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 Revision 1.60 2002/07/19 14:49:03 morsch
21 Revision 1.59 2002/07/19 14:35:36 morsch
22 Count total number of trials. Print mean Q, x1, x2.
24 Revision 1.58 2002/07/17 10:04:09 morsch
25 SetYHard method added.
27 Revision 1.57 2002/05/22 13:22:53 morsch
28 Process kPyMbNonDiffr added.
30 Revision 1.56 2002/04/26 10:30:01 morsch
31 Option kPyBeautyPbMNR added. (N. Carrer).
33 Revision 1.55 2002/04/17 10:23:56 morsch
34 Coding Rule violations corrected.
36 Revision 1.54 2002/03/28 11:49:10 morsch
37 Pass status code in SetTrack.
39 Revision 1.53 2002/03/25 14:51:13 morsch
40 New stack-fill and count options introduced (N. Carrer).
42 Revision 1.51 2002/03/06 08:46:57 morsch
44 - delete dyn. alloc. arrays (N. Carrer)
46 Revision 1.50 2002/03/03 13:48:50 morsch
47 Option kPyCharmPbMNR added. Produce charm pairs in agreement with MNR
48 NLO calculations (Nicola Carrer).
50 Revision 1.49 2002/02/08 16:50:50 morsch
51 Add name and title in constructor.
53 Revision 1.48 2001/12/20 11:44:28 morsch
54 Add kinematic bias for direct gamma production.
56 Revision 1.47 2001/12/19 14:45:00 morsch
57 Store number of trials in header.
59 Revision 1.46 2001/12/19 10:36:19 morsch
60 Add possibility if jet kinematic biasing.
62 Revision 1.45 2001/11/28 08:06:52 morsch
63 Use fMaxLifeTime parameter.
65 Revision 1.44 2001/11/27 13:13:07 morsch
66 Maximum lifetime for long-lived particles to be put on the stack is parameter.
67 It can be set via SetMaximumLifetime(..).
69 Revision 1.43 2001/10/21 18:35:56 hristov
70 Several pointers were set to zero in the default constructors to avoid memory management problems
72 Revision 1.42 2001/10/15 08:21:55 morsch
73 Vertex truncation settings moved to AliGenMC.
75 Revision 1.41 2001/10/08 08:45:42 morsch
76 Possibility of vertex cut added.
78 Revision 1.40 2001/09/25 11:30:23 morsch
79 Pass event vertex to header.
81 Revision 1.39 2001/07/27 17:09:36 morsch
82 Use local SetTrack, KeepTrack and SetHighWaterMark methods
83 to delegate either to local stack or to stack owned by AliRun.
84 (Piotr Skowronski, A.M.)
86 Revision 1.38 2001/07/13 10:58:54 morsch
87 - Some coded moved to AliGenMC
88 - Improved handling of secondary vertices.
90 Revision 1.37 2001/06/28 11:17:28 morsch
91 SetEventListRange setter added. Events in specified range are listed for
92 debugging. (Yuri Kharlov)
