]>
Commit | Line | Data |
---|---|---|
1 | ||
2 | //////////////////////////////////////////////////////////////////////////////// | |
3 | // | |
4 | // AliGenGeVSim is a class implementing GeVSim event generator. | |
5 | // | |
6 | // GeVSim is a simple Monte-Carlo event generator for testing detector and | |
7 | // algorythm performance especialy concerning flow and event-by-event studies | |
8 | // | |
9 | // In this event generator particles are generated from thermal distributions | |
10 | // without any dynamics and addicional constrains. Distribution parameters like | |
11 | // multiplicity, particle type yields, inverse slope parameters, flow coeficients | |
12 | // and expansion velocities are expleicite defined by the user. | |
13 | // | |
14 | // GeVSim contains four thermal distributions the same as | |
15 | // MevSim event generator developed for STAR experiment. | |
16 | // | |
17 | // In addition custom distributions can be used be the mean | |
18 | // either two dimensional formula (TF2), a two dimensional histogram or | |
19 | // two one dimensional histograms. | |
20 | // | |
21 | // Azimuthal distribution is deconvoluted from (Pt,Y) distribution | |
22 | // and is described by two Fourier coefficients representing | |
23 | // Directed and Elliptic flow. | |
24 | // | |
25 | //////////////////////////////////////////////////////////////////////////////// | |
26 | // | |
27 | // To apply flow to event ganerated by an arbitraly event generator | |
28 | // refer to AliGenAfterBurnerFlow class. | |
29 | // | |
30 | //////////////////////////////////////////////////////////////////////////////// | |
31 | // | |
32 | // For examples, parameters and testing macros refer to: | |
33 | // http:/home.cern.ch/radomski | |
34 | // | |
35 | // for more detailed description refer to ALICE NOTE | |
36 | // "GeVSim Monte-Carlo Event Generator" | |
37 | // S.Radosmki, P. Foka. | |
38 | // | |
39 | // Author: | |
40 | // Sylwester Radomski, | |
41 | // GSI, March 2002 | |
42 | // | |
43 | // S.Radomski@gsi.de | |
44 | // | |
45 | //////////////////////////////////////////////////////////////////////////////// | |
46 | // | |
47 | // Updated and revised: September 2002, S. Radomski, GSI | |
48 | // | |
49 | //////////////////////////////////////////////////////////////////////////////// | |
50 | ||
51 | ||
52 | #include <Riostream.h> | |
53 | #include <TCanvas.h> | |
54 | #include <TF1.h> | |
55 | #include <TF2.h> | |
56 | #include <TH1.h> | |
57 | #include <TH2.h> | |
58 | #include <TObjArray.h> | |
59 | #include <TPDGCode.h> | |
60 | #include <TParticle.h> | |
61 | #include <TROOT.h> | |
62 | ||
63 | ||
64 | #include "AliGeVSimParticle.h" | |
65 | #include "AliGenGeVSim.h" | |
66 | #include "AliGenGeVSimEventHeader.h" | |
67 | #include "AliGenerator.h" | |
68 | #include "AliRun.h" | |
69 | ||
70 | ||
71 | ClassImp(AliGenGeVSim); | |
72 | ||
73 | ////////////////////////////////////////////////////////////////////////////////// | |
74 | ||
75 | AliGenGeVSim::AliGenGeVSim() : AliGenerator(-1) { | |
76 | // | |
77 | // Default constructor | |
78 | // | |
79 | ||
80 | fPsi = 0; | |
81 | fIsMultTotal = kTRUE; | |
82 | ||
83 | //PH InitFormula(); | |
84 | for (Int_t i=0; i<4; i++) | |
85 | fPtYFormula[i] = 0; | |
86 | } | |
87 | ||
88 | ////////////////////////////////////////////////////////////////////////////////// | |
89 | ||
