fFilename !-ed
[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$Log$
f87cfe57 18Revision 1.16 2000/05/02 07:51:31 morsch
19- Control precision of pT sampling TF1::SetNpx(..)
20- Correct initialisation of child-cuts in all constructors.
21- Most coding rule violations corrected.
22
749070b6 23Revision 1.15 2000/04/03 15:42:12 morsch
24Cuts on primary particles are separated from those on the decay products. Methods
25SetChildMomentumRange, SetChildPtRange, SetChildPhiRange, SetChildThetaRange added.
26
cc5d764c 27Revision 1.14 1999/11/09 07:38:48 fca
28Changes for compatibility with version 2.23 of ROOT
29
084c1b4a 30Revision 1.13 1999/11/04 11:30:31 fca
31Correct the logics for SetForceDecay
32
28337bc1 33Revision 1.12 1999/11/03 17:43:20 fca
34New version from G.Martinez & A.Morsch
35
886b6f73 36Revision 1.11 1999/09/29 09:24:14 fca
37Introduction of the Copyright and cvs Log
38
4c039060 39*/
40
fe4da5cc 41#include "AliGenParam.h"
42#include "AliGenMUONlib.h"
43#include "AliRun.h"
fe4da5cc 44#include "AliPythia.h"
1578254f 45#include <TParticle.h>
f87cfe57 46#include <TF1.h>
fe4da5cc 47
48ClassImp(AliGenParam)
49
50//------------------------------------------------------------
51
52 //Begin_Html
53 /*
1439f98e 54 <img src="picts/AliGenParam.gif">
fe4da5cc 55 */
56 //End_Html
57
58//____________________________________________________________
59//____________________________________________________________
60AliGenParam::AliGenParam()
61 :AliGenerator()
62{
749070b6 63// Constructor
fe4da5cc 64 fPtPara = 0;
65 fYPara = 0;
b7601ac4 66 fParam = jpsi_p;
67 fAnalog = analog;
21aaa175 68 SetCutOnChild();
cc5d764c 69 SetChildMomentumRange();
70 SetChildPtRange();
71 SetChildPhiRange();
72 SetChildThetaRange();
749070b6 73 SetDeltaPt();
fe4da5cc 74}
75
76//____________________________________________________________
886b6f73 77
78AliGenParam::AliGenParam(Int_t npart, Param_t param) :AliGenerator(npart)
fe4da5cc 79{
749070b6 80// Constructor
fe4da5cc 81 //
82 // fName="HMESONpara";
83 // fTitle="Heavy Mesons Parametrisation";
b7601ac4 84 fPtParaFunc = AliGenMUONlib::GetPt(param);
85 fYParaFunc = AliGenMUONlib::GetY(param);
86 fIpParaFunc = AliGenMUONlib::GetIp(param);
fe4da5cc 87
88 fPtPara = 0;
89 fYPara = 0;
b7601ac4 90 fParam = param;
91 fAnalog = analog;
fe4da5cc 92 fChildSelect.Set(5);
93 for (Int_t i=0; i<5; i++) fChildSelect[i]=0;
886b6f73 94 SetForceDecay();
21aaa175 95 SetCutOnChild();
cc5d764c 96 SetChildMomentumRange();
97 SetChildPtRange();
98 SetChildPhiRange();
749070b6 99 SetChildThetaRange();
100 SetDeltaPt();
fe4da5cc 101}
102
886b6f73 103AliGenParam::AliGenParam(Int_t npart, Param_t param,
104 Double_t (*PtPara) (Double_t*, Double_t*),
105 Double_t (*YPara ) (Double_t* ,Double_t*),
106 Int_t (*IpPara) ())
107 :AliGenerator(npart)
108{
749070b6 109// Constructor
28337bc1 110// Gines Martinez 1/10/99
886b6f73 111 fPtParaFunc = PtPara;
112 fYParaFunc = YPara;
113 fIpParaFunc = IpPara;
28337bc1 114//
886b6f73 115 fPtPara = 0;
116 fYPara = 0;
117 fParam = param;
118 fAnalog = analog;