94 Revision 1.36 2001/03/30 07:05:49 morsch
95 Final print-out in finish run.
96 Write parton system for jet-production (preliminary solution).
98 Revision 1.35 2001/03/09 13:03:40 morsch
99 Process_t and Struc_Func_t moved to AliPythia.h
101 Revision 1.34 2001/02/14 15:50:40 hristov
102 The last particle in event marked using SetHighWaterMark
104 Revision 1.33 2001/01/30 09:23:12 hristov
105 Streamers removed (R.Brun)
107 Revision 1.32 2001/01/26 19:55:51 hristov
108 Major upgrade of AliRoot code
110 Revision 1.31 2001/01/17 10:54:31 hristov
111 Better protection against FPE
113 Revision 1.30 2000/12/18 08:55:35 morsch
114 Make AliPythia dependent generartors work with new scheme of random number generation
116 Revision 1.29 2000/12/04 11:22:03 morsch
117 Init of sRandom as in 1.15
119 Revision 1.28 2000/12/02 11:41:39 morsch
120 Use SetRandom() to initialize random number generator in constructor.
122 Revision 1.27 2000/11/30 20:29:02 morsch
123 Initialise static variable sRandom in constructor: sRandom = fRandom;
125 Revision 1.26 2000/11/30 07:12:50 alibrary
126 Introducing new Rndm and QA classes
128 Revision 1.25 2000/10/18 19:11:27 hristov
129 Division by zero fixed
131 Revision 1.24 2000/09/18 10:41:35 morsch
132 Add possibility to use nuclear structure functions from PDF library V8.
134 Revision 1.23 2000/09/14 14:05:40 morsch
137 Revision 1.22 2000/09/14 14:02:22 morsch
138 - Correct conversion from mm to cm when passing particle vertex to MC.
139 - Correct handling of fForceDecay == all.
141 Revision 1.21 2000/09/12 14:14:55 morsch
142 Call fDecayer->ForceDecay() at the beginning of Generate().
144 Revision 1.20 2000/09/06 14:29:33 morsch
145 Use AliPythia for event generation an AliDecayPythia for decays.
146 Correct handling of "nodecay" option
148 Revision 1.19 2000/07/11 18:24:56 fca
149 Coding convention corrections + few minor bug fixes
151 Revision 1.18 2000/06/30 12:40:34 morsch
152 Pythia takes care of vertex smearing. Correct conversion from Pythia units (mm) to
155 Revision 1.17 2000/06/09 20:34:07 morsch
156 All coding rule violations except RS3 corrected
158 Revision 1.16 2000/05/15 15:04:20 morsch
159 The full event is written for fNtrack = -1
160 Coding rule violations corrected.
162 Revision 1.15 2000/04/26 10:14:24 morsch
163 Particles array has one entry more than pythia particle list. Upper bound of
164 particle loop changed to np-1 (R. Guernane, AM)
166 Revision 1.14 2000/04/05 08:36:13 morsch
167 Check status code of particles in Pythia event
168 to avoid double counting as partonic state and final state particle.
170 Revision 1.13 1999/11/09 07:38:48 fca
171 Changes for compatibility with version 2.23 of ROOT
173 Revision 1.12 1999/11/03 17:43:20 fca
174 New version from G.Martinez & A.Morsch
176 Revision 1.11 1999/09/29 09:24:14 fca
177 Introduction of the Copyright and cvs Log
181 // Generator using the TPythia interface (via AliPythia)
182 // to generate pp collisions.
183 // Using SetNuclei() also nuclear modifications to the structure functions
184 // can be taken into account. This makes, of course, only sense for the
185 // generation of the products of hard processes (heavy flavor, jets ...)
187 // andreas.morsch@cern.ch
191 #include "AliGenPythia.h"
192 #include "AliGenPythiaEventHeader.h"
193 #include "AliDecayerPythia.h"
195 #include "AliPythia.h"
197 #include <TParticle.h>
200 ClassImp(AliGenPythia)
202 AliGenPythia::AliGenPythia()
205 // Default Constructor
208 fDecayer = new AliDecayerPythia();
216 AliGenPythia::AliGenPythia(Int_t npart)
219 // default charm production at 5. 5 TeV
221 // structure function GRVHO
224 fTitle= "Particle Generator using PYTHIA";
234 fDecayer = new AliDecayerPythia();
235 // Set random number generator
238 // Produced particles
239 fParticles = new TClonesArray("TParticle",1000);
246 // Options determining what to keep in the stack (Heavy flavour generation)
247 fStackFillOpt = kFlavorSelection; // Keep particle with selected flavor
