Some new structure functions added.
[u/mrichter/AliRoot.git] / EVGEN / AliGenPythia.cxx
CommitLineData
4c039060 1/**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
3 * *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
6 * *
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 **************************************************************************/
15
16/*
17$Log$
c5d36e84 18Revision 1.39 2001/07/27 17:09:36 morsch
19Use local SetTrack, KeepTrack and SetHighWaterMark methods
20to delegate either to local stack or to stack owned by AliRun.
21(Piotr Skowronski, A.M.)
22
a99cf51f 23Revision 1.38 2001/07/13 10:58:54 morsch
24- Some coded moved to AliGenMC
25- Improved handling of secondary vertices.
26
fff02fee 27Revision 1.37 2001/06/28 11:17:28 morsch
28SetEventListRange setter added. Events in specified range are listed for
29debugging. (Yuri Kharlov)
30
11dfaf8d 31Revision 1.36 2001/03/30 07:05:49 morsch
32Final print-out in finish run.
33Write parton system for jet-production (preliminary solution).
34
9be6226f 35Revision 1.35 2001/03/09 13:03:40 morsch
36Process_t and Struc_Func_t moved to AliPythia.h
37
f1a48a38 38Revision 1.34 2001/02/14 15:50:40 hristov
39The last particle in event marked using SetHighWaterMark
40
28adac24 41Revision 1.33 2001/01/30 09:23:12 hristov
42Streamers removed (R.Brun)
43
a8a6107b 44Revision 1.32 2001/01/26 19:55:51 hristov
45Major upgrade of AliRoot code
46
2ab0c725 47Revision 1.31 2001/01/17 10:54:31 hristov
48Better protection against FPE
49
0f9e52a3 50Revision 1.30 2000/12/18 08:55:35 morsch
51Make AliPythia dependent generartors work with new scheme of random number generation
52
3356c022 53Revision 1.29 2000/12/04 11:22:03 morsch
54Init of sRandom as in 1.15
55
097ec7c1 56Revision 1.28 2000/12/02 11:41:39 morsch
57Use SetRandom() to initialize random number generator in constructor.
58
1ed25e11 59Revision 1.27 2000/11/30 20:29:02 morsch
60Initialise static variable sRandom in constructor: sRandom = fRandom;
61
ad1df918 62Revision 1.26 2000/11/30 07:12:50 alibrary
63Introducing new Rndm and QA classes
64
65fb704d 65Revision 1.25 2000/10/18 19:11:27 hristov
66Division by zero fixed
67
919c2096 68Revision 1.24 2000/09/18 10:41:35 morsch
69Add possibility to use nuclear structure functions from PDF library V8.
70
811826d8 71Revision 1.23 2000/09/14 14:05:40 morsch
72dito
73
819f84ad 74Revision 1.22 2000/09/14 14:02:22 morsch
75- Correct conversion from mm to cm when passing particle vertex to MC.
76- Correct handling of fForceDecay == all.
77
4451ef92 78Revision 1.21 2000/09/12 14:14:55 morsch
79Call fDecayer->ForceDecay() at the beginning of Generate().
80
00d6ce7d 81Revision 1.20 2000/09/06 14:29:33 morsch
82Use AliPythia for event generation an AliDecayPythia for decays.
83Correct handling of "nodecay" option
84
18edb254 85Revision 1.19 2000/07/11 18:24:56 fca
86Coding convention corrections + few minor bug fixes
87
aee8290b 88Revision 1.18 2000/06/30 12:40:34 morsch
89Pythia takes care of vertex smearing. Correct conversion from Pythia units (mm) to
90Geant units (cm).
91
1512e357 92Revision 1.17 2000/06/09 20:34:07 morsch
93All coding rule violations except RS3 corrected
94
f87cfe57 95Revision 1.16 2000/05/15 15:04:20 morsch
96The full event is written for fNtrack = -1
97Coding rule violations corrected.
98
5ddeb374 99Revision 1.15 2000/04/26 10:14:24 morsch
100Particles array has one entry more than pythia particle list. Upper bound of
101particle loop changed to np-1 (R. Guernane, AM)
102
2a0e6f5b 103Revision 1.14 2000/04/05 08:36:13 morsch
104Check status code of particles in Pythia event
105to avoid double counting as partonic state and final state particle.
