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2c890605 | 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 | /* $Id$ */ | |
17 | ||
18 | // Class to generate correlated Heavy Flavor hadron pairs (one or several pairs | |
19 | // per event) using paramtrized kinematics of quark pairs from some generator | |
20 | // and quark fragmentation functions. | |
21 | // Is a generalisation of AliGenParam class for correlated pairs of hadrons. | |
22 | // In this version quark pairs and fragmentation functions are obtained from | |
b44c3901 | 23 | // Pythia6.124 using 100K events generated with kCharmppMNRwmi&kBeautyppMNRwmi |
2c890605 | 24 | // in pp collisions at 14 TeV. |
25 | // Decays are performed by Pythia. Used AliRoot version: v4-04-Release | |
26 | // Author: S. Grigoryan, LPC Clermont-Fd & YerPhI, Smbat.Grigoryan@cern.ch | |
b44c3901 | 27 | // July 07: added quarks in the stack (B. Vulpescu) |
2c890605 | 28 | //------------------------------------------------------------------------- |
29 | // How it works (for the given flavor): | |
30 | // | |
31 | // 1) Reads QQbar kinematical grid from the Input file and generates | |
32 | // quark pairs according to the weights of the cells. | |
33 | // It is a 5D grid in y1,y2,pt1,pt2 and deltaphi, with occupancy weights | |
34 | // of the cells obtained from Pythia (see details in GetQuarkPair). | |
35 | // 2) Reads "soft" and "hard" fragmentation functions (12 2D-histograms each, | |
36 | // for 12 pt bins) from the Input file, applies to quarks and produces hadrons | |
37 | // (only lower states, with proportions of species obtained from Pythia). | |
38 | // Fragmentation functions are the same for all hadron species and depend | |
39 | // on 2 variables - light cone energy-momentum fractions: | |
40 | // z1=(E_H + Pz_H)/(E_Q + Pz_Q), z2=(E_H - Pz_H)/(E_Q - Pz_Q). | |
41 | // "soft" & "hard" FFs correspond to "slower" & "faster" quark of a pair | |
42 | // (see details in GetHadronPair). | |
43 | // 3) Decays the hadrons and saves all the particles in the event stack in the | |
44 | // following order: HF hadron from Q, then its decay products, then HF hadron | |
45 | // from Qbar, then its decay productes, then next HF hadon pair (if any) | |
46 | // in the same way, etc... | |
47 | // 4) It is fast, e.g., generates the same number of events with a beauty pair | |
48 | // ~15 times faster than AliGenPythia with kBeautyppMNRwmi (w/o tracking) | |
49 | // | |
50 | // An Input file for each quark flavor is included in EVGEN/dataCorrHF/ | |
51 | // One can use also user-defined Input files. | |
52 | // | |
53 | // More details could be found in my presentation at DiMuonNet Workshop, Dec 2006: | |
54 | // http://www-dapnia.cea.fr/Sphn/Alice/DiMuonNet | |
55 | // and will be published in an Internal Note. | |
56 | // | |
57 | //------------------------------------------------------------------------- | |
58 | // How to use it: | |
59 | // | |
60 | // add the following typical lines in Config.C | |
61 | /* | |
62 | if (!strcmp(option,"corr")) { | |
63 | // Example for correlated charm or beauty hadron pair production | |
64 | ||
65 | // AliGenCorrHF *gener = new AliGenCorrHF(1, 4); // for charm, 1 pair per event | |
66 | AliGenCorrHF *gener = new AliGenCorrHF(1, 5); // for beauty, 1 pair per event | |
67 | ||
68 | gener->SetMomentumRange(0,9999); | |
69 | gener->SetCutOnChild(0); // 1/0 means cuts on children enable/disable | |
70 | gener->SetChildThetaRange(171.0,178.0); | |
71 | gener->SetOrigin(0,0,0); //vertex position | |
