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Introduced PDG code everywhere and use of TParticlePDG.
[u/mrichter/AliRoot.git] / EVGEN / AliSimpleGen.cxx
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fe4da5cc 1///////////////////////////////////////////////////////////////////
2// //
3// Generate the final state of the interaction as the input //
4// to the MonteCarlo //
5//
6//Begin_Html
7/*
1439f98e 8<img src="picts/AliGeneratorClass.gif">
fe4da5cc 9</pre>
10<br clear=left>
11<font size=+2 color=red>
12<p>The responsible person for this module is
13<a href="mailto:andreas.morsch@cern.ch">Andreas Morsch</a>.
14</font>
15<pre>
16*/
17//End_Html
18// //
19///////////////////////////////////////////////////////////////////
20
21#include "AliSimpleGen.h"
22#include "AliRun.h"
1578254f 23#include "AliConst.h"
fe4da5cc 24
25ClassImp(AliGenHIJINGpara)
26
27//_____________________________________________________________________________
28static Double_t ptpi(Double_t *px, Double_t *)
29{
30 //
31 // PT-PARAMETERIZATION CDF, PRL 61(88) 1819
32 // POWER LAW FOR PT > 500 MEV
33 // MT SCALING BELOW (T=160 MEV)
34 //
35 const Double_t p0 = 1.3;
36 const Double_t xn = 8.28;
37 const Double_t xlim=0.5;
38 const Double_t t=0.160;
39 const Double_t xmpi=0.139;
40 const Double_t b=1.;
41 Double_t y, y1, xmpi2, ynorm, a;
42 Double_t x=*px;
43 //
44 y1=TMath::Power(p0/(p0+xlim),xn);
45 xmpi2=xmpi*xmpi;
46 ynorm=b*(TMath::Exp(-sqrt(xlim*xlim+xmpi2)/t));
47 a=ynorm/y1;
48 if (x > xlim)
49 y=a*TMath::Power(p0/(p0+x),xn);
50 else
51 y=b*TMath::Exp(-sqrt(x*x+xmpi2)/t);
52 return y*x;
53}
54
55//_____________________________________________________________________________
56static Double_t ptscal(Double_t pt, Int_t np)
57{
58 // SCALING EN MASSE PAR RAPPORT A PTPI
59 // MASS PI,K,ETA,RHO,OMEGA,ETA',PHI
60 const Double_t hm[10] = {.13957,.493,.5488,.769,.7826,.958,1.02,0,0,0};
61 // VALUE MESON/PI AT 5 GEV
62 const Double_t fmax[10]={1.,0.3,0.55,1.0,1.0,1.0,1.0,0,0,0};
63 np--;
64 Double_t f5=TMath::Power(((sqrt(100.018215)+2.)/(sqrt(100.+hm[np]*hm[np])+2.0)),12.3);
65 Double_t fmax2=f5/fmax[np];
66 // PIONS
67 Double_t ptpion=100.*ptpi(&pt, (Double_t*) 0);
68 Double_t fmtscal=TMath::Power(((sqrt(pt*pt+0.018215)+2.)/
69 (sqrt(pt*pt+hm[np]*hm[np])+2.0)),12.3)/ fmax2;
70 return fmtscal*ptpion;
71}
72
73//_____________________________________________________________________________
74static Double_t ptka( Double_t *px, Double_t *)
75{
76 //
77 // pt parametrisation for k
78 //
79 return ptscal(*px,2);
80}
81
82
83//_____________________________________________________________________________
84static Double_t etapic( Double_t *py, Double_t *)
85{
86 //
87 // eta parametrisation for pi
88 //
89 const Double_t a1 = 4913.;
90 const Double_t a2 = 1819.;
91 const Double_t eta1 = 0.22;
92 const Double_t eta2 = 3.66;
93 const Double_t deta1 = 1.47;
94 const Double_t deta2 = 1.51;
95 Double_t y=TMath::Abs(*py);
96 //
97 Double_t ex1 = (y-eta1)*(y-eta1)/(2*deta1*deta1);
