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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 | ||
88cb7938 | 16 | /* $Id$ */ |
6d4dd317 | 17 | |
18 | // Class to generate particles from using paramtrized pT and y distributions. | |
19 | // Distributions are obtained from pointer to object of type AliGenLib. | |
20 | // (For example AliGenMUONlib) | |
21 | // Decays are performed using Pythia. | |
22 | // andreas.morsch@cern.ch | |
23 | ||
fe4da5cc | 24 | #include "AliGenParam.h" |
2904363f | 25 | #include "AliDecayer.h" |
fe4da5cc | 26 | #include "AliGenMUONlib.h" |
27 | #include "AliRun.h" | |
1578254f | 28 | #include <TParticle.h> |
fa480368 | 29 | #include <TParticlePDG.h> |
30 | #include <TDatabasePDG.h> | |
31 | #include <TLorentzVector.h> | |
32 | ||
f87cfe57 | 33 | #include <TF1.h> |
5bd39445 | 34 | #include <TCanvas.h> |
35 | #include <TH1.h> | |
fe4da5cc | 36 | |
37 | ClassImp(AliGenParam) | |
38 | ||
39 | //------------------------------------------------------------ | |
40 | ||
41 | //Begin_Html | |
42 | /* | |
1439f98e | 43 | <img src="picts/AliGenParam.gif"> |
fe4da5cc | 44 | */ |
45 | //End_Html | |
46 | ||
47 | //____________________________________________________________ | |
48 | //____________________________________________________________ | |
49 | AliGenParam::AliGenParam() | |
fe4da5cc | 50 | { |
b22ee262 | 51 | // Deafault constructor |
52 | fPtPara = 0; | |
53 | fYPara = 0; | |
34f60c01 | 54 | fParam = 0; |
55 | fAnalog = kAnalog; | |
b22ee262 | 56 | SetDeltaPt(); |
2685bf00 | 57 | fDecayer = 0; |
8b31bfac | 58 | |
59 | ||
b22ee262 | 60 | } |
61 | ||
fff02fee | 62 | AliGenParam::AliGenParam(Int_t npart, AliGenLib * Library, Int_t param, char* tname):AliGenMC(npart) |
b22ee262 | 63 | { |
64 | // Constructor using number of particles parameterisation id and library | |
8b31bfac | 65 | fName = "Param"; |
66 | fTitle= "Particle Generator using pT and y parameterisation"; | |
b22ee262 | 67 | |
68 | fPtParaFunc = Library->GetPt(param, tname); | |
69 | fYParaFunc = Library->GetY (param, tname); | |
70 | fIpParaFunc = Library->GetIp(param, tname); | |
71 | ||
72 | fPtPara = 0; | |
73 | fYPara = 0; | |
74 | fParam = param; | |
34f60c01 | 75 | fAnalog = kAnalog; |
b22ee262 | 76 | SetForceDecay(); |
b22ee262 | 77 | SetDeltaPt(); |
fe4da5cc | 78 | } |
79 | ||
80 | //____________________________________________________________ | |
886b6f73 | 81 | |
fff02fee | 82 | AliGenParam::AliGenParam(Int_t npart, Int_t param, char* tname):AliGenMC(npart) |
fe4da5cc | 83 | { |
b22ee262 | 84 | // Constructor using parameterisation id and number of particles |
8b31bfac | 85 | // |
86 | fName = "Param"; | |
87 | fTitle= "Particle Generator using pT and y parameterisation"; | |
88 | ||
675e9664 | 89 | AliGenLib* pLibrary = new AliGenMUONlib(); |
b22ee262 | 90 | |
675e9664 | 91 | fPtParaFunc = pLibrary->GetPt(param, tname); |