90 | AliGenGeVSim::AliGenGeVSim(Float_t psi, Bool_t isMultTotal) : AliGenerator(-1) { | |
91 | // | |
92 | // Standard Constructor. | |
93 | // | |
94 | // models - thermal model to be used: | |
95 | // 1 - deconvoluted pt and Y source | |
96 | // 2,3 - thermalized sphericaly symetric sources | |
97 | // 4 - thermalized source with expansion | |
98 | // 5 - custom model defined in TF2 object named "gevsimPtY" | |
99 | // 6 - custom model defined by two 1D histograms | |
100 | // 7 - custom model defined by 2D histogram | |
101 | // | |
102 | // psi - reaction plane in degrees | |
103 | // isMultTotal - multiplicity mode | |
104 | // kTRUE - total multiplicity (default) | |
105 | // kFALSE - dN/dY at midrapidity | |
106 | // | |
107 | ||
108 | // checking consistancy | |
109 | ||
110 | if (psi < 0 || psi > 360 ) | |
111 | Error ("AliGenGeVSim", "Reaction plane angle ( %d )out of range [0..360]", psi); | |
112 | ||
113 | fPsi = psi * TMath::Pi() / 180. ; | |
114 | fIsMultTotal = isMultTotal; | |
115 | ||
116 | // initialization | |
117 | ||
118 | fPartTypes = new TObjArray(); | |
119 | InitFormula(); | |
120 | } | |
121 | ||
122 | ////////////////////////////////////////////////////////////////////////////////// | |
123 | ||
124 | AliGenGeVSim::~AliGenGeVSim() { | |
125 | // | |
126 | // Default Destructor | |
127 | // | |
128 | // Removes TObjArray keeping list of registered particle types | |
129 | // | |
130 | ||
131 | if (fPartTypes != NULL) delete fPartTypes; | |
132 | } | |
133 | ||
134 | ||
135 | ////////////////////////////////////////////////////////////////////////////////// | |
136 | ||
137 | Bool_t AliGenGeVSim::CheckPtYPhi(Float_t pt, Float_t y, Float_t phi) { | |
138 | // | |
139 | // private function used by Generate() | |
140 | // | |
141 | // Check bounds of Pt, Rapidity and Azimuthal Angle of a track | |
142 | // Used only when generating particles from a histogram | |
143 | // | |
144 | ||
145 | if ( TestBit(kPtRange) && ( pt < fPtMin || pt > fPtMax )) return kFALSE; | |
146 | if ( TestBit(kPhiRange) && ( phi < fPhiMin || phi > fPhiMax )) return kFALSE; | |
147 | if ( TestBit(kYRange) && ( y < fYMin || y > fYMax )) return kFALSE; | |
148 | ||
149 | return kTRUE; | |
150 | } | |
151 | ||
152 | ////////////////////////////////////////////////////////////////////////////////// | |
153 | ||
154 | Bool_t AliGenGeVSim::CheckAcceptance(Float_t p[3]) { | |
155 | // | |
156 | // private function used by Generate() | |
157 | // | |
158 | // Check bounds of a total momentum and theta of a track | |
159 | // | |
160 | ||
161 | if ( TestBit(kThetaRange) ) { | |
162 | ||
163 | Double_t theta = TMath::ATan2( TMath::Sqrt(p[0]*p[0]+p[1]*p[1]), p[2]); | |
164 | if ( theta < fThetaMin || theta > fThetaMax ) return kFALSE; | |
165 | } | |
166 | ||
167 | ||
168 | if ( TestBit(kMomentumRange) ) { | |
169 | ||
170 | Double_t momentum = TMath::Sqrt(p[0]*p[0] + p[1]*p[1] + p[2]*p[2]); | |
171 | if ( momentum < fPMin || momentum > fPMax) return kFALSE; | |
172 | } | |
173 | ||
174 | return kTRUE; | |
175 | } | |
176 | ||
177 | ////////////////////////////////////////////////////////////////////////////////// | |
178 | ||
179 | void AliGenGeVSim::InitFormula() { | |
180 | // | |
181 | // private function | |
182 | // | |
183 | // Initalizes formulas used in GeVSim. | |
184 | // Manages strings and creates TFormula objects from strings | |
185 | // | |
