]>
Commit | Line | Data |
---|---|---|
e36044d6 | 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 | /* $Id$ */ |
e36044d6 | 17 | |
62d0ae06 | 18 | // Base class for generators using external MC generators. |
19 | // For example AliGenPythia using Pythia. | |
20 | // Provides basic functionality: setting of kinematic cuts on | |
21 | // decay products and particle selection. | |
22 | // andreas.morsch@cern.ch | |
23 | ||
ac3faee4 | 24 | #include <TClonesArray.h> |
65de9f86 | 25 | #include <TMath.h> |
116cbefd | 26 | #include <TPDGCode.h> |
e36044d6 | 27 | #include <TParticle.h> |
7eb751fe | 28 | #include <TLorentzVector.h> |
29 | #include <TVector3.h> | |
e36044d6 | 30 | |
116cbefd | 31 | #include "AliGenMC.h" |
e052713d | 32 | #include "AliGenEventHeader.h" |
d97fb2bb | 33 | #include "AliRun.h" |
ac3faee4 | 34 | #include "AliGeometry.h" |
4a33c50d | 35 | #include "AliDecayer.h" |
116cbefd | 36 | |
198bb1c7 | 37 | ClassImp(AliGenMC) |
e36044d6 | 38 | |
39 | AliGenMC::AliGenMC() | |
1c56e311 | 40 | :AliGenerator(), |
969a210b | 41 | fParticles("TParticle", 1000), |
1c56e311 | 42 | fParentSelect(8), |
43 | fChildSelect(8), | |
44 | fCutOnChild(0), | |
45 | fChildPtMin(0.), | |
46 | fChildPtMax(1.e10), | |
47 | fChildPMin(0.), | |
48 | fChildPMax(1.e10), | |
49 | fChildPhiMin(0.), | |
50 | fChildPhiMax(2. * TMath::Pi()), | |
51 | fChildThetaMin(0.), | |
52 | fChildThetaMax(TMath::Pi()), | |
53 | fChildYMin(-12.), | |
54 | fChildYMax(12.), | |
55 | fXingAngleX(0.), | |
56 | fXingAngleY(0.), | |
57 | fForceDecay(kAll), | |
58 | fMaxLifeTime(1.e-15), | |
1c56e311 | 59 | fDyBoost(0.), |
60 | fGeometryAcceptance(0), | |
61 | fPdgCodeParticleforAcceptanceCut(0), | |
d97fb2bb | 62 | fNumberOfAcceptedParticles(0), |
e7c989e4 | 63 | fNprimaries(0) |
e36044d6 | 64 | { |
65 | // Default Constructor | |
e7c989e4 | 66 | fAProjectile = 1; |
67 | fZProjectile = 1; | |
68 | fATarget = 1; | |
69 | fZTarget = 1; | |
70 | fProjectile = "P"; | |
71 | fTarget = "P"; | |
e36044d6 | 72 | } |
73 | ||
74 | AliGenMC::AliGenMC(Int_t npart) | |
1c56e311 | 75 | :AliGenerator(npart), |
ea24f998 | 76 | fParticles("TParticle", 1000), |
1c56e311 | 77 | fParentSelect(8), |
78 | fChildSelect(8), | |
79 | fCutOnChild(0), | |
80 | fChildPtMin(0.), | |
81 | fChildPtMax(1.e10), | |
82 | fChildPMin(0.), | |
83 | fChildPMax(1.e10), | |
84 | fChildPhiMin(0.), | |
85 | fChildPhiMax(2. * TMath::Pi()), | |
86 | fChildThetaMin(0.), | |
87 | fChildThetaMax(TMath::Pi()), | |
88 | fChildYMin(-12.), | |
89 | fChildYMax(12.), | |
90 | fXingAngleX(0.), | |
91 | fXingAngleY(0.), | |
92 | fForceDecay(kAll), | |
93 | fMaxLifeTime(1.e-15), | |
1c56e311 | 94 | fDyBoost(0.), |
95 | fGeometryAcceptance(0), | |
96 | fPdgCodeParticleforAcceptanceCut(0), | |
d97fb2bb | 97 | fNumberOfAcceptedParticles(0), |
e7c989e4 | 98 | fNprimaries(0) |
e36044d6 | 99 | { |
100 | // Constructor | |
e36044d6 | 101 | // |
e7c989e4 | 102 | fAProjectile = 1; |
103 | fZProjectile = 1; | |
104 | fATarget = 1; | |