72 | gener->SetSigma(0,0,0); //Sigma in (X,Y,Z) (cm) on IP position | |
73 | gener->SetForceDecay(kSemiMuonic); | |
74 | gener->SetTrackingFlag(0); | |
75 | gener->Init(); | |
76 | } | |
77 | */ | |
78 | // and in aliroot do e.g. gAlice->Run(10,"Config.C") to produce 10 events. | |
79 | // One can include AliGenCorrHF in an AliGenCocktail generator. | |
80 | //-------------------------------------------------------------------------- | |
81 | ||
7ca4655f | 82 | #include <Riostream.h> |
83 | #include <TCanvas.h> | |
84 | #include <TClonesArray.h> | |
85 | #include <TDatabasePDG.h> | |
2c890605 | 86 | #include <TFile.h> |
2c890605 | 87 | #include <TH2F.h> |
2c890605 | 88 | #include <TLorentzVector.h> |
7ca4655f | 89 | #include <TMath.h> |
2c890605 | 90 | #include <TParticle.h> |
91 | #include <TParticlePDG.h> | |
7ca4655f | 92 | #include <TROOT.h> |
93 | #include <TRandom.h> | |
94 | #include <TTree.h> | |
2c890605 | 95 | #include <TVirtualMC.h> |
b44c3901 | 96 | #include <TVector3.h> |
2c890605 | 97 | |
98 | #include "AliGenCorrHF.h" | |
99 | #include "AliLog.h" | |
100 | #include "AliConst.h" | |
101 | #include "AliDecayer.h" | |
102 | #include "AliMC.h" | |
103 | #include "AliRun.h" | |
84555c93 | 104 | #include "AliGenEventHeader.h" |
2c890605 | 105 | |
106 | ClassImp(AliGenCorrHF) | |
107 | ||
108 | //Begin_Html | |
109 | /* | |
110 | <img src="picts/AliGenCorrHF.gif"> | |
111 | */ | |
112 | //End_Html | |
113 | ||
114 | Double_t AliGenCorrHF::fgdph[19] = {0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180}; | |
115 | Double_t AliGenCorrHF::fgy[31] = {-10,-7, -6.5, -6, -5.5, -5, -4.5, -4, -3.5, -3, -2.5, -2,- 1.5, -1, -0.5, 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 10}; | |
116 | Double_t AliGenCorrHF::fgpt[33] = {0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.6, 7.2, 7.8, 8.4, 9, 9.6, 10.3, 11.1, 12, 13.1, 14.3, 15.6, 17.1, 19, 21, 24, 28, 35, 50, 100}; | |
117 | Int_t AliGenCorrHF::fgnptbins = 12; | |
118 | Double_t AliGenCorrHF::fgptbmin[12] = {0, 0.5, 1, 1.5, 2, 2.5, 3, 4, 5, 6, 7, 9}; | |
119 | Double_t AliGenCorrHF::fgptbmax[12] = {0.5, 1, 1.5, 2, 2.5, 3, 4, 5, 6, 7, 9, 100}; | |
120 | ||
121 | Double_t* AliGenCorrHF::fgIntegral = 0; | |
122 | ||
123 | //____________________________________________________________ | |
124 | AliGenCorrHF::AliGenCorrHF(): | |
125 | fFileName(0), | |
126 | fFile(0), | |
127 | fQuark(0), | |
128 | fBias(0.), | |
129 | fTrials(0), | |
130 | fDecayer(0) | |
131 | { | |
132 | // Default constructor | |
133 | } | |
134 | ||
135 | //____________________________________________________________ | |
136 | AliGenCorrHF::AliGenCorrHF(Int_t npart, Int_t param): | |
137 | AliGenMC(npart), | |
138 | fFileName(0), | |
139 | fFile(0), | |
140 | fQuark(param), | |
141 | fBias(0.), | |
142 | fTrials(0), | |
143 | // fDecayer(new AliDecayerPythia()) | |
144 | fDecayer(0) | |
145 | { | |
146 | // Constructor using number of particles, quark type & default InputFile | |
147 | // | |
148 | if (fQuark != 5) fQuark = 4; | |
149 | fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/CharmppMNRwmiCorr100K.root"; | |
150 | if (fQuark == 5) fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/BeautyppMNRwmiCorr100K.root"; | |
151 | ||
152 | fName = "Default"; | |
153 | fTitle= "Generator for correlated pairs of HF hadrons"; | |
154 | ||
155 | fChildSelect.Set(5); | |
156 | for (Int_t i=0; i<5; i++) fChildSelect[i]=0; | |
157 | SetForceDecay(); | |
158 | SetCutOnChild(); | |
159 | SetChildMomentumRange(); | |
160 | SetChildPtRange(); | |