186 | ||
187 | // Deconvoluted Pt Y formula | |
188 | ||
189 | // ptForm: pt -> x , mass -> [0] , temperature -> [1] | |
190 | // y Form: y -> x , sigmaY -> [0] | |
191 | ||
192 | const char* ptForm = " x * exp( -sqrt([0]*[0] + x*x) / [1] )"; | |
193 | const char* yForm = " exp ( - x*x / (2 * [0]*[0] ) )"; | |
194 | ||
195 | fPtFormula = new TF1("gevsimPt", ptForm, 0, 3); | |
196 | fYFormula = new TF1("gevsimRapidity", yForm, -3, 3); | |
197 | ||
198 | fPtFormula->SetParNames("mass", "temperature"); | |
199 | fPtFormula->SetParameters(1., 1.); | |
200 | ||
201 | fYFormula->SetParName(0, "sigmaY"); | |
202 | fYFormula->SetParameter(0, 1.); | |
203 | ||
204 | // Grid for Pt and Y | |
205 | fPtFormula->SetNpx(100); | |
206 | fYFormula->SetNpx(100); | |
207 | ||
208 | ||
209 | // Models 1-3 | |
210 | ||
211 | // pt -> x , Y -> y | |
212 | // mass -> [0] , temperature -> [1] , expansion velocity -> [2] | |
213 | ||
214 | ||
215 | const char *formE = " ( sqrt([0]*[0] + x*x) * cosh(y) ) "; | |
216 | const char *formG = " ( 1 / sqrt( 1 - [2]*[2] ) ) "; | |
217 | const char *formYp = "( [2]*sqrt(([0]*[0]+x*x)*cosh(y)*cosh(y)-[0]*[0])/([1]*sqrt(1-[2]*[2]))) "; | |
218 | ||
219 | const char* formula[3] = { | |
220 | " x * %s * exp( -%s / [1]) ", | |
221 | " (x * %s) / ( exp( %s / [1]) - 1 ) ", | |
222 | " x*%s*exp(-%s*%s/[1])*((sinh(%s)/%s)+([1]/(%s*%s))*(sinh(%s)/%s-cosh(%s)))" | |
223 | }; | |
224 | ||
225 | const char* paramNames[3] = {"mass", "temperature", "expVel"}; | |
226 | ||
227 | char buffer[1024]; | |
228 | ||
229 | sprintf(buffer, formula[0], formE, formE); | |
230 | fPtYFormula[0] = new TF2("gevsimPtY_2", buffer, 0, 3, -2, 2); | |
231 | ||
232 | sprintf(buffer, formula[1], formE, formE); | |
233 | fPtYFormula[1] = new TF2("gevsimPtY_3", buffer, 0, 3, -2, 2); | |
234 | ||
235 | sprintf(buffer, formula[2], formE, formG, formE, formYp, formYp, formG, formE, formYp, formYp, formYp); | |
236 | fPtYFormula[2] = new TF2("gevsimPtY_4", buffer, 0, 3, -2, 2); | |
237 | ||
238 | fPtYFormula[3] = 0; | |
239 | ||
240 | ||
241 | // setting names & initialisation | |
242 | ||
243 | Int_t i, j; | |
244 | for (i=0; i<3; i++) { | |
245 | ||
246 | fPtYFormula[i]->SetNpx(100); // step 30 MeV | |
247 | fPtYFormula[i]->SetNpy(100); // | |
248 | ||
249 | for (j=0; j<3; j++) { | |
250 | ||
251 | if ( i != 2 && j == 2 ) continue; // ExpVel | |
252 | fPtYFormula[i]->SetParName(j, paramNames[j]); | |
253 | fPtYFormula[i]->SetParameter(j, 0.5); | |
254 | } | |
255 | } | |
256 | ||
257 | // Phi Flow Formula | |
258 | ||
259 | // phi -> x | |
260 | // Psi -> [0] , Direct Flow -> [1] , Ellipticla Flow -> [2] | |
261 | ||
262 | const char* phiForm = " 1 + 2*[1]*cos(x-[0]) + 2*[2]*cos(2*(x-[0])) "; | |
263 | fPhiFormula = new TF1("gevsimPhi", phiForm, 0, 2*TMath::Pi()); | |
264 | ||
265 | fPhiFormula->SetParNames("psi", "directed", "elliptic"); | |
266 | fPhiFormula->SetParameters(0., 0., 0.); | |
267 | ||
268 | fPhiFormula->SetNpx(180); | |
269 | ||
270 | } | |
271 | ||
272 | ////////////////////////////////////////////////////////////////////////////////// | |
273 | ||
274 | void AliGenGeVSim::AddParticleType(AliGeVSimParticle *part) { | |
275 | // | |
276 | // Adds new type of particles. | |
277 | // | |
278 | // Parameters are defeined in AliGeVSimParticle object | |
279 | // This method has to be called for every particle type | |
280 | // | |
281 | ||
