AliGenMC base class for AliGenParam and AliGenPythia commonalities.
[u/mrichter/AliRoot.git] / EVGEN / AliGenParam.cxx
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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$Log$
6ba00c52 18Revision 1.29 2001/03/27 10:58:41 morsch
19Initialize decayer before generation. Important if run inside cocktail.
20
771bbe45 21Revision 1.28 2001/03/09 13:01:41 morsch
22- enum constants for paramterisation type (particle family) moved to AliGen*lib.h
23- use AliGenGSIlib::kUpsilon, AliGenPHOSlib::kEtaPrime to access the constants
24
34f60c01 25Revision 1.27 2001/02/02 15:21:10 morsch
26Set high water mark after last particle.
27Use Vertex() method for Vertex.
28
d9ea0e3b 29Revision 1.26 2000/12/21 16:24:06 morsch
30Coding convention clean-up
31
675e9664 32Revision 1.25 2000/11/30 07:12:50 alibrary
33Introducing new Rndm and QA classes
34
65fb704d 35Revision 1.24 2000/10/18 19:11:27 hristov
36Division by zero fixed
37
919c2096 38Revision 1.23 2000/10/02 21:28:06 fca
39Removal of useless dependecies via forward declarations
40
94de3818 41Revision 1.22 2000/09/12 14:14:55 morsch
42Call fDecayer->ForceDecay() at the beginning of Generate().
43
00d6ce7d 44Revision 1.21 2000/09/08 15:39:01 morsch
45Handle the case fForceDecay=all during the generation, i.e. select all secondaries.
46
5ab0acc9 47Revision 1.20 2000/09/06 14:35:44 morsch
48Use AliDecayerPythia for particle decays.
49
fa480368 50Revision 1.19 2000/07/11 18:24:56 fca
51Coding convention corrections + few minor bug fixes
52
aee8290b 53Revision 1.18 2000/06/29 21:08:27 morsch
54All paramatrisation libraries derive from the pure virtual base class AliGenLib.
55This allows to pass a pointer to a library directly to AliGenParam and avoids the
56use of function pointers in Config.C.
57
b22ee262 58Revision 1.17 2000/06/09 20:33:30 morsch
59All coding rule violations except RS3 corrected
60
f87cfe57 61Revision 1.16 2000/05/02 07:51:31 morsch
62- Control precision of pT sampling TF1::SetNpx(..)
63- Correct initialisation of child-cuts in all constructors.
64- Most coding rule violations corrected.
65
749070b6 66Revision 1.15 2000/04/03 15:42:12 morsch
67Cuts on primary particles are separated from those on the decay products. Methods
68SetChildMomentumRange, SetChildPtRange, SetChildPhiRange, SetChildThetaRange added.
69
cc5d764c 70Revision 1.14 1999/11/09 07:38:48 fca
71Changes for compatibility with version 2.23 of ROOT
72
084c1b4a 73Revision 1.13 1999/11/04 11:30:31 fca
74Correct the logics for SetForceDecay
75
28337bc1 76Revision 1.12 1999/11/03 17:43:20 fca
77New version from G.Martinez & A.Morsch
78
886b6f73 79Revision 1.11 1999/09/29 09:24:14 fca
80Introduction of the Copyright and cvs Log
81
4c039060 82*/
83
fe4da5cc 84#include "AliGenParam.h"
fa480368 85#include "AliDecayerPythia.h"
fe4da5cc 86#include "AliGenMUONlib.h"
87#include "AliRun.h"
1578254f 88#include <TParticle.h>
fa480368 89#include <TParticlePDG.h>
90#include <TDatabasePDG.h>
91#include <TLorentzVector.h>
92
f87cfe57 93#include <TF1.h>
fe4da5cc 94
95ClassImp(AliGenParam)
96
97//------------------------------------------------------------
98
99 //Begin_Html
100 /*
1439f98e 101 <img src="picts/AliGenParam.gif">
fe4da5cc 102 */
103 //End_Html
104
105//____________________________________________________________