161 | SetChildPhiRange(); | |
162 | SetChildThetaRange(); | |
163 | } | |
164 | ||
165 | //___________________________________________________________________ | |
166 | AliGenCorrHF::AliGenCorrHF(char* tname, Int_t npart, Int_t param): | |
167 | AliGenMC(npart), | |
168 | fFileName(tname), | |
169 | fFile(0), | |
170 | fQuark(param), | |
171 | fBias(0.), | |
172 | fTrials(0), | |
173 | // fDecayer(new AliDecayerPythia()) | |
174 | fDecayer(0) | |
175 | { | |
176 | // Constructor using number of particles, quark type & user-defined InputFile | |
177 | // | |
178 | if (fQuark != 5) fQuark = 4; | |
179 | fName = "UserDefined"; | |
180 | fTitle= "Generator for correlated pairs of HF hadrons"; | |
181 | ||
182 | fChildSelect.Set(5); | |
183 | for (Int_t i=0; i<5; i++) fChildSelect[i]=0; | |
184 | SetForceDecay(); | |
185 | SetCutOnChild(); | |
186 | SetChildMomentumRange(); | |
187 | SetChildPtRange(); | |
188 | SetChildPhiRange(); | |
189 | SetChildThetaRange(); | |
190 | } | |
191 | ||
2c890605 | 192 | //____________________________________________________________ |
193 | AliGenCorrHF::~AliGenCorrHF() | |
194 | { | |
195 | // Destructor | |
196 | delete fFile; | |
197 | } | |
198 | ||
199 | //____________________________________________________________ | |
200 | void AliGenCorrHF::Init() | |
201 | { | |
202 | // Initialisation | |
203 | ||
204 | AliInfo(Form(" QQbar kinematics and fragm. functions from: %s",fFileName.Data() )); | |
205 | fFile = TFile::Open(fFileName.Data()); | |
206 | if(!fFile->IsOpen()){ | |
207 | AliError(Form("Could not open file %s",fFileName.Data() )); | |
208 | } | |
209 | ||
210 | ComputeIntegral(fFile); | |
b44c3901 | 211 | |
2c890605 | 212 | fParentWeight = 1./fNpart; // fNpart is number of HF-hadron pairs |
213 | ||
214 | // particle decay related initialization | |
215 | ||
216 | if (gMC) fDecayer = gMC->GetDecayer(); | |
217 | fDecayer->SetForceDecay(fForceDecay); | |
218 | fDecayer->Init(); | |
219 | ||
220 | // | |
221 | AliGenMC::Init(); | |
222 | } | |
2c890605 | 223 | //____________________________________________________________ |
224 | void AliGenCorrHF::Generate() | |
225 | { | |
226 | // | |
cb11fd27 | 227 | // Generate fNpart of correlated HF hadron pairs per event |
228 | // in the the desired theta and momentum windows (phi = 0 - 2pi). | |
84555c93 | 229 | // |
cb11fd27 | 230 | |
84555c93 | 231 | // Reinitialize decayer |
2c890605 | 232 | |
84555c93 | 233 | fDecayer->SetForceDecay(fForceDecay); |
234 | fDecayer->Init(); | |
235 | ||
236 | // | |
2c890605 | 237 | Float_t polar[3]= {0,0,0}; // Polarisation of the parent particle (for GEANT tracking) |
238 | Float_t origin0[3]; // Origin of the generated parent particle (for GEANT tracking) | |
239 | Float_t pt, pl, ptot; // Transverse, logitudinal and total momenta of the parent particle | |
240 | Float_t phi, theta; // Phi and theta spherical angles of the parent particle momentum | |
241 | Float_t p[3], pc[3], och[3];// Momentum, polarisation and origin of the children particles from lujet | |
84555c93 | 242 | Int_t nt, i, j, ipa, ihadron[2], iquark[2]; |
243 | Float_t wgtp, wgtch, random[6]; | |
244 | Float_t pq[2][3]; // Momenta of the two quarks | |
245 | Int_t ntq[2] = {-1, -1}; | |
cb11fd27 | 246 | Double_t tanhy2, qm = 0; |
2c890605 | 247 | |
b44c3901 | 248 | Double_t dphi=0, ptq[2], yq[2], pth[2], plh[2], ph[2], phih[2], phiq[2]; |
2c890605 | 249 | for (i=0; i<2; i++) { |
b44c3901 | 250 | ptq[i] =0; |
251 | yq[i] =0; | |
252 | pth[i] =0; | |
253 | plh[i] =0; | |