92 | fYParaFunc = pLibrary->GetY (param, tname); | |
93 | fIpParaFunc = pLibrary->GetIp(param, tname); | |
b22ee262 | 94 | |
95 | fPtPara = 0; | |
96 | fYPara = 0; | |
97 | fParam = param; | |
34f60c01 | 98 | fAnalog = kAnalog; |
b22ee262 | 99 | fChildSelect.Set(5); |
100 | for (Int_t i=0; i<5; i++) fChildSelect[i]=0; | |
101 | SetForceDecay(); | |
102 | SetCutOnChild(); | |
103 | SetChildMomentumRange(); | |
104 | SetChildPtRange(); | |
105 | SetChildPhiRange(); | |
106 | SetChildThetaRange(); | |
107 | SetDeltaPt(); | |
fe4da5cc | 108 | } |
109 | ||
34f60c01 | 110 | AliGenParam::AliGenParam(Int_t npart, Int_t param, |
886b6f73 | 111 | Double_t (*PtPara) (Double_t*, Double_t*), |
112 | Double_t (*YPara ) (Double_t* ,Double_t*), | |
65fb704d | 113 | Int_t (*IpPara) (TRandom *)) |
fff02fee | 114 | :AliGenMC(npart) |
886b6f73 | 115 | { |
749070b6 | 116 | // Constructor |
28337bc1 | 117 | // Gines Martinez 1/10/99 |
8b31bfac | 118 | fName = "Param"; |
119 | fTitle= "Particle Generator using pT and y parameterisation"; | |
120 | ||
886b6f73 | 121 | fPtParaFunc = PtPara; |
122 | fYParaFunc = YPara; | |
123 | fIpParaFunc = IpPara; | |
28337bc1 | 124 | // |
886b6f73 | 125 | fPtPara = 0; |
126 | fYPara = 0; | |
127 | fParam = param; | |
34f60c01 | 128 | fAnalog = kAnalog; |
886b6f73 | 129 | fChildSelect.Set(5); |
130 | for (Int_t i=0; i<5; i++) fChildSelect[i]=0; | |
131 | SetForceDecay(); | |
132 | SetCutOnChild(); | |
749070b6 | 133 | SetChildMomentumRange(); |
134 | SetChildPtRange(); | |
135 | SetChildPhiRange(); | |
136 | SetChildThetaRange(); | |
137 | SetDeltaPt(); | |
886b6f73 | 138 | } |
139 | ||
f87cfe57 | 140 | |
6d4dd317 | 141 | AliGenParam::AliGenParam(const AliGenParam & Param) |
f87cfe57 | 142 | { |
143 | // copy constructor | |
6d4dd317 | 144 | Param.Copy(*this); |
f87cfe57 | 145 | } |
146 | ||
fe4da5cc | 147 | //____________________________________________________________ |
148 | AliGenParam::~AliGenParam() | |
149 | { | |
749070b6 | 150 | // Destructor |
fe4da5cc | 151 | delete fPtPara; |
152 | delete fYPara; | |
153 | } | |
154 | ||
155 | //____________________________________________________________ | |
156 | void AliGenParam::Init() | |
157 | { | |
749070b6 | 158 | // Initialisation |
fa480368 | 159 | |
2904363f | 160 | if (gMC) fDecayer = gMC->GetDecayer(); |
fe4da5cc | 161 | //Begin_Html |
162 | /* | |
1439f98e | 163 | <img src="picts/AliGenParam.gif"> |
fe4da5cc | 164 | */ |
165 | //End_Html | |
166 | ||
749070b6 | 167 | fPtPara = new TF1("Pt-Parametrization",fPtParaFunc,fPtMin,fPtMax,0); |
168 | // Set representation precision to 10 MeV | |
169 | Int_t npx= Int_t((fPtMax-fPtMin)/fDeltaPt); | |
170 | ||
171 | fPtPara->SetNpx(npx); | |
172 | ||
173 | fYPara = new TF1("Y -Parametrization",fYParaFunc,fYMin,fYMax,0); | |
174 | TF1* ptPara = new TF1("Pt-Parametrization",fPtParaFunc,0,15,0); | |