282 | if (fPartTypes == NULL) | |
283 | fPartTypes = new TObjArray(); | |
284 | ||
285 | fPartTypes->Add(part); | |
286 | } | |
287 | ||
288 | ////////////////////////////////////////////////////////////////////////////////// | |
289 | ||
290 | void AliGenGeVSim::SetMultTotal(Bool_t isTotal) { | |
291 | // | |
292 | // | |
293 | // | |
294 | ||
295 | fIsMultTotal = isTotal; | |
296 | } | |
297 | ||
298 | ////////////////////////////////////////////////////////////////////////////////// | |
299 | ||
300 | Float_t AliGenGeVSim::FindScaler(Int_t paramId, Int_t pdg) { | |
301 | // | |
302 | // private function | |
303 | // Finds Scallar for a given parameter. | |
304 | // Function used in event-by-event mode. | |
305 | // | |
306 | // There are two types of scallars: deterministic and random | |
307 | // and they can work on either global or particle type level. | |
308 | // For every variable there are four scallars defined. | |
309 | // | |
310 | // Scallars are named as folowa | |
311 | // deterministic global level : "gevsimParam" (eg. "gevsimTemp") | |
312 | // deterinistig type level : "gevsimPdgParam" (eg. "gevsim211Mult") | |
313 | // random global level : "gevsimParamRndm" (eg. "gevsimMultRndm") | |
314 | // random type level : "gevsimPdgParamRndm" (eg. "gevsim-211V2Rndm"); | |
315 | // | |
316 | // Pdg - code of a particle type in PDG standard (see: http://pdg.lbl.gov) | |
317 | // Param - parameter name. Allowed parameters: | |
318 | // | |
319 | // "Temp" - inverse slope parameter | |
320 | // "SigmaY" - rapidity width - for model (1) only | |
321 | // "ExpVel" - expansion velocity - for model (4) only | |
322 | // "V1" - directed flow | |
323 | // "V2" - elliptic flow | |
324 | // "Mult" - multiplicity | |
325 | // | |
326 | ||
327 | ||
328 | static const char* params[] = {"Temp", "SigmaY", "ExpVel", "V1", "V2", "Mult"}; | |
329 | static const char* ending[] = {"", "Rndm"}; | |
330 | ||
331 | static const char* patt1 = "gevsim%s%s"; | |
332 | static const char* patt2 = "gevsim%d%s%s"; | |
333 | ||
334 | char buffer[80]; | |
335 | TF1 *form; | |
336 | ||
337 | Float_t scaler = 1.; | |
338 | ||
339 | // Scaler evoluation: i - global/local, j - determ/random | |
340 | ||
341 | Int_t i, j; | |
342 | ||
343 | for (i=0; i<2; i++) { | |
344 | for (j=0; j<2; j++) { | |
345 | ||
346 | form = 0; | |
347 | ||
348 | if (i == 0) sprintf(buffer, patt1, params[paramId], ending[j]); | |
349 | else sprintf(buffer, patt2, pdg, params[paramId], ending[j]); | |
350 | ||
351 | form = (TF1 *)gROOT->GetFunction(buffer); | |
352 | ||
353 | if (form != 0) { | |
354 | if (j == 0) scaler *= form->Eval(gAlice->GetEvNumber()); | |
355 | if (j == 1) { | |
356 | form->SetParameter(0, gAlice->GetEvNumber()); | |
357 | scaler *= form->GetRandom(); | |
358 | } | |
359 | } | |
360 | } | |
361 | } | |
362 | ||
363 | return scaler; | |
364 | } | |
365 | ||
366 | ////////////////////////////////////////////////////////////////////////////////// | |
367 | ||
368 | void AliGenGeVSim::DetermineReactionPlane() { | |
369 | // | |
370 | // private function used by Generate() | |
371 | // | |
372 | // Retermines Reaction Plane angle and set this value | |
373 | // as a parameter [0] in fPhiFormula | |
374 | // | |
375 | // Note: if "gevsimPsiRndm" function is found it override both | |
376 | // "gevsimPhi" function and initial fPsi value | |
377 | // | |
378 | ||