254 | phih[i] =0; | |
255 | phiq[i] =0; | |
2c890605 | 256 | ihadron[i] =0; |
84555c93 | 257 | iquark[i] =0; |
2c890605 | 258 | } |
259 | ||
cb11fd27 | 260 | // same quarks mass as in the fragmentation functions |
261 | if (fQuark == 4) qm = 1.20; | |
262 | else qm = 4.75; | |
263 | ||
2c890605 | 264 | static TClonesArray *particles; |
265 | // | |
266 | if(!particles) particles = new TClonesArray("TParticle",1000); | |
267 | ||
84555c93 | 268 | TDatabasePDG *pDataBase = TDatabasePDG::Instance(); |
269 | // | |
270 | ||
271 | // Calculating vertex position per event | |
2c890605 | 272 | for (j=0;j<3;j++) origin0[j]=fOrigin[j]; |
273 | if(fVertexSmear==kPerEvent) { | |
84555c93 | 274 | Vertex(); |
275 | for (j=0;j<3;j++) origin0[j]=fVertex[j]; | |
2c890605 | 276 | } |
277 | ||
84555c93 | 278 | ipa=0; |
279 | ||
280 | // Generating fNpart particles | |
281 | fNprimaries = 0; | |
282 | ||
283 | while (ipa<2*fNpart) { | |
284 | ||
285 | GetQuarkPair(fFile, fgIntegral, yq[0], yq[1], ptq[0], ptq[1], dphi); | |
286 | ||
287 | GetHadronPair(fFile, fQuark, yq[0], yq[1], ptq[0], ptq[1], ihadron[0], ihadron[1], plh[0], plh[1], pth[0], pth[1]); | |
288 | ||
289 | // Cuts from AliGenerator | |
290 | ||
291 | // Cut on theta | |
292 | theta=TMath::ATan2(pth[0],plh[0]); | |
293 | if(theta<fThetaMin || theta>fThetaMax) continue; | |
294 | theta=TMath::ATan2(pth[1],plh[1]); | |
295 | if(theta<fThetaMin || theta>fThetaMax) continue; | |
296 | ||
297 | // Cut on momentum | |
298 | ph[0]=TMath::Sqrt(pth[0]*pth[0]+plh[0]*plh[0]); | |
299 | if (ph[0]<fPMin || ph[0]>fPMax) continue; | |
300 | ph[1]=TMath::Sqrt(pth[1]*pth[1]+plh[1]*plh[1]); | |
301 | if (ph[1]<fPMin || ph[1]>fPMax) continue; | |
302 | ||
303 | // Add the quarks in the stack | |
304 | ||
305 | phiq[0] = Rndm()*k2PI; | |
306 | if (Rndm() < 0.5) { | |
b44c3901 | 307 | phiq[1] = phiq[0] + dphi*kDegrad; |
84555c93 | 308 | } else { |
309 | phiq[1] = phiq[0] - dphi*kDegrad; | |
310 | } | |
311 | if (phiq[1] > k2PI) phiq[1] -= k2PI; | |
312 | if (phiq[1] < 0 ) phiq[1] += k2PI; | |
313 | ||
314 | // quarks pdg | |
315 | iquark[0] = +fQuark; | |
316 | iquark[1] = -fQuark; | |
317 | ||
318 | // px and py | |
319 | TVector2 qvect1 = TVector2(); | |
320 | TVector2 qvect2 = TVector2(); | |
321 | qvect1.SetMagPhi(ptq[0],phiq[0]); | |
322 | qvect2.SetMagPhi(ptq[1],phiq[1]); | |
323 | pq[0][0] = qvect1.Px(); | |
324 | pq[0][1] = qvect1.Py(); | |
325 | pq[1][0] = qvect2.Px(); | |
326 | pq[1][1] = qvect2.Py(); | |
327 | ||
328 | // pz | |
cb11fd27 | 329 | tanhy2 = TMath::TanH(yq[0]); |
330 | tanhy2 *= tanhy2; | |
331 | pq[0][2] = TMath::Sqrt((ptq[0]*ptq[0]+qm*qm)*tanhy2/(1-tanhy2)); | |
332 | pq[0][2] = TMath::Sign((Double_t)pq[0][2],yq[0]); | |
333 | tanhy2 = TMath::TanH(yq[1]); | |
334 | tanhy2 *= tanhy2; | |
335 | pq[1][2] = TMath::Sqrt((ptq[1]*ptq[1]+qm*qm)*tanhy2/(1-tanhy2)); | |
336 | pq[1][2] = TMath::Sign((Double_t)pq[1][2],yq[1]); | |
84555c93 | 337 | |
338 | // Here we assume that |phi_H1 - phi_H2| = |phi_Q1 - phi_Q2| = dphi | |
339 | // which is a good approximation for heavy flavors in Pythia | |
340 | // ... moreover, same phi angles as for the quarks ... | |
341 | ||
342 | phih[0] = phiq[0]; | |
343 | phih[1] = phiq[1]; | |
b44c3901 | 344 | |
84555c93 | 345 | for (Int_t ihad = 0; ihad < 2; ihad++) { |
346 | while(1) { | |
347 | // | |
348 | // particle type | |
349 | Int_t iPart = ihadron[ihad]; | |
350 | fChildWeight=(fDecayer->GetPartialBranchingRatio(iPart))*fParentWeight; | |
351 | wgtp=fParentWeight; | |
352 | wgtch=fChildWeight; | |