105 | fZTarget = 1; | |
106 | fProjectile = "P"; | |
107 | fTarget = "P"; | |
108 | for (Int_t i=0; i<8; i++) fParentSelect[i]=fChildSelect[i]=0; | |
e36044d6 | 109 | } |
110 | ||
e36044d6 | 111 | AliGenMC::~AliGenMC() |
112 | { | |
113 | // Destructor | |
114 | } | |
115 | ||
116 | void AliGenMC::Init() | |
117 | { | |
118 | // | |
119 | // Initialization | |
120 | switch (fForceDecay) { | |
e345c619 | 121 | case kBSemiElectronic: |
e36044d6 | 122 | case kSemiElectronic: |
123 | case kDiElectron: | |
124 | case kBJpsiDiElectron: | |
125 | case kBPsiPrimeDiElectron: | |
e40b9538 | 126 | case kElectronEM: |
127 | case kDiElectronEM: | |
47fc6bd5 | 128 | fChildSelect[0] = kElectron; |
e36044d6 | 129 | break; |
2dcb5874 | 130 | case kHardMuons: |
e345c619 | 131 | case kBSemiMuonic: |
e36044d6 | 132 | case kSemiMuonic: |
133 | case kDiMuon: | |
38a19176 | 134 | case kJpsiDiMuon: |
e36044d6 | 135 | case kBJpsiDiMuon: |
136 | case kBPsiPrimeDiMuon: | |
137 | case kPiToMu: | |
138 | case kKaToMu: | |
cd159249 | 139 | case kWToMuon: |
140 | case kWToCharmToMuon: | |
2f299526 | 141 | case kZDiMuon: |
f5b581a1 | 142 | case kZDiElectron: |
e36044d6 | 143 | fChildSelect[0]=kMuonMinus; |
144 | break; | |
cd159249 | 145 | case kWToCharm: |
146 | break; | |
e36044d6 | 147 | case kHadronicD: |
af33df34 | 148 | case kHadronicDWithout4Bodies: |
e36044d6 | 149 | fChildSelect[0]=kPiPlus; |
150 | fChildSelect[1]=kKPlus; | |
151 | break; | |
00cb2f27 | 152 | case kPhiKK: |
027677ae | 153 | fChildSelect[0]=kKPlus; |
56d47239 | 154 | break; |
155 | case kBJpsi: | |
f2f8bbb9 | 156 | case kBJpsiUndecayed: |
00935af2 | 157 | fChildSelect[0]= 443; |
56d47239 | 158 | break; |
00935af2 | 159 | case kChiToJpsiGammaToMuonMuon: |
160 | fChildSelect[0]= 22; | |
161 | fChildSelect[1]= 13; | |
162 | break; | |
163 | case kChiToJpsiGammaToElectronElectron: | |
164 | fChildSelect[0]= 22; | |
165 | fChildSelect[1]= 11; | |
166 | break; | |
d3553100 | 167 | case kLambda: |
199786f7 | 168 | fChildSelect[0]= kProton; |
169 | fChildSelect[1]= 211; | |
170 | break; | |
9610308a | 171 | case kPsiPrimeJpsiDiElectron: |
e40b9538 | 172 | fChildSelect[0]= 211; |
173 | fChildSelect[1]= 11; | |
174 | break; | |
175 | case kGammaEM: | |
176 | fChildSelect[0] = kGamma; | |
177 | break; | |
199786f7 | 178 | case kOmega: |
e36044d6 | 179 | case kAll: |
2b1f8257 | 180 | case kAllMuonic: |
e36044d6 | 181 | case kNoDecay: |
d5f86442 | 182 | case kNoDecayHeavy: |
1fefb2d4 | 183 | case kNoDecayBeauty: |
847af604 | 184 | case kNeutralPion: |
482c0e0c | 185 | case kBeautyUpgrade: |
e36044d6 | 186 | break; |
187 | } | |
36d770d9 | 188 | |
189 | if (fZTarget != 0 && fAProjectile != 0) | |
190 | { | |
191 | fDyBoost = - 0.5 * TMath::Log(Double_t(fZProjectile) * Double_t(fATarget) / | |
192 | (Double_t(fZTarget) * Double_t(fAProjectile))); | |
193 | } | |
e36044d6 | 194 | } |
195 | ||
196 | ||
62d0ae06 | 197 | Bool_t AliGenMC::ParentSelected(Int_t ip) const |
e36044d6 | 198 | { |
