast();
575 for (Int_t i = 0; i < np; i++) {
576 TParticle* part = (TParticle*) fParticles->At(i);
577 Int_t kf = part->GetPdgCode();
578 Int_t ks = part->GetStatusCode();
579 if (kf == 22 && ks == 40) {
580 Float_t phi = part->Phi();
581 Float_t eta = part->Eta();
582 if (eta < fEtaMaxJet &&
588 } // check phi,eta within limits
598 AliGenHijing& AliGenHijing::operator=(const AliGenHijing& rhs)
600 // Assignment operator