353 | TParticlePDG *particle = pDataBase->GetParticle(iPart); | |
354 | Float_t am = particle->Mass(); | |
355 | phi = phih[ihad]; | |
356 | pt = pth[ihad]; | |
357 | pl = plh[ihad]; | |
358 | ptot=TMath::Sqrt(pt*pt+pl*pl); | |
359 | ||
360 | p[0]=pt*TMath::Cos(phi); | |
361 | p[1]=pt*TMath::Sin(phi); | |
362 | p[2]=pl; | |
b44c3901 | 363 | |
2c890605 | 364 | if(fVertexSmear==kPerTrack) { |
84555c93 | 365 | Rndm(random,6); |
366 | for (j=0;j<3;j++) { | |
367 | origin0[j]= | |
368 | fOrigin[j]+fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())* | |
369 | TMath::Sqrt(-2*TMath::Log(random[2*j+1])); | |
2c890605 | 370 | } |
371 | } | |
84555c93 | 372 | |
373 | // Looking at fForceDecay : | |
374 | // if fForceDecay != none Primary particle decays using | |
375 | // AliPythia and children are tracked by GEANT | |
376 | // | |
377 | // if fForceDecay == none Primary particle is tracked by GEANT | |
378 | // (In the latest, make sure that GEANT actually does all the decays you want) | |
379 | // | |
380 | ||
381 | if (fForceDecay != kNoDecay) { | |
382 | // Using lujet to decay particle | |
383 | Float_t energy=TMath::Sqrt(ptot*ptot+am*am); | |
384 | TLorentzVector pmom(p[0], p[1], p[2], energy); | |
385 | fDecayer->Decay(iPart,&pmom); | |
386 | // | |
387 | // select decay particles | |
388 | Int_t np=fDecayer->ImportParticles(particles); | |
389 | ||
390 | // Selecting GeometryAcceptance for particles fPdgCodeParticleforAcceptanceCut; | |
391 | if (fGeometryAcceptance) | |
392 | if (!CheckAcceptanceGeometry(np,particles)) continue; | |
393 | Int_t ncsel=0; | |
394 | Int_t* pFlag = new Int_t[np]; | |
395 | Int_t* pParent = new Int_t[np]; | |
396 | Int_t* pSelected = new Int_t[np]; | |
397 | Int_t* trackIt = new Int_t[np]; | |
398 | ||
399 | for (i=0; i<np; i++) { | |
400 | pFlag[i] = 0; | |
401 | pSelected[i] = 0; | |
402 | pParent[i] = -1; | |
403 | } | |
404 | ||
405 | if (np >1) { | |
406 | TParticle* iparticle = (TParticle *) particles->At(0); | |
407 | Int_t ipF, ipL; | |
408 | for (i = 1; i<np ; i++) { | |
409 | trackIt[i] = 1; | |
410 | iparticle = (TParticle *) particles->At(i); | |
411 | Int_t kf = iparticle->GetPdgCode(); | |
412 | Int_t ks = iparticle->GetStatusCode(); | |
413 | // flagged particle | |
414 | ||
415 | if (pFlag[i] == 1) { | |
416 | ipF = iparticle->GetFirstDaughter(); | |
417 | ipL = iparticle->GetLastDaughter(); | |
418 | if (ipF > 0) for (j=ipF-1; j<ipL; j++) pFlag[j]=1; | |
419 | continue; | |
420 | } | |
421 | ||
422 | // flag decay products of particles with long life-time (c tau > .3 mum) | |
423 | ||
424 | if (ks != 1) { | |
425 | //TParticlePDG *particle = pDataBase->GetParticle(kf); | |
426 | ||
427 | Double_t lifeTime = fDecayer->GetLifetime(kf); | |
428 | //Double_t mass = particle->Mass(); | |
429 | //Double_t width = particle->Width(); | |
430 | if (lifeTime > (Double_t) fMaxLifeTime) { | |
431 | ipF = iparticle->GetFirstDaughter(); | |
432 | ipL = iparticle->GetLastDaughter(); | |
433 | if (ipF > 0) for (j=ipF-1; j<ipL; j++) pFlag[j]=1; | |
434 | } else{ | |
435 | trackIt[i] = 0; | |
436 | pSelected[i] = 1; | |
2c890605 | 437 | } |
84555c93 | 438 | } // ks==1 ? |
439 | // | |
440 | // children | |
441 | ||
442 | if (ChildSelected(TMath::Abs(kf)) || fForceDecay == kAll && trackIt[i]) | |
443 | { | |
444 | if (fCutOnChild) { | |
445 | pc[0]=iparticle->Px(); | |
446 | pc[1]=iparticle->Py(); | |
447 | pc[2]=iparticle->Pz(); | |
448 | Bool_t childok = KinematicSelection(iparticle, 1); | |
449 | if(childok) { | |
450 | pSelected[i] = 1; | |