248 fFeedDownOpt = kTRUE; // allow feed down from higher family
249 // Fragmentation on/off
250 fFragmentation = kTRUE;
251 // Default counting mode
252 fCountMode = kCountAll;
255 AliGenPythia::AliGenPythia(const AliGenPythia & Pythia)
261 AliGenPythia::~AliGenPythia()
266 void AliGenPythia::SetEventListRange(Int_t eventFirst, Int_t eventLast)
268 // Set a range of event numbers, for which a table
269 // of generated particle will be printed
270 fDebugEventFirst = eventFirst;
271 fDebugEventLast = eventLast;
272 if (fDebugEventLast==-1) fDebugEventLast=fDebugEventFirst;
275 void AliGenPythia::Init()
278 SetMC(AliPythia::Instance());
279 fPythia=(AliPythia*) fgMCEvGen;
281 fParentWeight=1./Float_t(fNpart);
283 // Forward Paramters to the AliPythia object
284 fDecayer->SetForceDecay(fForceDecay);
288 fPythia->SetCKIN(3,fPtHardMin);
289 fPythia->SetCKIN(4,fPtHardMax);
290 fPythia->SetCKIN(7,fYHardMin);
291 fPythia->SetCKIN(8,fYHardMax);
293 if (fNucA1 > 0 && fNucA2 > 0) fPythia->SetNuclei(fNucA1, fNucA2);
295 if (fFragmentation) {
296 fPythia->SetMSTP(111,1);
298 fPythia->SetMSTP(111,0);
301 fPythia->ProcInit(fProcess,fEnergyCMS,fStrucFunc);
303 // fPythia->Pylist(0);
304 // fPythia->Pystat(2);
305 // Parent and Children Selection
309 case kPyCharmUnforced:
311 fParentSelect[0] = 411;
312 fParentSelect[1] = 421;
313 fParentSelect[2] = 431;
314 fParentSelect[3] = 4122;
318 fParentSelect[0] = 421;
323 fParentSelect[0]= 511;
324 fParentSelect[1]= 521;
325 fParentSelect[2]= 531;
326 fParentSelect[3]= 5122;
327 fParentSelect[4]= 5132;
328 fParentSelect[5]= 5232;
329 fParentSelect[6]= 5332;
332 case kPyBeautyUnforced:
333 fParentSelect[0] = 511;
334 fParentSelect[1] = 521;
335 fParentSelect[2] = 531;
336 fParentSelect[3] = 5122;
337 fParentSelect[4] = 5132;
338 fParentSelect[5] = 5232;
339 fParentSelect[6] = 5332;
344 fParentSelect[0] = 443;
353 // This counts the total number of calls to Pyevnt() per run.
363 void AliGenPythia::Generate()
365 // Generate one event
366 fDecayer->ForceDecay();
368 Float_t polar[3] = {0,0,0};
369 Float_t origin[3] = {0,0,0};
371 // converts from mm/c to s
372 const Float_t kconv=0.001/2.999792458e8;
379 // Set collision vertex position
380 if(fVertexSmear==kPerEvent) {
381 fPythia->SetMSTP(151,1);
383 fPythia->SetPARP(151+j, fOsigma[j]*10.);
385 } else if (fVertexSmear==kPerTrack) {
386 fPythia->SetMSTP(151,0);
392 if (gAlice->GetEvNumber()>=fDebugEventFirst &&
393 gAlice->GetEvNumber()<=fDebugEventLast) fPythia->Pylist(1);
396 fPythia->ImportParticles(fParticles,"All");
403 Int_t np = fParticles->GetEntriesFast();
404 if (np == 0 ) continue;
405 // Get event vertex and discard the event if the Z coord. is too big
406 TParticle *iparticle = (TParticle *) fParticles->At(0);
407 Float_t distz = iparticle->Vz()/10.;
408 if(TMath::Abs(distz)>fCutVertexZ*fOsigma[2]) continue;
410 fEventVertex[0] = iparticle->Vx()/10.+fOrigin.At(0);
411 fEventVertex[1] = iparticle->Vy()/10.+fOrigin.At(1);
412 fEventVertex[2] = iparticle->Vz()/10.+fOrigin.At(2);
414 Int_t* pParent = new Int_t[np];
415 Int_t* pSelected = new Int_t[np];
416 Int_t* trackIt = new Int_t[np];
417 for (i=0; i< np; i++) {
423 Int_t nc = 0; // Total n. of selected particles
424 Int_t nParents = 0; // Selected parents
425 Int_t nTkbles = 0; // Trackable particles
426 if (fProcess != kPyMb && fProcess != kPyJets &&
427 fProcess != kPyDirectGamma &&
428 fProcess != kPyMbNonDiffr) {
430 for (i = 0; i<np; i++) {
431 iparticle = (TParticle *) fParticles->At(i);
432 Int_t ks = iparticle->GetStatusCode();
433 kf = CheckPDGCode(iparticle->GetPdgCode());
434 // No initial state partons
435 if (ks==21) continue;
437 // Heavy Flavor Selection
443 if (kfl > 10) kfl/=100;
445 if (kfl > 10) kfl/=10;
446 if (kfl > 10) kfl/=10;
448 Int_t ipa = iparticle->GetFirstMother()-1;
452 TParticle * mother = (TParticle *) fParticles->At(ipa);
453 kfMo = TMath::Abs(mother->GetPdgCode());
455 // What to keep in Stack?