175 | TF1* yPara = new TF1("Y -Parametrization",fYParaFunc,-6,6,0); | |
b7601ac4 | 176 | |
fe4da5cc | 177 | // |
178 | // dN/dy| y=0 | |
749070b6 | 179 | Double_t y1=0; |
180 | Double_t y2=0; | |
181 | ||
182 | fdNdy0=fYParaFunc(&y1,&y2); | |
fe4da5cc | 183 | // |
184 | // Integral over generation region | |
749070b6 | 185 | Float_t intYS = yPara ->Integral(fYMin, fYMax); |
186 | Float_t intPt0 = ptPara->Integral(0,15); | |
187 | Float_t intPtS = ptPara->Integral(fPtMin,fPtMax); | |
188 | Float_t phiWgt=(fPhiMax-fPhiMin)/2./TMath::Pi(); | |
34f60c01 | 189 | if (fAnalog == kAnalog) { |
749070b6 | 190 | fYWgt = intYS/fdNdy0; |
191 | fPtWgt = intPtS/intPt0; | |
192 | fParentWeight = fYWgt*fPtWgt*phiWgt/fNpart; | |
193 | } else { | |
194 | fYWgt = intYS/fdNdy0; | |
195 | fPtWgt = (fPtMax-fPtMin)/intPt0; | |
196 | fParentWeight = fYWgt*fPtWgt*phiWgt/fNpart; | |
197 | } | |
fe4da5cc | 198 | // |
199 | // particle decay related initialization | |
00d6ce7d | 200 | fDecayer->SetForceDecay(fForceDecay); |
fa480368 | 201 | fDecayer->Init(); |
00d6ce7d | 202 | |
fe4da5cc | 203 | // |
fff02fee | 204 | AliGenMC::Init(); |
fe4da5cc | 205 | } |
206 | ||
207 | //____________________________________________________________ | |
208 | void AliGenParam::Generate() | |
209 | { | |
28337bc1 | 210 | // |
211 | // Generate 'npart' of light and heavy mesons (J/Psi, upsilon or phi, Pion, | |
212 | // Kaons, Etas, Omegas) and Baryons (proton, antiprotons, neutrons and | |
213 | // antineutrons in the the desired theta, phi and momentum windows; | |
214 | // Gaussian smearing on the vertex is done if selected. | |
cc5d764c | 215 | // The decay of heavy mesons is done using lujet, |
216 | // and the childern particle are tracked by GEANT | |
217 | // However, light mesons are directly tracked by GEANT | |
218 | // setting fForceDecay = nodecay (SetForceDecay(nodecay)) | |
28337bc1 | 219 | // |
771bbe45 | 220 | // |
221 | // Reinitialize decayer | |
222 | fDecayer->Init(); | |
223 | // | |
28337bc1 | 224 | Float_t polar[3]= {0,0,0}; // Polarisation of the parent particle (for GEANT tracking) |
225 | Float_t origin0[3]; // Origin of the generated parent particle (for GEANT tracking) | |
226 | Float_t pt, pl, ptot; // Transverse, logitudinal and total momenta of the parent particle | |
227 | Float_t phi, theta; // Phi and theta spherical angles of the parent particle momentum | |
228 | Float_t p[3], pc[3], | |
fff02fee | 229 | och[3]; // Momentum, polarisation and origin of the children particles from lujet |
2d7a47be | 230 | Double_t ty, xmt; |
fff02fee | 231 | Int_t nt, i, j; |
fe4da5cc | 232 | Float_t wgtp, wgtch; |
233 | Double_t dummy; | |
09fd3ea2 | 234 | static TClonesArray *particles; |
fe4da5cc | 235 | // |
fff02fee | 236 | if(!particles) particles = new TClonesArray("TParticle",1000); |
8b31bfac | 237 | |
349be858 | 238 | TDatabasePDG *pDataBase = TDatabasePDG::Instance(); |