451 | ncsel++; | |
452 | } else { | |
453 | ncsel=-1; | |
454 | break; | |
455 | } // child kine cuts | |
456 | } else { | |
457 | pSelected[i] = 1; | |
458 | ncsel++; | |
459 | } // if child selection | |
460 | } // select muon | |
461 | } // decay particle loop | |
462 | } // if decay products | |
463 | ||
464 | Int_t iparent; | |
465 | if ((fCutOnChild && ncsel >0) || !fCutOnChild){ | |
466 | ipa++; | |
467 | // | |
468 | // Parent | |
469 | // quark | |
470 | PushTrack(0, -1, iquark[ihad], pq[ihad], origin0, polar, 0, kPPrimary, nt, wgtp); | |
471 | KeepTrack(nt); | |
472 | ntq[ihad] = nt; | |
84555c93 | 473 | // hadron |
474 | PushTrack(0, ntq[ihad], iPart, p, origin0, polar, 0, kPDecay, nt, wgtp); | |
475 | pParent[0] = nt; | |
476 | KeepTrack(nt); | |
477 | fNprimaries++; | |
84555c93 | 478 | |
479 | // | |
480 | // Decay Products | |
481 | // | |
482 | for (i = 1; i < np; i++) { | |
483 | if (pSelected[i]) { | |
484 | TParticle* iparticle = (TParticle *) particles->At(i); | |
485 | Int_t kf = iparticle->GetPdgCode(); | |
7f11c778 | 486 | Int_t jpa = iparticle->GetFirstMother()-1; |
2c890605 | 487 | |
84555c93 | 488 | och[0] = origin0[0]+iparticle->Vx()/10; |
489 | och[1] = origin0[1]+iparticle->Vy()/10; | |
490 | och[2] = origin0[2]+iparticle->Vz()/10; | |
491 | pc[0] = iparticle->Px(); | |
492 | pc[1] = iparticle->Py(); | |
493 | pc[2] = iparticle->Pz(); | |
2c890605 | 494 | |
7f11c778 | 495 | if (jpa > -1) { |
496 | iparent = pParent[jpa]; | |
84555c93 | 497 | } else { |
498 | iparent = -1; | |
499 | } | |
500 | ||
501 | PushTrack(fTrackIt*trackIt[i], iparent, kf, | |
502 | pc, och, polar, | |
503 | 0, kPDecay, nt, wgtch); | |
84555c93 | 504 | pParent[i] = nt; |
505 | KeepTrack(nt); | |
506 | fNprimaries++; | |
507 | } // Selected | |
508 | } // Particle loop | |
509 | } // Decays by Lujet | |
510 | particles->Clear(); | |
511 | if (pFlag) delete[] pFlag; | |
512 | if (pParent) delete[] pParent; | |
513 | if (pSelected) delete[] pSelected; | |
514 | if (trackIt) delete[] trackIt; | |
515 | } // kinematic selection | |
516 | else // nodecay option, so parent will be tracked by GEANT (pions, kaons, eta, omegas, baryons) | |
517 | { | |
518 | gAlice->GetMCApp()-> | |
519 | PushTrack(fTrackIt,-1,iPart,p,origin0,polar,0,kPPrimary,nt,wgtp); | |
520 | ipa++; | |
521 | fNprimaries++; | |
522 | } | |
2c890605 | 523 | break; |
524 | } // while(1) | |
84555c93 | 525 | } // hadron pair loop |
526 | } // event loop | |
527 | ||
2c890605 | 528 | SetHighWaterMark(nt); |
84555c93 | 529 | |
cb11fd27 | 530 | AliGenEventHeader* header = new AliGenEventHeader("CorrHF"); |
84555c93 | 531 | header->SetPrimaryVertex(fVertex); |
532 | header->SetNProduced(fNprimaries); | |
533 | AddHeader(header); | |
2c890605 | 534 | |
84555c93 | 535 | } |
2c890605 | 536 | //____________________________________________________________________________________ |
537 | Int_t AliGenCorrHF::IpCharm(TRandom* ran) | |
538 | { | |
539 | // Composition of lower state charm hadrons, containing a c-quark | |
540 | Float_t random; | |
541 | Int_t ip; // +- 411,421,431,4122,4132,4232,4332 | |
542 | random = ran->Rndm(); | |
543 | // Rates from Pythia6.214 using 100Kevents with kPyCharmppMNRwmi at 14 TeV. | |
544 | ||
545 | if (random < 0.6027) { | |
546 | ip=421; | |
547 | } else if (random < 0.7962) { | |
548 | ip=411; | |
549 | } else if (random < 0.9127) { | |
550 | ip=431; | |
551 | } else if (random < 0.9899) { | |
552 | ip=4122; | |
553 | } else if (random < 0.9948) { | |
554 | ip=4132; | |
555 | } else if (random < 0.9999) { | |