456 Bool_t flavorOK = kFALSE;
457 Bool_t selectOK = kFALSE;
459 if (kfl >= fFlavorSelect) flavorOK = kTRUE;
461 if (kfl > fFlavorSelect) {
465 if (kfl == fFlavorSelect) flavorOK = kTRUE;
467 switch (fStackFillOpt) {
468 case kFlavorSelection:
471 case kParentSelection:
472 if (ParentSelected(kf) || kf <= 10) selectOK = kTRUE;
475 if (flavorOK && selectOK) {
477 // Heavy flavor hadron or quark
479 // Kinematic seletion on final state heavy flavor mesons
480 if (ParentSelected(kf) && !KinematicSelection(iparticle, 0))
485 if (ParentSelected(kf)) ++nParents; // Update parent count
486 // printf("\n particle (HF) %d %d %d", i, pSelected[i], kf);
488 // Kinematic seletion on decay products
489 if (fCutOnChild && ParentSelected(kfMo) && ChildSelected(kf)
490 && !KinematicSelection(iparticle, 1))
496 // Select if mother was selected and is not tracked
498 if (pSelected[ipa] &&
499 !trackIt[ipa] && // mother will be tracked ?
500 kfMo != 5 && // mother is b-quark, don't store fragments
501 kfMo != 4 && // mother is c-quark, don't store fragments
502 kf != 92) // don't store string
505 // Semi-stable or de-selected: diselect decay products:
508 if (pSelected[i] == -1 || fDecayer->GetLifetime(kf) > fMaxLifeTime)
510 Int_t ipF = iparticle->GetFirstDaughter();
511 Int_t ipL = iparticle->GetLastDaughter();
512 if (ipF > 0) for (j = ipF-1; j < ipL; j++) pSelected[j] = -1;
514 // printf("\n particle (decay) %d %d %d", i, pSelected[i], kf);
515 pSelected[i] = (pSelected[i] == -1) ? 0 : 1;
518 if (pSelected[i] == -1) pSelected[i] = 0;
519 if (!pSelected[i]) continue;
520 // Count quarks only if you did not include fragmentation
521 if (fFragmentation && kf <= 10) continue;
523 // Decision on tracking
526 // Track final state particle
527 if (ks == 1) trackIt[i] = 1;
528 // Track semi-stable particles
529 if ((ks ==1) || (fDecayer->GetLifetime(kf) > fMaxLifeTime)) trackIt[i] = 1;
530 // Track particles selected by process if undecayed.