106
23211d3e 107Revision 1.13 1999/11/09 07:38:48 fca
108Changes for compatibility with version 2.23 of ROOT
109
084c1b4a 110Revision 1.12 1999/11/03 17:43:20 fca
111New version from G.Martinez & A.Morsch
112
886b6f73 113Revision 1.11 1999/09/29 09:24:14 fca
114Introduction of the Copyright and cvs Log
4c039060 115*/
116
fe4da5cc 117#include "AliGenPythia.h"
fff02fee 118#include "AliGenPythiaEventHeader.h"
18edb254 119#include "AliDecayerPythia.h"
fe4da5cc 120#include "AliRun.h"
121#include "AliPythia.h"
18edb254 122#include "AliPDG.h"
1578254f 123#include <TParticle.h>
18edb254 124#include <TSystem.h>
f87cfe57 125
fe4da5cc 126 ClassImp(AliGenPythia)
127
128AliGenPythia::AliGenPythia()
fff02fee 129 :AliGenMC()
fe4da5cc 130{
18edb254 131// Default Constructor
132 fDecayer = new AliDecayerPythia();
11dfaf8d 133 SetEventListRange();
fe4da5cc 134}
135
136AliGenPythia::AliGenPythia(Int_t npart)
fff02fee 137 :AliGenMC(npart)
fe4da5cc 138{
139// default charm production at 5. 5 TeV
140// semimuonic decay
141// structure function GRVHO
142//
143 fXsection = 0.;
811826d8 144 fNucA1=0;
145 fNucA2=0;
fe4da5cc 146 SetProcess();
147 SetStrucFunc();
886b6f73 148 SetForceDecay();
fe4da5cc 149 SetPtHard();
150 SetEnergyCMS();
18edb254 151 fDecayer = new AliDecayerPythia();
1ed25e11 152 // Set random number generator
097ec7c1 153 sRandom=fRandom;
11dfaf8d 154 SetEventListRange();
fff02fee 155 fFlavorSelect = 0;
156 // Produced particles
157 fParticles = new TClonesArray("TParticle",1000);
c5d36e84 158 fEventVertex.Set(3);
fe4da5cc 159}
160
f87cfe57 161AliGenPythia::AliGenPythia(const AliGenPythia & Pythia)
162{
163// copy constructor
164}
165
fe4da5cc 166AliGenPythia::~AliGenPythia()
167{
5ddeb374 168// Destructor
fe4da5cc 169}
170
11dfaf8d 171void AliGenPythia::SetEventListRange(Int_t eventFirst, Int_t eventLast)
172{
173 // Set a range of event numbers, for which a table
174 // of generated particle will be printed
175 fDebugEventFirst = eventFirst;
176 fDebugEventLast = eventLast;
177 if (fDebugEventLast==-1) fDebugEventLast=fDebugEventFirst;
178}
179
fe4da5cc 180void AliGenPythia::Init()
181{
5ddeb374 182// Initialisation
18edb254 183 SetMC(AliPythia::Instance());
fe4da5cc 184 fPythia=(AliPythia*) fgMCEvGen;
185//
186 fParentWeight=1./Float_t(fNpart);
187//
188// Forward Paramters to the AliPythia object
00d6ce7d 189 fDecayer->SetForceDecay(fForceDecay);
18edb254 190 fDecayer->Init();
00d6ce7d 191
18edb254 192
fe4da5cc 193 fPythia->SetCKIN(3,fPtHardMin);
194 fPythia->SetCKIN(4,fPtHardMax);
811826d8 195 if (fNucA1 > 0 && fNucA2 > 0) fPythia->SetNuclei(fNucA1, fNucA2);
fe4da5cc 196 fPythia->ProcInit(fProcess,fEnergyCMS,fStrucFunc);
18edb254 197
198 // fPythia->Pylist(0);
199 // fPythia->Pystat(2);
fe4da5cc 200// Parent and Children Selection
201 switch (fProcess)
202 {
f1a48a38 203 case kPyCharm:
fff02fee 204 fParentSelect[0] = 411;
205 fParentSelect[1] = 421;
206 fParentSelect[2] = 431;
207 fParentSelect[3] = 4122;
208 fFlavorSelect = 4;
fe4da5cc 209 break;
f1a48a38 210 case kPyCharmUnforced:
fff02fee 211 fParentSelect[0] = 411;
212 fParentSelect[1] = 421;
213 fParentSelect[2] = 431;