106//____________________________________________________________
107AliGenParam::AliGenParam()
fe4da5cc 108{
b22ee262 109// Deafault constructor
110 fPtPara = 0;
111 fYPara = 0;
34f60c01 112 fParam = 0;
113 fAnalog = kAnalog;
b22ee262 114 SetCutOnChild();
115 SetChildMomentumRange();
116 SetChildPtRange();
117 SetChildPhiRange();
118 SetChildThetaRange();
119 SetDeltaPt();
675e9664 120//
121// Set random number generator
122 sRandom = fRandom;
b22ee262 123}
124
34f60c01 125AliGenParam::AliGenParam(Int_t npart, AliGenLib * Library, Int_t param, char* tname):AliGenerator(npart)
b22ee262 126{
127// Constructor using number of particles parameterisation id and library
128
129 fPtParaFunc = Library->GetPt(param, tname);
130 fYParaFunc = Library->GetY (param, tname);
131 fIpParaFunc = Library->GetIp(param, tname);
132
133 fPtPara = 0;
134 fYPara = 0;
135 fParam = param;
34f60c01 136 fAnalog = kAnalog;
b22ee262 137 fChildSelect.Set(5);
138 for (Int_t i=0; i<5; i++) fChildSelect[i]=0;
139 SetForceDecay();
140 SetCutOnChild();
141 SetChildMomentumRange();
142 SetChildPtRange();
143 SetChildPhiRange();
144 SetChildThetaRange();
145 SetDeltaPt();
675e9664 146//
147// Set random number generator
148 sRandom = fRandom;
fe4da5cc 149}
150
151//____________________________________________________________
886b6f73 152
34f60c01 153AliGenParam::AliGenParam(Int_t npart, Int_t param, char* tname):AliGenerator(npart)
fe4da5cc 154{
b22ee262 155// Constructor using parameterisation id and number of particles
156//
675e9664 157 AliGenLib* pLibrary = new AliGenMUONlib();
b22ee262 158
675e9664 159 fPtParaFunc = pLibrary->GetPt(param, tname);
160 fYParaFunc = pLibrary->GetY (param, tname);
161 fIpParaFunc = pLibrary->GetIp(param, tname);
b22ee262 162
163 fPtPara = 0;
164 fYPara = 0;
165 fParam = param;
34f60c01 166 fAnalog = kAnalog;
b22ee262 167 fChildSelect.Set(5);
168 for (Int_t i=0; i<5; i++) fChildSelect[i]=0;
169 SetForceDecay();
170 SetCutOnChild();
171 SetChildMomentumRange();
172 SetChildPtRange();
173 SetChildPhiRange();
174 SetChildThetaRange();
175 SetDeltaPt();
fe4da5cc 176}
177
34f60c01 178AliGenParam::AliGenParam(Int_t npart, Int_t param,
886b6f73 179 Double_t (*PtPara) (Double_t*, Double_t*),
180 Double_t (*YPara ) (Double_t* ,Double_t*),
65fb704d 181 Int_t (*IpPara) (TRandom *))
886b6f73 182 :AliGenerator(npart)
183{
749070b6 184// Constructor
28337bc1 185// Gines Martinez 1/10/99
886b6f73 186 fPtParaFunc = PtPara;
187 fYParaFunc = YPara;
188 fIpParaFunc = IpPara;
28337bc1 189//
886b6f73 190 fPtPara = 0;
191 fYPara = 0;
192 fParam = param;
34f60c01 193 fAnalog = kAnalog;
886b6f73 194 fChildSelect.Set(5);
195 for (Int_t i=0; i<5; i++) fChildSelect[i]=0;
196 SetForceDecay();
197 SetCutOnChild();
749070b6 198 SetChildMomentumRange();
199 SetChildPtRange();
200 SetChildPhiRange();
201 SetChildThetaRange();
202 SetDeltaPt();
886b6f73 203}
204
f87cfe57 205
206AliGenParam::AliGenParam(const AliGenParam & Paramd)
207{
208// copy constructor
209}
210
fe4da5cc 211//____________________________________________________________
212AliGenParam::~AliGenParam()
213{
749070b6 214// Destructor
fe4da5cc 215 delete fPtPara;
216 delete fYPara;
217}
218
219//____________________________________________________________
220void AliGenParam::Init()
221{
749070b6 222// Initialisation
fa480368 223
224 fDecayer = new AliDecayerPythia();
fe4da5cc 225 //Begin_Html