379 | TF1 *form; | |
380 | ||
381 | form = 0; | |
382 | form = (TF1 *)gROOT->GetFunction("gevsimPsi"); | |
383 | if (form) fPsi = form->Eval(gAlice->GetEvNumber()) * TMath::Pi() / 180; | |
384 | ||
385 | form = 0; | |
386 | form = (TF1 *)gROOT->GetFunction("gevsimPsiRndm"); | |
387 | if (form) fPsi = form->GetRandom() * TMath::Pi() / 180; | |
388 | ||
389 | ||
390 | cout << "Psi = " << fPsi << "\t" << (Int_t)(fPsi*180./TMath::Pi()) << endl; | |
391 | ||
392 | fPhiFormula->SetParameter(0, fPsi); | |
393 | } | |
394 | ||
395 | ////////////////////////////////////////////////////////////////////////////////// | |
396 | ||
397 | Float_t AliGenGeVSim::GetdNdYToTotal() { | |
398 | // | |
399 | // Private, helper function used by Generate() | |
400 | // | |
401 | // Returns total multiplicity to dN/dY ration using current distribution. | |
402 | // The function have to be called after setting distribution and its | |
403 | // parameters (like temperature). | |
404 | // | |
405 | ||
406 | Float_t integ, mag; | |
407 | const Double_t maxPt = 3.0, maxY = 2.; | |
408 | ||
409 | if (fModel == 1) { | |
410 | ||
411 | integ = fYFormula->Integral(-maxY, maxY); | |
412 | mag = fYFormula->Eval(0); | |
413 | return integ/mag; | |
414 | } | |
415 | ||
416 | // 2D formula standard or custom | |
417 | ||
418 | if (fModel > 1 && fModel < 6) { | |
419 | ||
420 | integ = ((TF2*)fCurrentForm)->Integral(0,maxPt, -maxY, maxY); | |
421 | mag = ((TF2*)fCurrentForm)->Integral(0, maxPt, -0.1, 0.1) / 0.2; | |
422 | return integ/mag; | |
423 | } | |
424 | ||
425 | // 2 1D histograms | |
426 | ||
427 | if (fModel == 6) { | |
428 | ||
429 | integ = fHist[1]->Integral(); | |
430 | mag = fHist[0]->GetBinContent(fHist[0]->FindBin(0.)); | |
431 | mag /= fHist[0]->GetBinWidth(fHist[0]->FindBin(0.)); | |
432 | return integ/mag; | |
433 | } | |
434 | ||
435 | // 2D histogram | |
436 | ||
437 | if (fModel == 7) { | |
438 | ||
439 | // Not tested ... | |
440 | Int_t yBins = fPtYHist->GetNbinsY(); | |
441 | Int_t ptBins = fPtYHist->GetNbinsX(); | |
442 | ||
443 | integ = fPtYHist->Integral(0, ptBins, 0, yBins); | |
444 | mag = fPtYHist->Integral(0, ptBins, (yBins/2)-1, (yBins/2)+1 ) / 2; | |
445 | return integ/mag; | |
446 | } | |
447 | ||
448 | return 1; | |
449 | } | |
450 | ||
451 | ////////////////////////////////////////////////////////////////////////////////// | |
452 | ||
453 | void AliGenGeVSim::SetFormula(Int_t pdg) { | |
454 | // | |
455 | // Private function used by Generate() | |
456 | // | |
457 | // Configure a formula for a given particle type and model Id (in fModel). | |
458 | // If custom formula or histogram was selected the function tries | |
459 | // to find it. | |
460 | // | |
461 | // The function implements naming conventions for custom distributions names | |
462 | // | |
463 | ||
464 | char buff[40]; | |
465 | const char* msg[4] = { | |
466 | "Custom Formula for Pt Y distribution not found [pdg = %d]", | |
467 | "Histogram for Pt distribution not found [pdg = %d]", | |
468 | "Histogram for Y distribution not found [pdg = %d]", | |
469 | "HIstogram for Pt Y dostribution not found [pdg = %d]" | |
470 | }; | |
471 | ||
472 | const char* pattern[8] = { | |
473 | "gevsimDistPtY", "gevsimDist%dPtY", | |
474 | "gevsimHistPt", "gevsimHist%dPt", | |
475 | "gevsimHistY", "gevsimHist%dY", | |
476 | "gevsimHistPtY", "gevsimHist%dPtY" | |
477 | }; | |
478 | ||