531 if (fForceDecay == kNoDecay) {
532 if (ParentSelected(kf)) trackIt[i] = 1;
534 if (ParentSelected(kf)) trackIt[i] = 0;
536 if (trackIt[i] == 1) ++nTkbles; // Update trackable counter
540 } // particle selection loop
542 for (i = 0; i<np; i++) {
543 if (!pSelected[i]) continue;
544 TParticle * iparticle = (TParticle *) fParticles->At(i);
545 kf = CheckPDGCode(iparticle->GetPdgCode());
546 Int_t ks = iparticle->GetStatusCode();
547 p[0] = iparticle->Px();
548 p[1] = iparticle->Py();
549 p[2] = iparticle->Pz();
550 origin[0] = fOrigin[0]+iparticle->Vx()/10.;
551 origin[1] = fOrigin[1]+iparticle->Vy()/10.;
552 origin[2] = fOrigin[2]+iparticle->Vz()/10.;
553 Float_t tof = kconv*iparticle->T();
554 Int_t ipa = iparticle->GetFirstMother()-1;
555 Int_t iparent = (ipa > -1) ? pParent[ipa] : -1;
556 SetTrack(fTrackIt*trackIt[i] ,
557 iparent, kf, p, origin, polar, tof, kPPrimary, nt, 1., ks);
566 if (pParent) delete[] pParent;
567 if (pSelected) delete[] pSelected;
568 if (trackIt) delete[] trackIt;
571 switch (fCountMode) {
573 // printf(" Count all \n");
577 // printf(" Count parents \n");
580 case kCountTrackables:
581 // printf(" Count trackable \n");
585 if (jev >= fNpart || fNpart == -1) {
586 fKineBias=Float_t(fNpart)/Float_t(fTrials);
587 printf("\n Trials: %i %i %i\n",fTrials, fNpart, jev);
589 fQ += fPythia->GetVINT(51);
590 fX1 += fPythia->GetVINT(41);
591 fX2 += fPythia->GetVINT(42);
592 fTrialsRun += fTrials;
599 SetHighWaterMark(nt);
600 // adjust weight due to kinematic selection
603 fXsection=fPythia->GetPARI(1);
606 Int_t AliGenPythia::GenerateMB()
609 // Min Bias selection and other global selections
611 Int_t i, kf, nt, iparent;
614 Float_t polar[3] = {0,0,0};
615 Float_t origin[3] = {0,0,0};
616 // converts from mm/c to s
617 const Float_t kconv=0.001/2.999792458e8;
619 Int_t np = fParticles->GetEntriesFast();
620 Int_t* pParent = new Int_t[np];
621 for (i=0; i< np; i++) pParent[i] = -1;
622 if (fProcess == kPyJets || fProcess == kPyDirectGamma) {
623 TParticle* jet1 = (TParticle *) fParticles->At(6);
624 TParticle* jet2 = (TParticle *) fParticles->At(7);
625 if (!CheckTrigger(jet1, jet2)) return 0;
628 for (i = 0; i<np; i++) {
630 TParticle * iparticle = (TParticle *) fParticles->At(i);
631 kf = CheckPDGCode(iparticle->GetPdgCode());
632 Int_t ks = iparticle->GetStatusCode();
633 Int_t km = iparticle->GetFirstMother();
634 if ((ks == 1 && kf!=0 && KinematicSelection(iparticle, 0)) ||
636 (fProcess == kPyJets && ks == 21 && km == 0 && i>1)) {
638 if (ks == 1) trackIt = 1;
639 Int_t ipa = iparticle->GetFirstMother()-1;
641 iparent = (ipa > -1) ? pParent[ipa] : -1;
644 // store track information
645 p[0] = iparticle->Px();
646 p[1] = iparticle->Py();
647 p[2] = iparticle->Pz();
648 origin[0] = fOrigin[0]+iparticle->Vx()/10.;
649 origin[1] = fOrigin[1]+iparticle->Vy()/10.;
650 origin[2] = fOrigin[2]+iparticle->Vz()/10.;
651 Float_t tof=kconv*iparticle->T();