226 /*
1439f98e 227 <img src="picts/AliGenParam.gif">
fe4da5cc 228 */
229 //End_Html
230
749070b6 231 fPtPara = new TF1("Pt-Parametrization",fPtParaFunc,fPtMin,fPtMax,0);
232// Set representation precision to 10 MeV
233 Int_t npx= Int_t((fPtMax-fPtMin)/fDeltaPt);
234
235 fPtPara->SetNpx(npx);
236
237 fYPara = new TF1("Y -Parametrization",fYParaFunc,fYMin,fYMax,0);
238 TF1* ptPara = new TF1("Pt-Parametrization",fPtParaFunc,0,15,0);
239 TF1* yPara = new TF1("Y -Parametrization",fYParaFunc,-6,6,0);
b7601ac4 240
fe4da5cc 241//
242// dN/dy| y=0
749070b6 243 Double_t y1=0;
244 Double_t y2=0;
245
246 fdNdy0=fYParaFunc(&y1,&y2);
fe4da5cc 247//
248// Integral over generation region
749070b6 249 Float_t intYS = yPara ->Integral(fYMin, fYMax);
250 Float_t intPt0 = ptPara->Integral(0,15);
251 Float_t intPtS = ptPara->Integral(fPtMin,fPtMax);
252 Float_t phiWgt=(fPhiMax-fPhiMin)/2./TMath::Pi();
34f60c01 253 if (fAnalog == kAnalog) {
749070b6 254 fYWgt = intYS/fdNdy0;
255 fPtWgt = intPtS/intPt0;
256 fParentWeight = fYWgt*fPtWgt*phiWgt/fNpart;
257 } else {
258 fYWgt = intYS/fdNdy0;
259 fPtWgt = (fPtMax-fPtMin)/intPt0;
260 fParentWeight = fYWgt*fPtWgt*phiWgt/fNpart;
261 }
fe4da5cc 262//
263// particle decay related initialization
00d6ce7d 264 fDecayer->SetForceDecay(fForceDecay);
fa480368 265 fDecayer->Init();
00d6ce7d 266
fe4da5cc 267//
268 switch (fForceDecay)
269 {
34f60c01 270 case kSemiElectronic:
271 case kDiElectron:
272 case kBJpsiDiElectron:
273 case kBPsiPrimeDiElectron:
fe4da5cc 274 fChildSelect[0]=11;
275 break;
34f60c01 276 case kSemiMuonic:
277 case kDiMuon:
278 case kBJpsiDiMuon:
279 case kBPsiPrimeDiMuon:
fe4da5cc 280 fChildSelect[0]=13;
281 break;
34f60c01 282 case kPiToMu:
b7601ac4 283 fChildSelect[0]=13;
284 break;
34f60c01 285 case kKaToMu:
b7601ac4 286 fChildSelect[0]=13;
287 break;
34f60c01 288 case kHadronicD:
675e9664 289// Implement me !!
290 break;
34f60c01 291 case kNoDecay:
886b6f73 292 break;
34f60c01 293 case kAll:
886b6f73 294 break;
fe4da5cc 295 }
fe4da5cc 296}
297
298//____________________________________________________________
299void AliGenParam::Generate()
300{
28337bc1 301//
302// Generate 'npart' of light and heavy mesons (J/Psi, upsilon or phi, Pion,
303// Kaons, Etas, Omegas) and Baryons (proton, antiprotons, neutrons and
304// antineutrons in the the desired theta, phi and momentum windows;
305// Gaussian smearing on the vertex is done if selected.
cc5d764c 306// The decay of heavy mesons is done using lujet,
307// and the childern particle are tracked by GEANT
308// However, light mesons are directly tracked by GEANT
309// setting fForceDecay = nodecay (SetForceDecay(nodecay))
28337bc1 310//
771bbe45 311//
312// Reinitialize decayer
313 fDecayer->Init();
314//
28337bc1 315 Float_t polar[3]= {0,0,0}; // Polarisation of the parent particle (for GEANT tracking)
316 Float_t origin0[3]; // Origin of the generated parent particle (for GEANT tracking)
317 Float_t pt, pl, ptot; // Transverse, logitudinal and total momenta of the parent particle
318 Float_t phi, theta; // Phi and theta spherical angles of the parent particle momentum
319 Float_t p[3], pc[3],
320 och[3], pch[10][3]; // Momentum, polarisation and origin of the children particles from lujet
fe4da5cc 321 Float_t ty, xmt;
21aaa175 322 Int_t nt, i, j, kfch[10];
fe4da5cc 323 Float_t wgtp, wgtch;
324 Double_t dummy;