214 fParentSelect[3]= 4122;
215 fFlavorSelect = 4;
fe4da5cc 216 break;
f1a48a38 217 case kPyBeauty:
fff02fee 218 fParentSelect[0]= 511;
219 fParentSelect[1]= 521;
220 fParentSelect[2]= 531;
221 fParentSelect[3]= 5122;
222 fParentSelect[4]= 5132;
223 fParentSelect[5]= 5232;
224 fParentSelect[6]= 5332;
225 fFlavorSelect = 5;
fe4da5cc 226 break;
f1a48a38 227 case kPyBeautyUnforced:
fff02fee 228 fParentSelect[0] = 511;
229 fParentSelect[1] = 521;
230 fParentSelect[2] = 531;
231 fParentSelect[3] = 5122;
232 fParentSelect[4] = 5132;
233 fParentSelect[5] = 5232;
234 fParentSelect[6] = 5332;
235 fFlavorSelect = 5;
fe4da5cc 236 break;
f1a48a38 237 case kPyJpsiChi:
238 case kPyJpsi:
fff02fee 239 fParentSelect[0] = 443;
fe4da5cc 240 break;
f1a48a38 241 case kPyMb:
242 case kPyJets:
243 case kPyDirectGamma:
5be1fe76 244 break;
fe4da5cc 245 }
fff02fee 246 AliGenMC::Init();
fe4da5cc 247}
248
249void AliGenPythia::Generate()
250{
5ddeb374 251// Generate one event
00d6ce7d 252 fDecayer->ForceDecay();
9be6226f 253 Float_t polar[3] = {0,0,0};
254 Float_t origin[3] = {0,0,0};
9be6226f 255 Float_t origin0[3] = {0,0,0};
fff02fee 256 Float_t p[3];
5be1fe76 257// converts from mm/c to s
258 const Float_t kconv=0.001/2.999792458e8;
fe4da5cc 259//
fe4da5cc 260 Int_t nt=0;
261 Int_t jev=0;
7921755b 262 Int_t j, kf;
fe4da5cc 263 fTrials=0;
fff02fee 264
265// Set collision vertex position
fe4da5cc 266 for (j=0;j<3;j++) origin0[j]=fOrigin[j];
aee8290b 267 if(fVertexSmear==kPerEvent) {
1512e357 268 fPythia->SetMSTP(151,1);
fe4da5cc 269 for (j=0;j<3;j++) {
fff02fee 270 fPythia->SetPARP(151+j, fOsigma[j]*10.);
fe4da5cc 271 }
aee8290b 272 } else if (fVertexSmear==kPerTrack) {
fe4da5cc 273 fPythia->SetMSTP(151,0);
fe4da5cc 274 }
fff02fee 275// event loop
fe4da5cc 276 while(1)
277 {
084c1b4a 278 fPythia->Pyevnt();
11dfaf8d 279 if (gAlice->GetEvNumber()>=fDebugEventFirst &&
280 gAlice->GetEvNumber()<=fDebugEventLast) fPythia->Pylist(1);
fe4da5cc 281 fTrials++;
fff02fee 282 fPythia->ImportParticles(fParticles,"All");
283
284//
285//
286//
287 Int_t i;
288
289 Int_t np = fParticles->GetEntriesFast();
290 Int_t* pParent = new Int_t[np];
291 Int_t* pSelected = new Int_t[np];
292 Int_t* trackIt = new Int_t[np];
293 for (i=0; i< np-1; i++) {
294 pParent[i] = -1;
295 pSelected[i] = 0;
296 }
fe4da5cc 297 printf("\n **************************************************%d\n",np);
fff02fee 298 Int_t nc = 0;
fe4da5cc 299 if (np == 0 ) continue;
c5d36e84 300// Get event vertex
301 TParticle* iparticle;
302 iparticle = (TParticle *) fParticles->At(0);
303 fEventVertex[0] = iparticle->Vx()/10.;
304 fEventVertex[1] = iparticle->Vy()/10.;
305 fEventVertex[2] = iparticle->Vz()/10.;
306//
f1a48a38 307 if (fProcess != kPyMb && fProcess != kPyJets && fProcess != kPyDirectGamma) {
fff02fee 308 for (i = 0; i<np-1; i++) {
c5d36e84 309 iparticle = (TParticle *) fParticles->At(i);
23211d3e 310 Int_t ks = iparticle->GetStatusCode();
a8228d85 311 kf = CheckPDGCode(iparticle->GetPdgCode());
fff02fee 312// No initial state partons
2a0e6f5b 313 if (ks==21) continue;
fe4da5cc 314//
fff02fee 315// Heavy Flavor Selection
5be1fe76 316//
fff02fee 317 // quark ?