98 Double_t ex2 = (y-eta2)*(y-eta2)/(2*deta2*deta2);
99 return a1*TMath::Exp(-ex1)+a2*TMath::Exp(-ex2);
100}
101
102//_____________________________________________________________________________
103static Double_t etakac( Double_t *py, Double_t *)
104{
105 //
106 // eta parametrisation for ka
107 //
108 const Double_t a1 = 497.6;
109 const Double_t a2 = 215.6;
110 const Double_t eta1 = 0.79;
111 const Double_t eta2 = 4.09;
112 const Double_t deta1 = 1.54;
113 const Double_t deta2 = 1.40;
114 Double_t y=TMath::Abs(*py);
115 //
116 Double_t ex1 = (y-eta1)*(y-eta1)/(2*deta1*deta1);
117 Double_t ex2 = (y-eta2)*(y-eta2)/(2*deta2*deta2);
118 return a1*TMath::Exp(-ex1)+a2*TMath::Exp(-ex2);
119}
120
121//_____________________________________________________________________________
122AliGenHIJINGpara::AliGenHIJINGpara()
123 :AliGenerator()
124{
125 //
126 // Default constructor
127 //
128 fPtpi = 0;
129 fPtka = 0;
130 fETApic = 0;
131 fETAkac = 0;
132}
133
134//_____________________________________________________________________________
135AliGenHIJINGpara::AliGenHIJINGpara(Int_t npart)
136 :AliGenerator(npart)
137{
138 //
139 // Standard constructor
140 //
141 fName="HIGINGpara";
142 fTitle="HIJING Parametrisation Particle Generator";
143 fPtpi = 0;
144 fPtka = 0;
145 fETApic = 0;
146 fETAkac = 0;
147}
148
149//_____________________________________________________________________________
150AliGenHIJINGpara::~AliGenHIJINGpara()
151{
152 //
153 // Standard destructor
154 //
155 delete fPtpi;
156 delete fPtka;
157 delete fETApic;
158 delete fETAkac;
159}
160
161//_____________________________________________________________________________
162void AliGenHIJINGpara::Init()
163{
164 //
165 // Initialise the HIJING parametrisation
166 //
167 Float_t etaMin = -TMath::Log(TMath::Tan(TMath::Min((Double_t)fThetaMax/2,TMath::Pi()/2-1.e-10)));
168 Float_t etaMax = -TMath::Log(TMath::Tan(TMath::Max((Double_t)fThetaMin/2, 1.e-10)));
169 fPtpi = new TF1("ptpi",&ptpi,0,20,0);
170 fPtka = new TF1("ptka",&ptka,0,20,0);
171 fETApic = new TF1("etapic",&etapic,etaMin,etaMax,0);
172 fETAkac = new TF1("etakac",&etakac,etaMin,etaMax,0);
173 TF1 *ETApic0 = new TF1("etapic",&etapic,-7,7,0);
174 TF1 *ETAkac0 = new TF1("etakac",&etakac,-7,7,0);
175 Float_t IntETApi = ETApic0->Integral(-0.5, 0.5);
176 Float_t IntETAka = ETAkac0->Integral(-0.5, 0.5);
177 Float_t scalePi=7316/(IntETApi/1.5);
178 Float_t scaleKa= 684/(IntETAka/2.0);
179
180 Float_t IntPt = (0.877*ETApic0->Integral(0, 15)+
181 0.123*ETAkac0->Integral(0, 15));
182 Float_t IntPtSel = (0.877*ETApic0->Integral(fPtMin, fPtMax)+
183 0.123*ETAkac0->Integral(fPtMin, fPtMax));
184 Float_t PtFrac = IntPtSel/IntPt;
185
186
187 Float_t IntETASel = (scalePi*ETApic0->Integral(etaMin, etaMax)+
188 scaleKa*ETAkac0->Integral(etaMin, etaMax));
189 Float_t PhiFrac = (fPhiMax-fPhiMin)/2/TMath::Pi();
190 fParentWeight = Float_t(fNpart)/IntETASel*PtFrac*PhiFrac;
191