09fd3ea2 325 static TClonesArray *particles;
fe4da5cc 326 //
09fd3ea2 327 if(!particles) particles=new TClonesArray("TParticle",1000);
fa480368 328
675e9664 329 static TDatabasePDG *pDataBase = new TDatabasePDG();
330 if(!pDataBase) pDataBase = new TDatabasePDG();
fe4da5cc 331 //
332 Float_t random[6];
28337bc1 333
334// Calculating vertex position per event
fe4da5cc 335 for (j=0;j<3;j++) origin0[j]=fOrigin[j];
aee8290b 336 if(fVertexSmear==kPerEvent) {
d9ea0e3b 337// Rndm(random,6);
338// for (j=0;j<3;j++) {
339// origin0[j]+=fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
340// TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
341// TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
342// }
343// }
344 Vertex();
345 for (j=0;j<3;j++) origin0[j]=fVertex[j];
fe4da5cc 346 }
d9ea0e3b 347
21aaa175 348 Int_t ipa=0;
28337bc1 349// Generating fNpart particles
21aaa175 350 while (ipa<fNpart) {
cc5d764c 351 while(1) {
fe4da5cc 352//
353// particle type
65fb704d 354 Int_t iPart = fIpParaFunc(fRandom);
fa480368 355 fChildWeight=(fDecayer->GetPartialBranchingRatio(iPart))*fParentWeight;
675e9664 356 TParticlePDG *particle = pDataBase->GetParticle(iPart);
fa480368 357 Float_t am = particle->Mass();
358
65fb704d 359 Rndm(random,2);
fe4da5cc 360//
361// phi
362 phi=fPhiMin+random[0]*(fPhiMax-fPhiMin);
363//
364// y
365 ty=Float_t(TMath::TanH(fYPara->GetRandom()));
366//
367// pT
34f60c01 368 if (fAnalog == kAnalog) {
fe4da5cc 369 pt=fPtPara->GetRandom();
370 wgtp=fParentWeight;
371 wgtch=fChildWeight;
372 } else {
373 pt=fPtMin+random[1]*(fPtMax-fPtMin);
374 Double_t ptd=pt;
375 wgtp=fParentWeight*fPtParaFunc(& ptd, &dummy);
376 wgtch=fChildWeight*fPtParaFunc(& ptd, &dummy);
377 }
378 xmt=sqrt(pt*pt+am*am);
919c2096 379 if (TMath::Abs(ty)==1) ty=0;
fe4da5cc 380 pl=xmt*ty/sqrt(1.-ty*ty);
381 theta=TMath::ATan2(pt,pl);
cc5d764c 382// Cut on theta
fe4da5cc 383 if(theta<fThetaMin || theta>fThetaMax) continue;
384 ptot=TMath::Sqrt(pt*pt+pl*pl);
cc5d764c 385// Cut on momentum
fe4da5cc 386 if(ptot<fPMin || ptot>fPMax) continue;
387 p[0]=pt*TMath::Cos(phi);
388 p[1]=pt*TMath::Sin(phi);
389 p[2]=pl;
aee8290b 390 if(fVertexSmear==kPerTrack) {
65fb704d 391 Rndm(random,6);
fe4da5cc 392 for (j=0;j<3;j++) {
393 origin0[j]=
394 fOrigin[j]+fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
395 TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
396 }
397 }
28337bc1 398
399// Looking at fForceDecay :
cc5d764c 400// if fForceDecay != none Primary particle decays using
401// AliPythia and children are tracked by GEANT
28337bc1 402//
cc5d764c 403// if fForceDecay == none Primary particle is tracked by GEANT
404// (In the latest, make sure that GEANT actually does all the decays you want)
fe4da5cc 405//
34f60c01 406 if (fForceDecay != kNoDecay) {
28337bc1 407// Using lujet to decay particle
886b6f73 408 Float_t energy=TMath::Sqrt(ptot*ptot+am*am);
fa480368 409 TLorentzVector pmom(p[0], p[1], p[2], energy);
410 fDecayer->Decay(iPart,&pmom);
fe4da5cc 411//
cc5d764c 412// select decay particles
fa480368 413 Int_t np=fDecayer->ImportParticles(particles);
886b6f73 414 Int_t ncsel=0;
6ba00c52 415
416 if (np >1) {
417 TParticle* iparticle = (TParticle *) particles->At(0);
418 Int_t ipF = iparticle->GetFirstDaughter();
419 Int_t ipL = iparticle->GetLastDaughter();
420 for (i = ipF-1; i<ipL; i++) {