199 | // True if particle is in list of parent particles to be selected | |
200 | for (Int_t i=0; i<8; i++) | |
201 | { | |
62d0ae06 | 202 | if (fParentSelect.At(i) == ip) return kTRUE; |
e36044d6 | 203 | } |
204 | return kFALSE; | |
205 | } | |
206 | ||
62d0ae06 | 207 | Bool_t AliGenMC::ChildSelected(Int_t ip) const |
e36044d6 | 208 | { |
209 | // True if particle is in list of decay products to be selected | |
210 | for (Int_t i=0; i<5; i++) | |
211 | { | |
62d0ae06 | 212 | if (fChildSelect.At(i) == ip) return kTRUE; |
e36044d6 | 213 | } |
214 | return kFALSE; | |
215 | } | |
216 | ||
4a33c50d | 217 | Bool_t AliGenMC::KinematicSelection(const TParticle *particle, Int_t flag) const |
e36044d6 | 218 | { |
219 | // Perform kinematic selection | |
43a333ec | 220 | Double_t pz = particle->Pz(); |
43a333ec | 221 | Double_t pt = particle->Pt(); |
222 | Double_t p = particle->P(); | |
223 | Double_t theta = particle->Theta(); | |
224 | Double_t mass = particle->GetCalcMass(); | |
225 | Double_t mt2 = pt * pt + mass * mass; | |
226 | Double_t phi = particle->Phi(); | |
d643e262 | 227 | Double_t e = particle->Energy(); |
228 | ||
229 | if (e == 0.) | |
230 | e = TMath::Sqrt(p * p + mass * mass); | |
231 | ||
95450c6d | 232 | |
95450c6d | 233 | Double_t y, y0; |
234 | ||
fef61e14 | 235 | if (TMath::Abs(pz) < e) { |
95450c6d | 236 | y = 0.5*TMath::Log((e+pz)/(e-pz)); |
237 | } else { | |
238 | y = 1.e10; | |
239 | } | |
e36044d6 | 240 | |
95450c6d | 241 | if (mt2) { |
242 | y0 = 0.5*TMath::Log((e+TMath::Abs(pz))*(e+TMath::Abs(pz))/mt2); | |
e36044d6 | 243 | } else { |
95450c6d | 244 | if (TMath::Abs(y) < 1.e10) { |
245 | y0 = y; | |
246 | } else { | |
247 | y0 = 1.e10; | |
248 | } | |
e36044d6 | 249 | } |
95450c6d | 250 | |
251 | y = (pz < 0) ? -y0 : y0; | |
e36044d6 | 252 | |
253 | if (flag == 0) { | |
254 | // | |
255 | // Primary particle cuts | |
256 | // | |
257 | // transverse momentum cut | |
258 | if (pt > fPtMax || pt < fPtMin) { | |
259 | // printf("\n failed pt cut %f %f %f \n",pt,fPtMin,fPtMax); | |
260 | return kFALSE; | |
261 | } | |
262 | // | |
263 | // momentum cut | |
264 | if (p > fPMax || p < fPMin) { | |
265 | // printf("\n failed p cut %f %f %f \n",p,fPMin,fPMax); | |
266 | return kFALSE; | |
267 | } | |
268 | // | |
269 | // theta cut | |
270 | if (theta > fThetaMax || theta < fThetaMin) { | |
271 | // printf("\n failed theta cut %f %f %f \n",theta,fThetaMin,fThetaMax); | |
272 | return kFALSE; | |
273 | } | |
274 | // | |
275 | // rapidity cut | |
276 | if (y > fYMax || y < fYMin) { | |
277 | // printf("\n failed y cut %f %f %f \n",y,fYMin,fYMax); | |
278 | return kFALSE; | |
279 | } | |
280 | // | |
281 | // phi cut | |
282 | if (phi > fPhiMax || phi < fPhiMin) { | |
283 | // printf("\n failed phi cut %f %f %f \n",phi,fPhiMin,fPhiMax); | |
284 | return kFALSE; | |
285 | } | |
286 | } else { | |
287 | // | |
288 | // Decay product cuts | |
289 | // | |
290 | // transverse momentum cut | |
291 | if (pt > fChildPtMax || pt < fChildPtMin) { | |