479 | const char *where = "SetFormula"; | |
480 | ||
481 | ||
482 | if (fModel < 1 || fModel > 7) | |
483 | Error("SetFormula", "Model Id (%d) out of range [1-7]", fModel); | |
484 | ||
485 | ||
486 | // standard models | |
487 | ||
488 | if (fModel == 1) fCurrentForm = fPtFormula; | |
489 | if (fModel > 1 && fModel < 5) fCurrentForm = fPtYFormula[fModel-2]; | |
490 | ||
491 | ||
492 | // custom model defined by a formula | |
493 | ||
494 | if (fModel == 5) { | |
495 | ||
496 | fCurrentForm = 0; | |
497 | fCurrentForm = (TF2*)gROOT->GetFunction(pattern[0]); | |
498 | ||
499 | if (!fCurrentForm) { | |
500 | ||
501 | sprintf(buff, pattern[1], pdg); | |
502 | fCurrentForm = (TF2*)gROOT->GetFunction(buff); | |
503 | ||
504 | if (!fCurrentForm) Error(where, msg[0], pdg); | |
505 | } | |
506 | } | |
507 | ||
508 | // 2 1D histograms | |
509 | ||
510 | if (fModel == 6) { | |
511 | ||
512 | for (Int_t i=0; i<2; i++) { | |
513 | ||
514 | fHist[i] = 0; | |
515 | fHist[i] = (TH1D*)gROOT->FindObject(pattern[2+2*i]); | |
516 | ||
517 | if (!fHist[i]) { | |
518 | ||
519 | sprintf(buff, pattern[3+2*i], pdg); | |
520 | fHist[i] = (TH1D*)gROOT->FindObject(buff); | |
521 | ||
522 | if (!fHist[i]) Error(where, msg[1+i], pdg); | |
523 | } | |
524 | } | |
525 | } | |
526 | ||
527 | // 2d histogram | |
528 | ||
529 | if (fModel == 7) { | |
530 | ||
531 | fPtYHist = 0; | |
532 | fPtYHist = (TH2D*)gROOT->FindObject(pattern[6]); | |
533 | ||
534 | if (!fPtYHist) { | |
535 | ||
536 | sprintf(buff, pattern[7], pdg); | |
537 | fPtYHist = (TH2D*)gROOT->FindObject(buff); | |
538 | } | |
539 | ||
540 | if (!fPtYHist) Error(where, msg[4], pdg); | |
541 | } | |
542 | ||
543 | } | |
544 | ||
545 | ////////////////////////////////////////////////////////////////////////////////// | |
546 | ||
547 | void AliGenGeVSim:: AdjustFormula() { | |
548 | // | |
549 | // Private Function | |
550 | // Adjust fomula bounds according to acceptance cuts. | |
551 | // | |
552 | // Since GeVSim is producing "thermal" particles Pt | |
553 | // is cut at 3 GeV even when acceptance extends to grater momenta. | |
554 | // | |
555 | // WARNING ! | |
556 | // If custom formula was provided function preserves | |
557 | // original cuts. | |
558 | // | |
559 | ||
560 | const Double_t kMaxPt = 3.0; | |
561 | const Double_t kMaxY = 2.0; | |
562 | Double_t minPt, maxPt, minY, maxY; | |
563 | ||
564 | ||
565 | if (fModel > 4) return; | |
566 | ||
567 | // max Pt | |
568 | if (TestBit(kPtRange) && fPtMax < kMaxPt ) maxPt = fPtMax; | |
569 | else maxPt = kMaxPt; | |
570 | ||
571 | // min Pt | |
572 | if (TestBit(kPtRange)) minPt = fPtMin; | |
573 | else minPt = 0; | |
574 | ||
575 | if (TestBit(kPtRange) && fPtMin > kMaxPt ) | |
576 | Warning("Acceptance", "Minimum Pt (%3.2f GeV) greater that 3.0 GeV ", fPtMin); | |
577 | ||
578 | // Max Pt < Max P | |
579 | if (TestBit(kMomentumRange) && fPtMax < maxPt) maxPt = fPtMax; | |
580 | ||
581 | // max and min rapidity | |
582 | if (TestBit(kYRange)) { | |
583 | minY = fYMin; | |
584 | maxY = fYMax; | |
585 | } else { | |
586 | minY = -kMaxY; | |
587 | maxY = kMaxY; | |
588 | } | |
589 | ||
590 | // adjust formula | |
591 | ||
592 | if (fModel == 1) { | |
593 | fPtFormula->SetRange(fPtMin, maxPt); | |
594 | fYFormula->SetRange(fYMin, fYMax); | |
595 | } | |
596 | ||
597 | if (fModel > 1) | |
598 | ((TF2*)fCurrentForm)->SetRange(minPt, minY, maxPt, maxY); | |