fe4da5cc | 239 | // |
240 | Float_t random[6]; | |
28337bc1 | 241 | |
242 | // Calculating vertex position per event | |
fe4da5cc | 243 | for (j=0;j<3;j++) origin0[j]=fOrigin[j]; |
aee8290b | 244 | if(fVertexSmear==kPerEvent) { |
d9ea0e3b | 245 | Vertex(); |
246 | for (j=0;j<3;j++) origin0[j]=fVertex[j]; | |
fe4da5cc | 247 | } |
d9ea0e3b | 248 | |
21aaa175 | 249 | Int_t ipa=0; |
fff02fee | 250 | |
28337bc1 | 251 | // Generating fNpart particles |
21aaa175 | 252 | while (ipa<fNpart) { |
cc5d764c | 253 | while(1) { |
fe4da5cc | 254 | // |
255 | // particle type | |
65fb704d | 256 | Int_t iPart = fIpParaFunc(fRandom); |
fa480368 | 257 | fChildWeight=(fDecayer->GetPartialBranchingRatio(iPart))*fParentWeight; |
675e9664 | 258 | TParticlePDG *particle = pDataBase->GetParticle(iPart); |
fa480368 | 259 | Float_t am = particle->Mass(); |
8b31bfac | 260 | |
65fb704d | 261 | Rndm(random,2); |
fe4da5cc | 262 | // |
263 | // phi | |
264 | phi=fPhiMin+random[0]*(fPhiMax-fPhiMin); | |
265 | // | |
266 | // y | |
2d7a47be | 267 | ty = TMath::TanH(fYPara->GetRandom()); |
fe4da5cc | 268 | // |
269 | // pT | |
34f60c01 | 270 | if (fAnalog == kAnalog) { |
fe4da5cc | 271 | pt=fPtPara->GetRandom(); |
272 | wgtp=fParentWeight; | |
273 | wgtch=fChildWeight; | |
274 | } else { | |
275 | pt=fPtMin+random[1]*(fPtMax-fPtMin); | |
276 | Double_t ptd=pt; | |
277 | wgtp=fParentWeight*fPtParaFunc(& ptd, &dummy); | |
278 | wgtch=fChildWeight*fPtParaFunc(& ptd, &dummy); | |
279 | } | |
280 | xmt=sqrt(pt*pt+am*am); | |
2d7a47be | 281 | if (TMath::Abs(ty)==1.) { |
282 | ty=0.; | |
283 | Fatal("AliGenParam", | |
284 | "Division by 0: Please check you rapidity range !"); | |
285 | } | |
286 | ||
fe4da5cc | 287 | pl=xmt*ty/sqrt(1.-ty*ty); |
288 | theta=TMath::ATan2(pt,pl); | |
cc5d764c | 289 | // Cut on theta |
fe4da5cc | 290 | if(theta<fThetaMin || theta>fThetaMax) continue; |
291 | ptot=TMath::Sqrt(pt*pt+pl*pl); | |
cc5d764c | 292 | // Cut on momentum |
fe4da5cc | 293 | if(ptot<fPMin || ptot>fPMax) continue; |
fff02fee | 294 | // |
fe4da5cc | 295 | p[0]=pt*TMath::Cos(phi); |
296 | p[1]=pt*TMath::Sin(phi); | |
297 | p[2]=pl; | |
aee8290b | 298 | if(fVertexSmear==kPerTrack) { |
65fb704d | 299 | Rndm(random,6); |
fe4da5cc | 300 | for (j=0;j<3;j++) { |
301 | origin0[j]= | |
302 | fOrigin[j]+fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())* | |
303 | TMath::Sqrt(-2*TMath::Log(random[2*j+1])); | |
304 | } | |
305 | } | |
28337bc1 | 306 | |
307 | // Looking at fForceDecay : | |
cc5d764c | 308 | // if fForceDecay != none Primary particle decays using |
309 | // AliPythia and children are tracked by GEANT | |
28337bc1 | 310 | // |
cc5d764c | 311 | // if fForceDecay == none Primary particle is tracked by GEANT |
312 | // (In the latest, make sure that GEANT actually does all the decays you want) | |
fe4da5cc | 313 | // |