119 fChildSelect.Set(5);
120 for (Int_t i=0; i<5; i++) fChildSelect[i]=0;
121 SetForceDecay();
122 SetCutOnChild();
749070b6 123 SetChildMomentumRange();
124 SetChildPtRange();
125 SetChildPhiRange();
126 SetChildThetaRange();
127 SetDeltaPt();
886b6f73 128}
129
f87cfe57 130
131AliGenParam::AliGenParam(const AliGenParam & Paramd)
132{
133// copy constructor
134}
135
fe4da5cc 136//____________________________________________________________
137AliGenParam::~AliGenParam()
138{
749070b6 139// Destructor
fe4da5cc 140 delete fPtPara;
141 delete fYPara;
142}
143
144//____________________________________________________________
145void AliGenParam::Init()
146{
749070b6 147// Initialisation
fe4da5cc 148 SetMC(new AliPythia());
149 fPythia= (AliPythia*) fgMCEvGen;
749070b6 150
fe4da5cc 151 //Begin_Html
152 /*
1439f98e 153 <img src="picts/AliGenParam.gif">
fe4da5cc 154 */
155 //End_Html
156
749070b6 157 fPtPara = new TF1("Pt-Parametrization",fPtParaFunc,fPtMin,fPtMax,0);
158// Set representation precision to 10 MeV
159 Int_t npx= Int_t((fPtMax-fPtMin)/fDeltaPt);
160
161 fPtPara->SetNpx(npx);
162
163 fYPara = new TF1("Y -Parametrization",fYParaFunc,fYMin,fYMax,0);
164 TF1* ptPara = new TF1("Pt-Parametrization",fPtParaFunc,0,15,0);
165 TF1* yPara = new TF1("Y -Parametrization",fYParaFunc,-6,6,0);
b7601ac4 166
fe4da5cc 167//
168// dN/dy| y=0
749070b6 169 Double_t y1=0;
170 Double_t y2=0;
171
172 fdNdy0=fYParaFunc(&y1,&y2);
fe4da5cc 173//
174// Integral over generation region
749070b6 175 Float_t intYS = yPara ->Integral(fYMin, fYMax);
176 Float_t intPt0 = ptPara->Integral(0,15);
177 Float_t intPtS = ptPara->Integral(fPtMin,fPtMax);
178 Float_t phiWgt=(fPhiMax-fPhiMin)/2./TMath::Pi();
179 if (fAnalog == analog) {
180 fYWgt = intYS/fdNdy0;
181 fPtWgt = intPtS/intPt0;
182 fParentWeight = fYWgt*fPtWgt*phiWgt/fNpart;
183 } else {
184 fYWgt = intYS/fdNdy0;
185 fPtWgt = (fPtMax-fPtMin)/intPt0;
186 fParentWeight = fYWgt*fPtWgt*phiWgt/fNpart;
187 }
fe4da5cc 188//
189// particle decay related initialization
749070b6 190 fPythia->DefineParticles();
fe4da5cc 191// semimuonic decays of charm and beauty
749070b6 192 fPythia->ForceDecay(fForceDecay);
fe4da5cc 193//
194 switch (fForceDecay)
195 {
196 case semielectronic:
197 case dielectron:
198 case b_jpsi_dielectron:
199 case b_psip_dielectron:
200 fChildSelect[0]=11;
201 break;
202 case semimuonic:
203 case dimuon:
204 case b_jpsi_dimuon:
205 case b_psip_dimuon:
206 fChildSelect[0]=13;
207 break;
b7601ac4 208 case pitomu:
209 fChildSelect[0]=13;
210 break;
211 case katomu:
212 fChildSelect[0]=13;
213 break;
886b6f73 214 case nodecay:
215 break;
216 case all:
217 break;
fe4da5cc 218 }
fe4da5cc 219}
220
221//____________________________________________________________
222void AliGenParam::Generate()
223{
28337bc1 224//
225// Generate 'npart' of light and heavy mesons (J/Psi, upsilon or phi, Pion,
226// Kaons, Etas, Omegas) and Baryons (proton, antiprotons, neutrons and
227// antineutrons in the the desired theta, phi and momentum windows;
228// Gaussian smearing on the vertex is done if selected.