599 | ||
600 | // azimuthal cut | |
601 | ||
602 | if (TestBit(kPhiRange)) | |
603 | fPhiFormula->SetRange(fPhiMin, fPhiMax); | |
604 | ||
605 | } | |
606 | ||
607 | ////////////////////////////////////////////////////////////////////////////////// | |
608 | ||
609 | void AliGenGeVSim::GetRandomPtY(Double_t &pt, Double_t &y) { | |
610 | // | |
611 | // Private function used by Generate() | |
612 | // | |
613 | // Returns random values of Pt and Y corresponding to selected | |
614 | // distribution. | |
615 | // | |
616 | ||
617 | if (fModel == 1) { | |
618 | pt = fPtFormula->GetRandom(); | |
619 | y = fYFormula->GetRandom(); | |
620 | return; | |
621 | } | |
622 | ||
623 | if (fModel > 1 && fModel < 6) { | |
624 | ((TF2*)fCurrentForm)->GetRandom2(pt, y); | |
625 | return; | |
626 | } | |
627 | ||
628 | if (fModel == 6) { | |
629 | pt = fHist[0]->GetRandom(); | |
630 | y = fHist[1]->GetRandom(); | |
631 | } | |
632 | ||
633 | if (fModel == 7) { | |
634 | fPtYHist->GetRandom2(pt, y); | |
635 | return; | |
636 | } | |
637 | } | |
638 | ||
639 | ////////////////////////////////////////////////////////////////////////////////// | |
640 | ||
641 | void AliGenGeVSim::Init() { | |
642 | // | |
643 | // Standard AliGenerator initializer. | |
644 | // does nothing | |
645 | // | |
646 | } | |
647 | ||
648 | ////////////////////////////////////////////////////////////////////////////////// | |
649 | ||
650 | void AliGenGeVSim::Generate() { | |
651 | // | |
652 | // Standard AliGenerator function | |
653 | // This function do actual job and puts particles on stack. | |
654 | // | |
655 | ||
656 | PDG_t pdg; // particle type | |
657 | Float_t mass; // particle mass | |
658 | Float_t orgin[3] = {0,0,0}; // particle orgin [cm] | |
659 | Float_t polar[3] = {0,0,0}; // polarisation | |
660 | Float_t time = 0; // time of creation | |
661 | ||
662 | Float_t multiplicity = 0; | |
663 | Bool_t isMultTotal = kTRUE; | |
664 | ||
665 | Float_t paramScaler; | |
666 | Float_t directedScaller = 1., ellipticScaller = 1.; | |
667 | ||
668 | TLorentzVector *v = new TLorentzVector(0,0,0,0); | |
669 | ||
670 | const Int_t kParent = -1; | |
671 | Int_t id; | |
672 | ||
673 | // vertexing | |
674 | VertexInternal(); | |
675 | orgin[0] = fVertex[0]; | |
676 | orgin[1] = fVertex[1]; | |
677 | orgin[2] = fVertex[2]; | |
678 | ||
679 | ||
680 | // Particle params database | |
681 | ||
682 | TDatabasePDG *db = TDatabasePDG::Instance(); | |
683 | TParticlePDG *type; | |
684 | AliGeVSimParticle *partType; | |
685 | ||
686 | Int_t nType, nParticle, nParam; | |
687 | const Int_t nParams = 6; | |
688 | ||
689 | // reaction plane determination and model | |
690 | DetermineReactionPlane(); | |
691 | ||
692 | // loop over particle types | |
693 | ||
694 | for (nType = 0; nType < fPartTypes->GetEntries(); nType++) { | |
695 | ||
696 | partType = (AliGeVSimParticle *)fPartTypes->At(nType); | |
697 | ||
698 | pdg = (PDG_t)partType->GetPdgCode(); | |
699 | type = db->GetParticle(pdg); | |
700 | mass = type->Mass(); | |
701 | ||
702 | fModel = partType->GetModel(); | |
703 | SetFormula(pdg); | |
704 | fCurrentForm->SetParameter("mass", mass); | |
705 | ||
706 | ||
707 | // Evaluation of parameters - loop over parameters | |
708 | ||
709 | for (nParam = 0; nParam < nParams; nParam++) { | |
710 | ||
711 | paramScaler = FindScaler(nParam, pdg); | |
712 | ||
713 | if (nParam == 0) | |