556 | ip=4232; | |
557 | } else { | |
558 | ip=4332; | |
559 | } | |
560 | ||
561 | return ip; | |
562 | } | |
563 | ||
564 | Int_t AliGenCorrHF::IpBeauty(TRandom* ran) | |
565 | { | |
566 | // Composition of lower state beauty hadrons, containing a b-quark | |
567 | Float_t random; | |
568 | Int_t ip; // +- 511,521,531,5122,5132,5232,5332 | |
569 | random = ran->Rndm(); | |
570 | // Rates from Pythia6.214 using 100Kevents with kPyBeautyppMNRwmi at 14 TeV. | |
571 | // B-Bbar mixing will be done by Pythia at the decay point | |
572 | if (random < 0.3965) { | |
573 | ip=-511; | |
574 | } else if (random < 0.7930) { | |
575 | ip=-521; | |
576 | } else if (random < 0.9112) { | |
577 | ip=-531; | |
578 | } else if (random < 0.9887) { | |
579 | ip=5122; | |
580 | } else if (random < 0.9943) { | |
581 | ip=5132; | |
582 | } else if (random < 0.9999) { | |
583 | ip=5232; | |
584 | } else { | |
585 | ip=5332; | |
586 | } | |
587 | ||
588 | return ip; | |
589 | } | |
590 | ||
591 | //____________________________________________________________________________________ | |
592 | Double_t AliGenCorrHF::ComputeIntegral(TFile* fG) // needed by GetQuarkPair | |
593 | { | |
594 | // Read QQbar kinematical 5D grid's cell occupancy weights | |
4c111067 | 595 | Int_t cell[6]; // cell[6]={wght,iy1,iy2,ipt1,ipt2,idph} |
2c890605 | 596 | TTree* tG = (TTree*) fG->Get("tGqq"); |
4c111067 | 597 | tG->GetBranch("cell")->SetAddress(&cell); |
2c890605 | 598 | Int_t nbins = tG->GetEntries(); |
599 | ||
600 | // delete previously computed integral (if any) | |
601 | if(fgIntegral) delete [] fgIntegral; | |
602 | ||
603 | fgIntegral = new Double_t[nbins+1]; | |
604 | fgIntegral[0] = 0; | |
605 | Int_t bin; | |
606 | for(bin=0;bin<nbins;bin++) { | |
607 | tG->GetEvent(bin); | |
608 | fgIntegral[bin+1] = fgIntegral[bin] + cell[0]; | |
609 | } | |
610 | // Normalize integral to 1 | |
611 | if (fgIntegral[nbins] == 0 ) { | |
612 | return 0; | |
613 | } | |
614 | for (bin=1;bin<=nbins;bin++) fgIntegral[bin] /= fgIntegral[nbins]; | |
615 | ||
616 | return fgIntegral[nbins]; | |
617 | } | |
618 | ||
619 | //____________________________________________________________________________________ | |
620 | void AliGenCorrHF::GetQuarkPair(TFile* fG, Double_t* fInt, Double_t &y1, Double_t &y2, Double_t &pt1, Double_t &pt2, Double_t &dphi) | |
621 | // modification of ROOT's TH3::GetRandom3 for 5D | |
622 | { | |
623 | // Read QQbar kinematical 5D grid's cell coordinates | |
4c111067 | 624 | Int_t cell[6]; // cell[6]={wght,iy1,iy2,ipt1,ipt2,idph} |
2c890605 | 625 | TTree* tG = (TTree*) fG->Get("tGqq"); |
4c111067 | 626 | tG->GetBranch("cell")->SetAddress(&cell); |
2c890605 | 627 | Int_t nbins = tG->GetEntries(); |
628 | Double_t rand[6]; | |
629 | gRandom->RndmArray(6,rand); | |
630 | Int_t ibin = TMath::BinarySearch(nbins,fInt,rand[0]); | |
631 | tG->GetEvent(ibin); | |
632 | y1 = fgy[cell[1]] + (fgy[cell[1]+1]-fgy[cell[1]])*rand[1]; | |
633 | y2 = fgy[cell[2]] + (fgy[cell[2]+1]-fgy[cell[2]])*rand[2]; | |
634 | pt1 = fgpt[cell[3]] + (fgpt[cell[3]+1]-fgpt[cell[3]])*rand[3]; | |
635 | pt2 = fgpt[cell[4]] + (fgpt[cell[4]+1]-fgpt[cell[4]])*rand[4]; | |
636 | dphi = fgdph[cell[5]]+ (fgdph[cell[5]+1]-fgdph[cell[5]])*rand[5]; | |
637 | } | |
638 | ||
639 | //____________________________________________________________________________________ | |
640 | void AliGenCorrHF::GetHadronPair(TFile* fG, Int_t idq, Double_t y1, Double_t y2, Double_t pt1, Double_t pt2, Int_t &id3, Int_t &id4, Double_t &pz3, Double_t &pz4, Double_t &pt3, Double_t &pt4) | |