318 kf = TMath::Abs(kf);
319 Int_t kfl = kf;
320 // meson ?
321 if (kfl > 10) kfl/=100;
322 // baryon
323 if (kfl > 10) kfl/=10;
324 if (kfl > 10) kfl/=10;
325
326 Int_t ipa = iparticle->GetFirstMother()-1;
327 Int_t kfMo = 0;
328
329 if (ipa > -1) {
330 TParticle * mother = (TParticle *) fParticles->At(ipa);
331 kfMo = TMath::Abs(mother->GetPdgCode());
332 }
333// printf("\n particle (all) %d %d %d", i, pSelected[i], kf);
334 if (kfl >= fFlavorSelect) {
5be1fe76 335//
fff02fee 336// Heavy flavor hadron or quark
fe4da5cc 337//
fff02fee 338// Kinematic seletion on final state heavy flavor mesons
339 if (ParentSelected(kf) && !KinematicSelection(iparticle, 0))
340 {
341 nc = -1;
342 break;
343 }
344 pSelected[i] = 1;
345// printf("\n particle (HF) %d %d %d", i, pSelected[i], kf);
346 } else {
347// Kinematic seletion on decay products
348 if (fCutOnChild && ParentSelected(kfMo) && ChildSelected(kf)
349 && !KinematicSelection(iparticle, 1))
350 {
351 nc = -1;
352 break;
353 }
fe4da5cc 354//
fff02fee 355// Decay products
356// Select if mother was selected and is not tracked
357
358 if (pSelected[ipa] &&
359 !trackIt[ipa] && // mother will be tracked ?
360 kfMo != 5 && // mother is b-quark, don't store fragments
361 kfMo != 4 && // mother is c-quark, don't store fragments
362 kf != 92) // don't store string
363 {
fe4da5cc 364//
fff02fee 365// Semi-stable or de-selected: diselect decay products:
fe4da5cc 366//
5be1fe76 367//
fff02fee 368 if (pSelected[i] == -1 || fDecayer->GetLifetime(kf) > 10e-15)
369 {
370 Int_t ipF = iparticle->GetFirstDaughter();
371 Int_t ipL = iparticle->GetLastDaughter();
372 if (ipF > 0) for (j = ipF-1; j < ipL; j++) pSelected[j] = -1;
373 }
374// printf("\n particle (decay) %d %d %d", i, pSelected[i], kf);
375 pSelected[i] = (pSelected[i] == -1) ? 0 : 1;
376 }
377 }
378 if (pSelected[i] == -1) pSelected[i] = 0;
379 if (!pSelected[i]) continue;
380 nc++;
381// Decision on tracking
382 trackIt[i] = 0;
383//
384// Track final state particle
385 if (ks == 1) trackIt[i] = 1;
386// Track semi-stable particles
387 if ((ks ==1) || (fDecayer->GetLifetime(kf)> 10e-15)) trackIt[i] = 1;
388// Track particles selected by process if undecayed.