714 | fCurrentForm->SetParameter("temperature", paramScaler * partType->GetTemperature()); | |
715 | ||
716 | if (nParam == 1 && fModel == 1) | |
717 | fYFormula->SetParameter("sigmaY", paramScaler * partType->GetSigmaY()); | |
718 | ||
719 | if (nParam == 2 && fModel == 4) { | |
720 | ||
721 | Double_t totalExpVal = paramScaler * partType->GetExpansionVelocity(); | |
722 | ||
723 | if (totalExpVal == 0.0) totalExpVal = 0.0001; | |
724 | if (totalExpVal == 1.0) totalExpVal = 9.9999; | |
725 | ||
726 | fCurrentForm->SetParameter("expVel", totalExpVal); | |
727 | } | |
728 | ||
729 | // flow | |
730 | ||
731 | if (nParam == 3) directedScaller = paramScaler; | |
732 | if (nParam == 4) ellipticScaller = paramScaler; | |
733 | ||
734 | // multiplicity | |
735 | ||
736 | if (nParam == 5) { | |
737 | ||
738 | if (partType->IsMultForced()) isMultTotal = partType->IsMultTotal(); | |
739 | else isMultTotal = fIsMultTotal; | |
740 | ||
741 | multiplicity = paramScaler * partType->GetMultiplicity(); | |
742 | multiplicity *= (isMultTotal)? 1 : GetdNdYToTotal(); | |
743 | } | |
744 | } | |
745 | ||
746 | // Flow defined on the particle type level (not parameterised) | |
747 | if (partType->IsFlowSimple()) { | |
748 | fPhiFormula->SetParameter(1, partType->GetDirectedFlow(0,0) * directedScaller); | |
749 | fPhiFormula->SetParameter(2, partType->GetEllipticFlow(0,0) * ellipticScaller); | |
750 | } | |
751 | ||
752 | AdjustFormula(); | |
753 | ||
754 | ||
755 | Info("Generate","PDG = %d \t Mult = %d", pdg, (Int_t)multiplicity); | |
756 | ||
757 | // loop over particles | |
758 | ||
759 | nParticle = 0; | |
760 | while (nParticle < multiplicity) { | |
761 | ||
762 | Double_t pt, y, phi; // momentum in [pt,y,phi] | |
763 | Float_t p[3] = {0,0,0}; // particle momentum | |
764 | ||
765 | GetRandomPtY(pt, y); | |
766 | ||
767 | // phi distribution configuration when differential flow defined | |
768 | // to be optimised in future release | |
769 | ||
770 | if (!partType->IsFlowSimple()) { | |
771 | fPhiFormula->SetParameter(1, partType->GetDirectedFlow(pt,y) * directedScaller); | |
772 | fPhiFormula->SetParameter(2, partType->GetEllipticFlow(pt,y) * ellipticScaller); | |
773 | } | |
774 | ||
775 | phi = fPhiFormula->GetRandom(); | |
776 | ||
777 | if (!isMultTotal) nParticle++; | |
778 | if (fModel > 4 && !CheckPtYPhi(pt,y,phi) ) continue; | |
779 | ||
780 | // coordinate transformation | |
781 | v->SetPtEtaPhiM(pt, y, phi, mass); | |
782 | ||
783 | p[0] = v->Px(); | |
784 | p[1] = v->Py(); | |
785 | p[2] = v->Pz(); | |
786 | ||
787 | // momentum range test | |
788 | if ( !CheckAcceptance(p) ) continue; | |
789 | ||
790 | // putting particle on the stack | |
791 | ||
792 | SetTrack(fTrackIt, kParent, pdg, p, orgin, polar, time, kPPrimary, id, fTrackIt); | |
793 | if (isMultTotal) nParticle++; | |
794 | } | |
795 | } | |
796 | ||
797 | // prepare and store header | |
798 | ||
799 | AliGenGeVSimEventHeader *header = new AliGenGeVSimEventHeader("GeVSim header"); | |
800 | TArrayF eventVertex(3,orgin); | |
801 | ||
802 | header->SetPrimaryVertex(eventVertex); | |
803 | header->SetEventPlane(fPsi); | |
804 | header->SetEllipticFlow(fPhiFormula->GetParameter(2)); | |
805 | ||
806 | gAlice->SetGenEventHeader(header); | |
807 | ||
808 | delete v; | |
809 | } | |
810 | ||
811 | ////////////////////////////////////////////////////////////////////////////////// |