641 | { | |
642 | // Generate a hadron pair | |
643 | Int_t (*fIpParaFunc )(TRandom*);//Pointer to particle type parametrisation function | |
644 | fIpParaFunc = IpCharm; | |
645 | Double_t mq = 1.2; // c & b quark masses (used in AliPythia) | |
646 | if (idq == 5) { | |
647 | fIpParaFunc = IpBeauty; | |
648 | mq = 4.75; | |
649 | } | |
650 | Double_t z11, z12, z21, z22, pz1, pz2, e1, e2, mh, ptemp, rand[2]; | |
651 | char tag[100]; | |
652 | TH2F *h2h[12], *h2s[12]; // hard & soft Fragmentation Functions | |
653 | for (Int_t ipt = 0; ipt<fgnptbins; ipt++) { | |
654 | sprintf(tag,"h2h_pt%d",ipt); | |
655 | h2h[ipt] = (TH2F*) fG->Get(tag); | |
656 | sprintf(tag,"h2s_pt%d",ipt); | |
657 | h2s[ipt] = (TH2F*) fG->Get(tag); | |
658 | } | |
659 | ||
660 | if (y1*y2 < 0) { | |
661 | for (Int_t ipt = 0; ipt<fgnptbins; ipt++) { | |
662 | if(pt1 >= fgptbmin[ipt] && pt1 < fgptbmax[ipt]) | |
663 | h2h[ipt]->GetRandom2(z11, z21); | |
664 | if(pt2 >= fgptbmin[ipt] && pt2 < fgptbmax[ipt]) | |
665 | h2h[ipt]->GetRandom2(z12, z22); | |
666 | } | |
667 | } | |
668 | else { | |
669 | if (TMath::Abs(y1) > TMath::Abs(y2)) { | |
670 | for (Int_t ipt = 0; ipt<fgnptbins; ipt++) { | |
671 | if(pt1 >= fgptbmin[ipt] && pt1 < fgptbmax[ipt]) | |
672 | h2h[ipt]->GetRandom2(z11, z21); | |
673 | if(pt2 >= fgptbmin[ipt] && pt2 < fgptbmax[ipt]) | |
674 | h2s[ipt]->GetRandom2(z12, z22); | |
675 | } | |
676 | } | |
677 | else { | |
678 | for (Int_t ipt = 0; ipt<fgnptbins; ipt++) { | |
679 | if(pt1 >= fgptbmin[ipt] && pt1 < fgptbmax[ipt]) | |
680 | h2s[ipt]->GetRandom2(z11, z21); | |
681 | if(pt2 >= fgptbmin[ipt] && pt2 < fgptbmax[ipt]) | |
682 | h2h[ipt]->GetRandom2(z12, z22); | |
683 | } | |
684 | } | |
685 | } | |
686 | gRandom->RndmArray(2,rand); | |
687 | ptemp = TMath::Sqrt(pt1*pt1 + mq*mq); | |
688 | pz1 = ptemp*TMath::SinH(y1); | |
689 | e1 = ptemp*TMath::CosH(y1); | |
690 | ptemp = TMath::Sqrt(pt2*pt2 + mq*mq); | |
691 | pz2 = ptemp*TMath::SinH(y2); | |
692 | e2 = ptemp*TMath::CosH(y2); | |
693 | ||
694 | id3 = fIpParaFunc(gRandom); | |
695 | mh = TDatabasePDG::Instance()->GetParticle(id3)->Mass(); | |
696 | ptemp = z11*z21*(e1*e1-pz1*pz1) - mh*mh; | |
697 | pt3 = (idq-3)*rand[0]; // some smearing at low pt, try better | |
698 | if (ptemp > 0) pt3 = TMath::Sqrt(ptemp); | |
699 | if (pz1 > 0) pz3 = (z11*(e1 + pz1) - z21*(e1 - pz1)) / 2; | |
700 | else pz3 = (z21*(e1 + pz1) - z11*(e1 - pz1)) / 2; | |
701 | e1 = TMath::Sqrt(pz3*pz3 + pt3*pt3 + mh*mh); | |
702 | ||
703 | id4 = - fIpParaFunc(gRandom); | |
704 | mh = TDatabasePDG::Instance()->GetParticle(id4)->Mass(); | |
705 | ptemp = z12*z22*(e2*e2-pz2*pz2) - mh*mh; | |
706 | pt4 = (idq-3)*rand[1]; // some smearing at low pt, try better | |
707 | if (ptemp > 0) pt4 = TMath::Sqrt(ptemp); | |
708 | if (pz2 > 0) pz4 = (z12*(e2 + pz2) - z22*(e2 - pz2)) / 2; | |
709 | else pz4 = (z22*(e2 + pz2) - z12*(e2 - pz2)) / 2; | |
710 | e2 = TMath::Sqrt(pz4*pz4 + pt4*pt4 + mh*mh); | |
711 | ||
712 | // small corr. instead of using Frag. Func. depending on yQ (in addition to ptQ) | |
713 | Float_t ycorr = 0.2, y3, y4; | |
714 | gRandom->RndmArray(2,rand); | |
715 | y3 = 0.5 * TMath::Log((e1 + pz3 + 1.e-13)/(e1 - pz3 + 1.e-13)); | |
716 | y4 = 0.5 * TMath::Log((e2 + pz4 + 1.e-13)/(e2 - pz4 + 1.e-13)); | |
717 | if(TMath::Abs(y3)<ycorr && TMath::Abs(y4)<ycorr && rand[0]>0.5) { | |
718 | ptemp = TMath::Sqrt(e1*e1 - pz3*pz3); | |
719 | y3 = 4*(1 - 2*rand[1]); | |
720 | pz3 = ptemp*TMath::SinH(y3); | |
721 | pz4 = pz3; | |
722 | } | |
723 | } |