292 | // printf("\n failed pt cut %f %f %f \n",pt,fChildPtMin,fChildPtMax); | |
293 | return kFALSE; | |
294 | } | |
295 | // | |
296 | // momentum cut | |
297 | if (p > fChildPMax || p < fChildPMin) { | |
298 | // printf("\n failed p cut %f %f %f \n",p,fChildPMin,fChildPMax); | |
299 | return kFALSE; | |
300 | } | |
301 | // | |
302 | // theta cut | |
303 | if (theta > fChildThetaMax || theta < fChildThetaMin) { | |
304 | // printf("\n failed theta cut %f %f %f \n",theta,fChildThetaMin,fChildThetaMax); | |
305 | return kFALSE; | |
306 | } | |
307 | // | |
308 | // rapidity cut | |
309 | if (y > fChildYMax || y < fChildYMin) { | |
310 | // printf("\n failed y cut %f %f %f \n",y,fChildYMin,fChildYMax); | |
311 | return kFALSE; | |
312 | } | |
313 | // | |
314 | // phi cut | |
315 | if (phi > fChildPhiMax || phi < fChildPhiMin) { | |
316 | // printf("\n failed phi cut %f %f %f \n",phi,fChildPhiMin,fChildPhiMax); | |
317 | return kFALSE; | |
318 | } | |
319 | } | |
320 | ||
e36044d6 | 321 | return kTRUE; |
322 | } | |
323 | ||
65de9f86 | 324 | Bool_t AliGenMC::CheckAcceptanceGeometry(Int_t np, TClonesArray* particles) |
325 | { | |
e033748b | 326 | // Check the geometrical acceptance for particle. |
327 | ||
328 | Bool_t check ; | |
329 | Int_t numberOfPdgCodeParticleforAcceptanceCut = 0; | |
330 | Int_t numberOfAcceptedPdgCodeParticleforAcceptanceCut = 0; | |
65de9f86 | 331 | TParticle * particle; |
332 | Int_t i; | |
e033748b | 333 | for (i = 0; i < np; i++) { |
65de9f86 | 334 | particle = (TParticle *) particles->At(i); |
335 | if( TMath::Abs( particle->GetPdgCode() ) == TMath::Abs( fPdgCodeParticleforAcceptanceCut ) ) { | |
e033748b | 336 | numberOfPdgCodeParticleforAcceptanceCut++; |
337 | if (fGeometryAcceptance->Impact(particle)) numberOfAcceptedPdgCodeParticleforAcceptanceCut++; | |
65de9f86 | 338 | } |
339 | } | |
e033748b | 340 | if ( numberOfAcceptedPdgCodeParticleforAcceptanceCut > (fNumberOfAcceptedParticles-1) ) |
341 | check = kTRUE; | |
65de9f86 | 342 | else |
e033748b | 343 | check = kFALSE; |
65de9f86 | 344 | |
e033748b | 345 | return check; |
65de9f86 | 346 | } |
347 | ||
62d0ae06 | 348 | Int_t AliGenMC::CheckPDGCode(Int_t pdgcode) const |
e36044d6 | 349 | { |
350 | // | |
351 | // If the particle is in a diffractive state, then take action accordingly | |
352 | switch (pdgcode) { | |
353 | case 91: | |
354 | return 92; | |
355 | case 110: | |
356 | //rho_diff0 -- difficult to translate, return rho0 | |
357 | return 113; | |
358 | case 210: | |
359 | //pi_diffr+ -- change to pi+ | |
360 | return 211; | |
361 | case 220: | |
362 | //omega_di0 -- change to omega0 | |
363 | return 223; | |
364 | case 330: | |
365 | //phi_diff0 -- return phi0 | |
366 | return 333; | |
367 | case 440: | |
368 | //J/psi_di0 -- return J/psi | |
369 | return 443; | |
370 | case 2110: | |
371 | //n_diffr -- return neutron | |
372 | return 2112; | |
373 | case 2210: | |
374 | //p_diffr+ -- return proton | |
375 | return 2212; | |
376 | } | |