421 iparticle = (TParticle *) particles->At(i);
422 Int_t kf = iparticle->GetPdgCode();
fe4da5cc 423//
424// children
6ba00c52 425 if (ChildSelected(TMath::Abs(kf)) || fForceDecay == kAll)
426 {
427 pc[0]=iparticle->Px();
428 pc[1]=iparticle->Py();
429 pc[2]=iparticle->Pz();
430 och[0]=origin0[0]+iparticle->Vx()/10;
431 och[1]=origin0[1]+iparticle->Vy()/10;
432 och[2]=origin0[2]+iparticle->Vz()/10;
433 if (fCutOnChild) {
434 Float_t ptChild=TMath::Sqrt(pc[0]*pc[0]+pc[1]*pc[1]);
435 Float_t pChild=TMath::Sqrt(ptChild*ptChild+pc[2]*pc[2]);
436 Float_t thetaChild=TMath::ATan2(ptChild,pc[2]);
437 Float_t phiChild=TMath::ATan2(pc[1],pc[0]);
438 Bool_t childok =
439 ((ptChild > fChildPtMin && ptChild <fChildPtMax) &&
440 (pChild > fChildPMin && pChild <fChildPMax) &&
441 (thetaChild > fChildThetaMin && thetaChild <fChildThetaMax) &&
442 (phiChild > fChildPhiMin && phiChild <fChildPhiMax));
443 if(childok)
444 {
445 pch[ncsel][0]=pc[0];
446 pch[ncsel][1]=pc[1];
447 pch[ncsel][2]=pc[2];
448 kfch[ncsel]=kf;
449 ncsel++;
450 } else {
451 ncsel=-1;
452 break;
453 } // child kine cuts
454 } else {
886b6f73 455 pch[ncsel][0]=pc[0];
456 pch[ncsel][1]=pc[1];
457 pch[ncsel][2]=pc[2];
458 kfch[ncsel]=kf;
459 ncsel++;
6ba00c52 460 } // if child selection
461 } // select muon
462 } // decay particle loop
463 } // if decay products
464
886b6f73 465 Int_t iparent;
466 if ((fCutOnChild && ncsel >0) || !fCutOnChild){
467 ipa++;
21aaa175 468//
469// parent
886b6f73 470 gAlice->
65fb704d 471 SetTrack(0,-1,iPart,p,origin0,polar,0,kPPrimary,nt,wgtp);
886b6f73 472 iparent=nt;
f87cfe57 473 gAlice->KeepTrack(nt);
886b6f73 474 for (i=0; i< ncsel; i++) {
475 gAlice->SetTrack(fTrackIt,iparent,kfch[i],
476 &pch[i][0],och,polar,
65fb704d 477 0,kPDecay,nt,wgtch);
886b6f73 478 gAlice->KeepTrack(nt);
479 }
28337bc1 480 } // Decays by Lujet
21aaa175 481 } // kinematic selection
28337bc1 482 else // nodecay option, so parent will be tracked by GEANT (pions, kaons, eta, omegas, baryons)
483 {
484 gAlice->
65fb704d 485 SetTrack(fTrackIt,-1,iPart,p,origin0,polar,0,kPPrimary,nt,wgtp);
28337bc1 486 ipa++;
487 }
fe4da5cc 488 break;
21aaa175 489 } // while
fe4da5cc 490 } // event loop
d9ea0e3b 491 gAlice->SetHighWaterMark(nt);
492
fe4da5cc 493}
494
495Bool_t AliGenParam::ChildSelected(Int_t ip)
496{
749070b6 497// True if particle is in list of selected children
fe4da5cc 498 for (Int_t i=0; i<5; i++)
499 {
500 if (fChildSelect[i]==ip) return kTRUE;
501 }
502 return kFALSE;
503}
504
1578254f 505Bool_t AliGenParam::KinematicSelection(TParticle *particle)
fe4da5cc 506{
749070b6 507// Perform kinematic cuts
1578254f 508 Float_t px=particle->Px();
509 Float_t py=particle->Py();
510 Float_t pz=particle->Pz();
fe4da5cc 511//
512// momentum cut
513 Float_t p=TMath::Sqrt(px*px+py*py+pz*pz);
514 if (p > fPMax || p < fPMin)
515 {
516// printf("\n failed p cut %f %f %f \n",p,fPMin,fPMax);
517 return kFALSE;
518 }
519 Float_t pt=TMath::Sqrt(px*px+py*py);
520
521//
522// theta cut
523 Float_t theta = Float_t(TMath::ATan2(Double_t(pt),Double_t(p)));
524 if (theta > fThetaMax || theta < fThetaMin)
525 {
526// printf("\n failed theta cut %f %f %f \n",theta,fThetaMin,fThetaMax);
527 return kFALSE;
528 }
529
530 return kTRUE;
531}
532
533
f87cfe57 534AliGenParam& AliGenParam::operator=(const AliGenParam& rhs)
535{
536// Assignment operator
537 return *this;
538}
539
fe4da5cc 540
541