fff02fee | 314 | |
34f60c01 | 315 | if (fForceDecay != kNoDecay) { |
28337bc1 | 316 | // Using lujet to decay particle |
886b6f73 | 317 | Float_t energy=TMath::Sqrt(ptot*ptot+am*am); |
fa480368 | 318 | TLorentzVector pmom(p[0], p[1], p[2], energy); |
319 | fDecayer->Decay(iPart,&pmom); | |
fe4da5cc | 320 | // |
cc5d764c | 321 | // select decay particles |
fa480368 | 322 | Int_t np=fDecayer->ImportParticles(particles); |
1242532d | 323 | |
324 | // Selecting GeometryAcceptance for particles fPdgCodeParticleforAcceptanceCut; | |
325 | if (fGeometryAcceptance) | |
326 | if (!CheckAcceptanceGeometry(np,particles)) continue; | |
886b6f73 | 327 | Int_t ncsel=0; |
fff02fee | 328 | Int_t* pFlag = new Int_t[np]; |
329 | Int_t* pParent = new Int_t[np]; | |
330 | Int_t* pSelected = new Int_t[np]; | |
331 | Int_t* trackIt = new Int_t[np]; | |
332 | ||
333 | for (i=0; i<np; i++) { | |
334 | pFlag[i] = 0; | |
335 | pSelected[i] = 0; | |
336 | pParent[i] = -1; | |
337 | } | |
338 | ||
6ba00c52 | 339 | if (np >1) { |
340 | TParticle* iparticle = (TParticle *) particles->At(0); | |
fff02fee | 341 | Int_t ipF, ipL; |
342 | for (i = 1; i<np ; i++) { | |
343 | trackIt[i] = 1; | |
6ba00c52 | 344 | iparticle = (TParticle *) particles->At(i); |
345 | Int_t kf = iparticle->GetPdgCode(); | |
fff02fee | 346 | Int_t ks = iparticle->GetStatusCode(); |
347 | // flagged particle | |
348 | ||
349 | if (pFlag[i] == 1) { | |
fff02fee | 350 | ipF = iparticle->GetFirstDaughter(); |
351 | ipL = iparticle->GetLastDaughter(); | |
352 | if (ipF > 0) for (j=ipF-1; j<ipL; j++) pFlag[j]=1; | |
353 | continue; | |
354 | } | |
355 | ||
356 | // flag decay products of particles with long life-time (c tau > .3 mum) | |
357 | ||
358 | if (ks != 1) { | |
2d7a47be | 359 | // TParticlePDG *particle = pDataBase->GetParticle(kf); |
fff02fee | 360 | |
361 | Double_t lifeTime = fDecayer->GetLifetime(kf); | |
2d7a47be | 362 | // Double_t mass = particle->Mass(); |
363 | // Double_t width = particle->Width(); | |
47fc6bd5 | 364 | if (lifeTime > (Double_t) fMaxLifeTime) { |
fff02fee | 365 | ipF = iparticle->GetFirstDaughter(); |
366 | ipL = iparticle->GetLastDaughter(); | |
367 | if (ipF > 0) for (j=ipF-1; j<ipL; j++) pFlag[j]=1; | |
368 | } else{ | |
369 | trackIt[i] = 0; | |
370 | pSelected[i] = 1; | |
371 | } | |
372 | } // ks==1 ? | |
fe4da5cc | 373 | // |
374 | // children | |
47fc6bd5 | 375 | |
fff02fee | 376 | if (ChildSelected(TMath::Abs(kf)) || fForceDecay == kAll && trackIt[i]) |
6ba00c52 | 377 | { |
6ba00c52 | 378 | if (fCutOnChild) { |
fff02fee | 379 | pc[0]=iparticle->Px(); |
380 | pc[1]=iparticle->Py(); | |
381 | pc[2]=iparticle->Pz(); | |
382 | Bool_t childok = KinematicSelection(iparticle, 1); | |
383 | if(childok) { | |
384 | pSelected[i] = 1; | |
6ba00c52 | 385 | ncsel++; |
386 | } else { | |
387 | ncsel=-1; | |
388 | break; | |
389 | } // child kine cuts | |