389 if (fForceDecay == kNoDecay) {
390 if (ParentSelected(kf)) trackIt[i] = 1;
391 } else {
392 if (ParentSelected(kf)) trackIt[i] = 0;
393 }
394//
395//
396
397 } // particle selection loop
398 if (nc > -1) {
399 for (i = 0; i<np-1; i++) {
400 if (!pSelected[i]) continue;
401 TParticle * iparticle = (TParticle *) fParticles->At(i);
402 kf = CheckPDGCode(iparticle->GetPdgCode());
9be6226f 403 p[0]=iparticle->Px();
404 p[1]=iparticle->Py();
405 p[2]=iparticle->Pz();
406 origin[0]=origin0[0]+iparticle->Vx()/10.;
407 origin[1]=origin0[1]+iparticle->Vy()/10.;
408 origin[2]=origin0[2]+iparticle->Vz()/10.;
409 Float_t tof=kconv*iparticle->T();
fff02fee 410 Int_t ipa = iparticle->GetFirstMother()-1;
411 Int_t iparent = (ipa > -1) ? pParent[ipa] : -1;
412// printf("\n SetTrack %d %d %d %d", i, iparent, kf, trackIt[i]);
a99cf51f 413 SetTrack(fTrackIt*trackIt[i] ,
fff02fee 414 iparent, kf, p, origin, polar, tof, kPPrimary, nt, 1.);
415 pParent[i] = nt;
a99cf51f 416 KeepTrack(nt);
fff02fee 417 } // SetTrack loop
418 }
419 } else {
420 nc = GenerateMB();
5be1fe76 421 } // mb ?
fff02fee 422
fe4da5cc 423 if (nc > 0) {
5be1fe76 424 jev+=nc;
5ddeb374 425 if (jev >= fNpart || fNpart == -1) {
fe4da5cc 426 fKineBias=Float_t(fNpart)/Float_t(fTrials);
23211d3e 427 printf("\n Trials: %i %i %i\n",fTrials, fNpart, jev);
fe4da5cc 428 break;
429 }
430 }
431 } // event loop
a99cf51f 432 SetHighWaterMark(nt);
fe4da5cc 433// adjust weight due to kinematic selection
434 AdjustWeights();
435// get cross-section
436 fXsection=fPythia->GetPARI(1);
437}
438
fff02fee 439Int_t AliGenPythia::GenerateMB()
fe4da5cc 440{
fff02fee 441 Int_t i, kf, nt, iparent;
442 Int_t nc = 0;
443 Float_t p[3];
444 Float_t polar[3] = {0,0,0};
445 Float_t origin[3] = {0,0,0};
446 Float_t origin0[3] = {0,0,0};
447// converts from mm/c to s
448 const Float_t kconv=0.001/2.999792458e8;
4451ef92 449
fff02fee 450 Int_t np = fParticles->GetEntriesFast();
451 Int_t* pParent = new Int_t[np];
452 for (i=0; i< np-1; i++) pParent[i] = -1;
453
454 for (i = 0; i<np-1; i++) {
455 Int_t trackIt = 0;
456 TParticle * iparticle = (TParticle *) fParticles->At(i);
457 kf = CheckPDGCode(iparticle->GetPdgCode());
458 Int_t ks = iparticle->GetStatusCode();
459 Int_t km = iparticle->GetFirstMother();
460// printf("\n Particle: %d %d %d", i, kf, ks);
461
462 if ((ks == 1 && kf!=0 && KinematicSelection(iparticle, 0)) ||
463 (ks != 1) ||
464 (fProcess == kPyJets && ks == 21 && km == 0 && i>1)) {
465 nc++;
466 if (ks == 1) trackIt = 1;
467 Int_t ipa = iparticle->GetFirstMother()-1;
fe4da5cc 468
fff02fee 469 iparent = (ipa > -1) ? pParent[ipa] : -1;
fe4da5cc 470
471//
fff02fee 472// store track information
473 p[0]=iparticle->Px();
474 p[1]=iparticle->Py();
475 p[2]=iparticle->Pz();
476 origin[0]=origin0[0]+iparticle->Vx()/10.;
477 origin[1]=origin0[1]+iparticle->Vy()/10.;