652 SetTrack(fTrackIt*trackIt, iparent, kf, p, origin, polar,
653 tof, kPPrimary, nt, 1., ks);
659 if (pParent) delete[] pParent;
661 printf("\n I've put %i particles on the stack \n",nc);
666 void AliGenPythia::FinishRun()
668 // Print x-section summary
673 printf("\nTotal number of Pyevnt() calls %d\n", fTrialsRun);
674 printf("\nMean Q, x1, x2: %f %f %f\n", fQ, fX1, fX2);
679 void AliGenPythia::AdjustWeights()
681 // Adjust the weights after generation of all events
684 Int_t ntrack=gAlice->GetNtrack();
685 for (Int_t i=0; i<ntrack; i++) {
686 part= gAlice->Particle(i);
687 part->SetWeight(part->GetWeight()*fKineBias);
691 void AliGenPythia::SetNuclei(Int_t a1, Int_t a2)
693 // Treat protons as inside nuclei with mass numbers a1 and a2
699 void AliGenPythia::MakeHeader() const
701 // Builds the event header, to be called after each event
702 AliGenEventHeader* header = new AliGenPythiaEventHeader("Pythia");
703 ((AliGenPythiaEventHeader*) header)->SetProcessType(fPythia->GetMSTI(1));
704 ((AliGenPythiaEventHeader*) header)->SetTrials(fTrials);
705 header->SetPrimaryVertex(fEventVertex);
706 gAlice->SetGenEventHeader(header);
710 Bool_t AliGenPythia::CheckTrigger(TParticle* jet1, TParticle* jet2) const
712 // Check the kinematic trigger condition
715 eta[0] = jet1->Eta();
716 eta[1] = jet2->Eta();
718 phi[0] = jet1->Phi();
719 phi[1] = jet2->Phi();
721 pdg[0] = jet1->GetPdgCode();
722 pdg[1] = jet2->GetPdgCode();
723 Bool_t triggered = kFALSE;
725 if (fProcess == kPyJets) {
726 //Check eta range first...
727 if ((eta[0] < fEtaMaxJet && eta[0] > fEtaMinJet) ||
728 (eta[1] < fEtaMaxJet && eta[1] > fEtaMinJet))
730 //Eta is okay, now check phi range
731 if ((phi[0] < fPhiMaxJet && phi[0] > fPhiMinJet) ||
732 (phi[1] < fPhiMaxJet && phi[1] > fPhiMinJet))
740 if (pdg[0] == kGamma) {
744 //Check eta range first...
745 if ((eta[ij] < fEtaMaxJet && eta[ij] > fEtaMinJet) &&
746 (eta[ig] < fEtaMaxGamma && eta[ig] > fEtaMinGamma))
748 //Eta is okay, now check phi range
749 if ((phi[ij] < fPhiMaxJet && phi[ij] > fPhiMinJet) &&
750 (phi[ig] < fPhiMaxGamma && phi[ig] > fPhiMinGamma))
759 AliGenPythia& AliGenPythia::operator=(const AliGenPythia& rhs)
761 // Assignment operator
768 void AliGenPythia::Streamer(TBuffer &R__b)
770 // Stream an object of class AliGenPythia.
772 if (R__b.IsReading()) {
773 Version_t R__v = R__b.ReadVersion(); if (R__v) { }
774 AliGenerator::Streamer(R__b);
775 R__b >> (Int_t&)fProcess;
776 R__b >> (Int_t&)fStrucFunc;
777 R__b >> (Int_t&)fForceDecay;
781 fParentSelect.Streamer(R__b);
782 fChildSelect.Streamer(R__b);
784 // (AliPythia::Instance())->Streamer(R__b);
787 // if (fDecayer) fDecayer->Streamer(R__b);
789 R__b.WriteVersion(AliGenPythia::IsA());
790 AliGenerator::Streamer(R__b);
791 R__b << (Int_t)fProcess;
792 R__b << (Int_t)fStrucFunc;
793 R__b << (Int_t)fForceDecay;
797 fParentSelect.Streamer(R__b);
798 fChildSelect.Streamer(R__b);
803 // fDecayer->Streamer(R__b);