390 | } else { | |
fff02fee | 391 | pSelected[i] = 1; |
886b6f73 | 392 | ncsel++; |
6ba00c52 | 393 | } // if child selection |
394 | } // select muon | |
395 | } // decay particle loop | |
396 | } // if decay products | |
397 | ||
886b6f73 | 398 | Int_t iparent; |
399 | if ((fCutOnChild && ncsel >0) || !fCutOnChild){ | |
400 | ipa++; | |
21aaa175 | 401 | // |
fff02fee | 402 | // Parent |
a99cf51f | 403 | SetTrack(0, -1, iPart, p, origin0, polar, 0, kPPrimary, nt, wgtp); |
fff02fee | 404 | pParent[0] = nt; |
a99cf51f | 405 | KeepTrack(nt); |
fff02fee | 406 | // |
407 | // Decay Products | |
408 | // | |
409 | for (i = 1; i < np; i++) { | |
410 | if (pSelected[i]) { | |
411 | TParticle* iparticle = (TParticle *) particles->At(i); | |
412 | Int_t kf = iparticle->GetPdgCode(); | |
413 | Int_t ipa = iparticle->GetFirstMother()-1; | |
414 | ||
415 | och[0] = origin0[0]+iparticle->Vx()/10; | |
416 | och[1] = origin0[1]+iparticle->Vy()/10; | |
417 | och[2] = origin0[2]+iparticle->Vz()/10; | |
418 | pc[0] = iparticle->Px(); | |
419 | pc[1] = iparticle->Py(); | |
420 | pc[2] = iparticle->Pz(); | |
421 | ||
422 | if (ipa > -1) { | |
423 | iparent = pParent[ipa]; | |
424 | } else { | |
425 | iparent = -1; | |
426 | } | |
1242532d | 427 | |
a99cf51f | 428 | SetTrack(fTrackIt*trackIt[i], iparent, kf, |
fff02fee | 429 | pc, och, polar, |
430 | 0, kPDecay, nt, wgtch); | |
431 | pParent[i] = nt; | |
a99cf51f | 432 | KeepTrack(nt); |
8b31bfac | 433 | } // Selected |
434 | } // Particle loop | |
28337bc1 | 435 | } // Decays by Lujet |
8b31bfac | 436 | particles->Clear(); |
fff02fee | 437 | if (pFlag) delete[] pFlag; |
438 | if (pParent) delete[] pParent; | |
439 | if (pSelected) delete[] pSelected; | |
8b31bfac | 440 | if (trackIt) delete[] trackIt; |
21aaa175 | 441 | } // kinematic selection |
28337bc1 | 442 | else // nodecay option, so parent will be tracked by GEANT (pions, kaons, eta, omegas, baryons) |
443 | { | |
444 | gAlice-> | |
65fb704d | 445 | SetTrack(fTrackIt,-1,iPart,p,origin0,polar,0,kPPrimary,nt,wgtp); |
28337bc1 | 446 | ipa++; |
447 | } | |
fe4da5cc | 448 | break; |
21aaa175 | 449 | } // while |
fe4da5cc | 450 | } // event loop |
a99cf51f | 451 | SetHighWaterMark(nt); |
fe4da5cc | 452 | } |
453 | ||
5bd39445 | 454 | void AliGenParam::Draw() |
455 | { | |
456 | // | |
457 | // Draw the pT and y Distributions | |
458 | // | |
459 | TCanvas *c0 = new TCanvas("c0","Canvas 0",400,10,600,700); | |
460 | c0->Divide(2,1); | |
461 | c0->cd(1); | |
462 | fPtPara->Draw(); | |
463 | fPtPara->GetHistogram()->SetXTitle("p_{T} (GeV)"); | |
464 | c0->cd(2); | |
465 | fYPara->Draw(); | |
466 | fYPara->GetHistogram()->SetXTitle("y"); | |
467 | } | |
468 | ||
f87cfe57 | 469 | AliGenParam& AliGenParam::operator=(const AliGenParam& rhs) |
470 | { | |
471 | // Assignment operator | |
472 | return *this; | |
473 | } | |
474 | ||
fe4da5cc | 475 | |
476 |