478 origin[2]=origin0[2]+iparticle->Vz()/10.;
479 Float_t tof=kconv*iparticle->T();
a99cf51f 480 SetTrack(fTrackIt*trackIt, iparent, kf, p, origin, polar,
c5d36e84 481 tof, kPPrimary, nt);
a99cf51f 482 KeepTrack(nt);
fff02fee 483 pParent[i] = nt;
484 } // select particle
485 } // particle loop
486
487 if (pParent) delete[] pParent;
fe4da5cc 488
fff02fee 489 printf("\n I've put %i particles on the stack \n",nc);
490 MakeHeader();
491 return nc;
492}
fe4da5cc 493
fe4da5cc 494
fff02fee 495void AliGenPythia::FinishRun()
496{
497// Print x-section summary
498 fPythia->Pystat(1);
fe4da5cc 499}
fff02fee 500
fe4da5cc 501void AliGenPythia::AdjustWeights()
502{
5ddeb374 503// Adjust the weights after generation of all events
504//
5ddeb374 505 TParticle *part;
fe4da5cc 506 Int_t ntrack=gAlice->GetNtrack();
507 for (Int_t i=0; i<ntrack; i++) {
2ab0c725 508 part= gAlice->Particle(i);
5ddeb374 509 part->SetWeight(part->GetWeight()*fKineBias);
fe4da5cc 510 }
511}
811826d8 512
513void AliGenPythia::SetNuclei(Int_t a1, Int_t a2)
514{
515// Treat protons as inside nuclei with mass numbers a1 and a2
516 fNucA1 = a1;
517 fNucA2 = a2;
518}
fff02fee 519
520
521void AliGenPythia::MakeHeader()
522{
523// Builds the event header, to be called after each event
524 AliGenEventHeader* header = new AliGenPythiaEventHeader("Pythia");
c5d36e84 525 ((AliGenPythiaEventHeader*) header)->SetProcessType(fPythia->GetMSTI(1));
526 header->SetPrimaryVertex(fEventVertex);
527 gAlice->SetGenEventHeader(header);
fff02fee 528}
811826d8 529
530
f87cfe57 531AliGenPythia& AliGenPythia::operator=(const AliGenPythia& rhs)
532{
533// Assignment operator
534 return *this;
535}
fe4da5cc 536
537
811826d8 538
a8a6107b 539#ifdef never
18edb254 540void AliGenPythia::Streamer(TBuffer &R__b)
541{
542 // Stream an object of class AliGenPythia.
543
544 if (R__b.IsReading()) {
545 Version_t R__v = R__b.ReadVersion(); if (R__v) { }
546 AliGenerator::Streamer(R__b);
547 R__b >> (Int_t&)fProcess;
548 R__b >> (Int_t&)fStrucFunc;
549 R__b >> (Int_t&)fForceDecay;
550 R__b >> fEnergyCMS;
551 R__b >> fKineBias;
552 R__b >> fTrials;
553 fParentSelect.Streamer(R__b);
554 fChildSelect.Streamer(R__b);
555 R__b >> fXsection;
556// (AliPythia::Instance())->Streamer(R__b);
557 R__b >> fPtHardMin;
558 R__b >> fPtHardMax;
559// if (fDecayer) fDecayer->Streamer(R__b);
560 } else {
561 R__b.WriteVersion(AliGenPythia::IsA());
562 AliGenerator::Streamer(R__b);
563 R__b << (Int_t)fProcess;
564 R__b << (Int_t)fStrucFunc;
565 R__b << (Int_t)fForceDecay;
566 R__b << fEnergyCMS;
567 R__b << fKineBias;
568 R__b << fTrials;
569 fParentSelect.Streamer(R__b);
570 fChildSelect.Streamer(R__b);
571 R__b << fXsection;
572// R__b << fPythia;
573 R__b << fPtHardMin;
574 R__b << fPtHardMax;
575 // fDecayer->Streamer(R__b);
576 }
577}
a8a6107b 578#endif
18edb254 579