377 | //non diffractive state -- return code unchanged | |
378 | return pdgcode; | |
379 | } | |
3b945a60 | 380 | |
36d770d9 | 381 | void AliGenMC::Boost() |
3b945a60 | 382 | { |
383 | // | |
384 | // Boost cms into LHC lab frame | |
385 | // | |
386 | ||
36d770d9 | 387 | Double_t beta = TMath::TanH(fDyBoost); |
60e55aee | 388 | Double_t gamma = 1./TMath::Sqrt((1.-beta)*(1.+beta)); |
3b945a60 | 389 | Double_t gb = gamma * beta; |
390 | ||
e052713d | 391 | printf("\n Boosting particles to lab frame %f %f %f", fDyBoost, beta, gamma); |
3b945a60 | 392 | |
393 | Int_t i; | |
ea24f998 | 394 | Int_t np = fParticles.GetEntriesFast(); |
3b945a60 | 395 | for (i = 0; i < np; i++) |
396 | { | |
ea24f998 | 397 | TParticle* iparticle = (TParticle*) fParticles.At(i); |
3b945a60 | 398 | |
399 | Double_t e = iparticle->Energy(); | |
400 | Double_t px = iparticle->Px(); | |
401 | Double_t py = iparticle->Py(); | |
402 | Double_t pz = iparticle->Pz(); | |
403 | ||
404 | Double_t eb = gamma * e - gb * pz; | |
405 | Double_t pzb = -gb * e + gamma * pz; | |
406 | ||
407 | iparticle->SetMomentum(px, py, pzb, eb); | |
408 | } | |
409 | } | |
d97fb2bb | 410 | |
7eb751fe | 411 | void AliGenMC::BeamCrossAngle() |
412 | { | |
413 | // Applies a boost in the y-direction in order to take into account the | |
414 | // beam crossing angle | |
415 | ||
416 | Double_t thetaPr0, phiPr0, pyPr2, pzPr2; | |
417 | TVector3 beta; | |
418 | ||
419 | thetaPr0 = fXingAngleY / 2.; | |
420 | phiPr0 = 0; | |
421 | ||
422 | // Momentum of the CMS system | |
423 | pyPr2 = TMath::Sqrt(fEnergyCMS * fEnergyCMS/ 4 - 0.938 * 0.938) * TMath::Sin(thetaPr0); | |
424 | pzPr2 = TMath::Sqrt(fEnergyCMS * fEnergyCMS/ 4 - 0.938 * 0.938) * TMath::Cos(thetaPr0); | |
425 | ||
426 | TLorentzVector proj1Vect, proj2Vect, projVect; | |
427 | proj1Vect.SetPxPyPzE(0., pyPr2, pzPr2, fEnergyCMS/2); | |
428 | proj2Vect.SetPxPyPzE(0., pyPr2,-pzPr2, fEnergyCMS/2); | |
429 | projVect = proj1Vect + proj2Vect; | |
430 | beta=(1. / projVect.E()) * (projVect.Vect()); | |
431 | ||
432 | Int_t i; | |
433 | Int_t np = fParticles.GetEntriesFast(); | |
434 | for (i = 0; i < np; i++) | |
435 | { | |
436 | TParticle* iparticle = (TParticle*) fParticles.At(i); | |
437 | ||
438 | Double_t e = iparticle->Energy(); | |
439 | Double_t px = iparticle->Px(); | |
440 | Double_t py = iparticle->Py(); | |
441 | Double_t pz = iparticle->Pz(); | |
442 | ||
443 | TLorentzVector partIn; | |
444 | partIn.SetPxPyPzE(px,py,pz,e); | |
445 | partIn.Boost(beta); | |
446 | iparticle->SetMomentum(partIn.Px(),partIn.Py(),partIn.Pz(),partIn.E()); | |
447 | } | |
448 | } | |
449 | ||
450 | ||
d97fb2bb | 451 | void AliGenMC::AddHeader(AliGenEventHeader* header) |
452 | { | |
453 | // Passes header either to the container or to gAlice | |
454 | if (fContainer) { | |
e052713d | 455 | header->SetName(fName); |
d97fb2bb | 456 | fContainer->AddHeader(header); |
457 | } else { | |
458 | gAlice->SetGenEventHeader(header); | |
459 | } | |
460 | } |