cc5d764c 229// The decay of heavy mesons is done using lujet,
230// and the childern particle are tracked by GEANT
231// However, light mesons are directly tracked by GEANT
232// setting fForceDecay = nodecay (SetForceDecay(nodecay))
28337bc1 233//
fe4da5cc 234
21aaa175 235
28337bc1 236 Float_t polar[3]= {0,0,0}; // Polarisation of the parent particle (for GEANT tracking)
237 Float_t origin0[3]; // Origin of the generated parent particle (for GEANT tracking)
238 Float_t pt, pl, ptot; // Transverse, logitudinal and total momenta of the parent particle
239 Float_t phi, theta; // Phi and theta spherical angles of the parent particle momentum
240 Float_t p[3], pc[3],
241 och[3], pch[10][3]; // Momentum, polarisation and origin of the children particles from lujet
fe4da5cc 242 Float_t ty, xmt;
21aaa175 243 Int_t nt, i, j, kfch[10];
fe4da5cc 244 Float_t wgtp, wgtch;
245 Double_t dummy;
09fd3ea2 246 static TClonesArray *particles;
fe4da5cc 247 //
09fd3ea2 248 if(!particles) particles=new TClonesArray("TParticle",1000);
fe4da5cc 249 //
250 Float_t random[6];
28337bc1 251
252// Calculating vertex position per event
fe4da5cc 253 for (j=0;j<3;j++) origin0[j]=fOrigin[j];
254 if(fVertexSmear==perEvent) {
cfce8870 255 gMC->Rndm(random,6);
fe4da5cc 256 for (j=0;j<3;j++) {
257 origin0[j]+=fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
258 TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
259 }
260 }
21aaa175 261 Int_t ipa=0;
28337bc1 262// Generating fNpart particles
21aaa175 263 while (ipa<fNpart) {
cc5d764c 264 while(1) {
fe4da5cc 265//
266// particle type
749070b6 267 Int_t iPart = fIpParaFunc();
268 fChildWeight=(fPythia->GetBraPart(iPart))*fParentWeight;
269 Float_t am=fPythia->GetPMAS(fPythia->Lucomp(iPart),1);
cfce8870 270 gMC->Rndm(random,2);
fe4da5cc 271//
272// phi
273 phi=fPhiMin+random[0]*(fPhiMax-fPhiMin);
274//
275// y
276 ty=Float_t(TMath::TanH(fYPara->GetRandom()));
277//
278// pT
82db6e43 279 if (fAnalog == analog) {
fe4da5cc 280 pt=fPtPara->GetRandom();
281 wgtp=fParentWeight;
282 wgtch=fChildWeight;
283 } else {
284 pt=fPtMin+random[1]*(fPtMax-fPtMin);
285 Double_t ptd=pt;
286 wgtp=fParentWeight*fPtParaFunc(& ptd, &dummy);
287 wgtch=fChildWeight*fPtParaFunc(& ptd, &dummy);
288 }
289 xmt=sqrt(pt*pt+am*am);
290 pl=xmt*ty/sqrt(1.-ty*ty);
291 theta=TMath::ATan2(pt,pl);
cc5d764c 292// Cut on theta
fe4da5cc 293 if(theta<fThetaMin || theta>fThetaMax) continue;
294 ptot=TMath::Sqrt(pt*pt+pl*pl);
cc5d764c 295// Cut on momentum
fe4da5cc 296 if(ptot<fPMin || ptot>fPMax) continue;
297 p[0]=pt*TMath::Cos(phi);
298 p[1]=pt*TMath::Sin(phi);
299 p[2]=pl;
300 if(fVertexSmear==perTrack) {
cfce8870 301 gMC->Rndm(random,6);
fe4da5cc 302 for (j=0;j<3;j++) {
303 origin0[j]=
304 fOrigin[j]+fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
305 TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
306 }
307 }
28337bc1 308
309// Looking at fForceDecay :
cc5d764c 310// if fForceDecay != none Primary particle decays using
311// AliPythia and children are tracked by GEANT
28337bc1 312//
cc5d764c 313// if fForceDecay == none Primary particle is tracked by GEANT
314// (In the latest, make sure that GEANT actually does all the decays you want)
fe4da5cc 315//
886b6f73 316 if (fForceDecay != nodecay) {
28337bc1 317// Using lujet to decay particle
886b6f73 318 Float_t energy=TMath::Sqrt(ptot*ptot+am*am);
749070b6 319 fPythia->DecayParticle(iPart,energy,theta,phi);
fe4da5cc 320//
cc5d764c 321// select decay particles
886b6f73 322 Int_t np=fPythia->ImportParticles(particles,"All");
886b6f73 323 Int_t ncsel=0;
324 for (i = 1; i<np; i++) {
325 TParticle * iparticle = (TParticle *) particles->At(i);
326 Int_t kf = iparticle->GetPdgCode();
fe4da5cc 327//
328// children
886b6f73 329 if (ChildSelected(TMath::Abs(kf)))
330 {
331 pc[0]=iparticle->Px();
332 pc[1]=iparticle->Py();
333 pc[2]=iparticle->Pz();
334 och[0]=origin0[0]+iparticle->Vx()/10;
335 och[1]=origin0[1]+iparticle->Vy()/10;
336 och[2]=origin0[2]+iparticle->Vz()/10;
337 if (fCutOnChild) {
749070b6 338 Float_t ptChild=TMath::Sqrt(pc[0]*pc[0]+pc[1]*pc[1]);
339 Float_t pChild=TMath::Sqrt(ptChild*ptChild+pc[2]*pc[2]);
340 Float_t thetaChild=TMath::ATan2(ptChild,pc[2]);
341 Float_t phiChild=TMath::ATan2(pc[1],pc[0]);
886b6f73 342 Bool_t childok =
749070b6 343 ((ptChild > fChildPtMin && ptChild <fChildPtMax) &&
344 (pChild > fChildPMin && pChild <fChildPMax) &&
345 (thetaChild > fChildThetaMin && thetaChild <fChildThetaMax) &&
346 (phiChild > fChildPhiMin && phiChild <fChildPhiMax));
886b6f73 347 if(childok)
348 {
349 pch[ncsel][0]=pc[0];
350 pch[ncsel][1]=pc[1];
351 pch[ncsel][2]=pc[2];
352 kfch[ncsel]=kf;
353 ncsel++;
354 } else {
355 ncsel=-1;
356 break;
357 } // child kine cuts
21aaa175 358 } else {
886b6f73 359 pch[ncsel][0]=pc[0];
360 pch[ncsel][1]=pc[1];
361 pch[ncsel][2]=pc[2];
362 kfch[ncsel]=kf;
363 ncsel++;
364 } // if child selection
365 } // select muon
366 } // decay particle loop
367 Int_t iparent;
368 if ((fCutOnChild && ncsel >0) || !fCutOnChild){
369 ipa++;
21aaa175 370//
371// parent
886b6f73 372 gAlice->
749070b6 373 SetTrack(0,-1,iPart,p,origin0,polar,0,"Primary",nt,wgtp);
886b6f73 374 iparent=nt;
f87cfe57 375 gAlice->KeepTrack(nt);
886b6f73 376 for (i=0; i< ncsel; i++) {
377 gAlice->SetTrack(fTrackIt,iparent,kfch[i],
378 &pch[i][0],och,polar,
379 0,"Decay",nt,wgtch);
380 gAlice->KeepTrack(nt);
381 }
28337bc1 382 } // Decays by Lujet
21aaa175 383 } // kinematic selection
28337bc1 384 else // nodecay option, so parent will be tracked by GEANT (pions, kaons, eta, omegas, baryons)
385 {
386 gAlice->
749070b6 387 SetTrack(fTrackIt,-1,iPart,p,origin0,polar,0,"Primary",nt,wgtp);
28337bc1 388 ipa++;
389 }
fe4da5cc 390 break;
21aaa175 391 } // while
fe4da5cc 392 } // event loop
393}
394
395Bool_t AliGenParam::ChildSelected(Int_t ip)
396{
749070b6 397// True if particle is in list of selected children
fe4da5cc 398 for (Int_t i=0; i<5; i++)
399 {
400 if (fChildSelect[i]==ip) return kTRUE;
401 }
402 return kFALSE;
403}
404
1578254f 405Bool_t AliGenParam::KinematicSelection(TParticle *particle)
fe4da5cc 406{
749070b6 407// Perform kinematic cuts
1578254f 408 Float_t px=particle->Px();
409 Float_t py=particle->Py();
410 Float_t pz=particle->Pz();
fe4da5cc 411//
412// momentum cut
413 Float_t p=TMath::Sqrt(px*px+py*py+pz*pz);
414 if (p > fPMax || p < fPMin)
415 {
416// printf("\n failed p cut %f %f %f \n",p,fPMin,fPMax);
417 return kFALSE;
418 }
419 Float_t pt=TMath::Sqrt(px*px+py*py);
420
421//
422// theta cut
423 Float_t theta = Float_t(TMath::ATan2(Double_t(pt),Double_t(p)));
424 if (theta > fThetaMax || theta < fThetaMin)
425 {
426// printf("\n failed theta cut %f %f %f \n",theta,fThetaMin,fThetaMax);
427 return kFALSE;
428 }
429
430 return kTRUE;
431}
432
433
f87cfe57 434AliGenParam& AliGenParam::operator=(const AliGenParam& rhs)
435{
436// Assignment operator
437 return *this;
438}
439
fe4da5cc 440
441