192 printf("\n The number of particles in the selected kinematic region corresponds to %f percent of a full event\n ", 100.*fParentWeight);
193
194}
195
196//_____________________________________________________________________________
197void AliGenHIJINGpara::Generate()
198{
199 //
200 // Generate one trigger
201 //
202
203 AliMC* pMC = AliMC::GetMC();
204
205 const Float_t raKpic=0.14;
206 const Float_t borne=1/(1+raKpic);
207 Float_t polar[3]= {0,0,0};
208 //
1578254f 209 const Int_t pions[3] = {kPi0, kPiPlus, kPiMinus};
210 const Int_t kaons[4] = {kK0Long, kK0Short, kKPlus, kKMinus};
fe4da5cc 211 //
212 Float_t origin[3];
213 Float_t pt, pl, ptot;
214 Float_t phi, theta;
215 Float_t p[3];
216 Int_t i, part, nt, j;
217 //
218 TF1 *ptf;
219 TF1 *etaf;
220 //
221 Float_t random[6];
222 //
223 for (j=0;j<3;j++) origin[j]=fOrigin[j];
224 if(fVertexSmear==perEvent) {
225 pMC->Rndm(random,6);
226 for (j=0;j<3;j++) {
227 origin[j]+=fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
228 TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
229 }
230 }
231 for(i=0;i<fNpart;i++) {
232 while(1) {
233 pMC->Rndm(random,3);
234 if(random[0]<borne) {
235 part=pions[Int_t (random[1]*3)];
236 ptf=fPtpi;
237 etaf=fETApic;
238 } else {
239 part=kaons[Int_t (random[1]*4)];
240 ptf=fPtka;
241 etaf=fETAkac;
242 }
243 phi=2*random[2]*TMath::Pi();
244 if(phi<fPhiMin || phi>fPhiMax) continue;
245 theta=2*TMath::ATan(TMath::Exp(-etaf->GetRandom()));
246 if(theta<fThetaMin || theta>fThetaMax) continue;
247 pt=ptf->GetRandom();
248 pl=pt/TMath::Tan(theta);
249 ptot=TMath::Sqrt(pt*pt+pl*pl);
250 if(ptot<fPMin || ptot>fPMax) continue;
251 p[0]=pt*TMath::Cos(phi);
252 p[1]=pt*TMath::Sin(phi);
253 p[2]=pl;
254 if(fVertexSmear==perTrack) {
255 pMC->Rndm(random,6);
256 for (j=0;j<3;j++) {
257 origin[j]=fOrigin[j]+fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
258 TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
259 }
260 }
261 gAlice->SetTrack(1,-1,part,p,origin,polar,0,"Primary",nt,fParentWeight);
262 break;
263 }
264 }
265}
266
267ClassImp(AliGenFixed)
268
269//_____________________________________________________________________________
270AliGenFixed::AliGenFixed()
271 :AliGenerator()
272{
273 //
274 // Default constructor
275 //
276 fIpart = 0;
277}
278
279//_____________________________________________________________________________
280AliGenFixed::AliGenFixed(Int_t npart)
281 :AliGenerator(npart)
282{
283 //
284 // Standard constructor
285 //
286 fName="Fixed";
287 fTitle="Fixed Particle Generator";
288 // Generate Proton by default
1578254f 289 fIpart=kProton;
fe4da5cc 290}
291
292//_____________________________________________________________________________
293void AliGenFixed::Generate()
294{
295 //
296 // Generate one trigger
297 //
298 Float_t polar[3]= {0,0,0};
299 Float_t p[3] = {fPMin*TMath::Cos(fPhiMin)*TMath::Sin(fThetaMin),
300 fPMin*TMath::Sin(fPhiMin)*TMath::Sin(fThetaMin),
301 fPMin*TMath::Cos(fThetaMin)};
302 Int_t i, nt;
303 //
304 for(i=0;i<fNpart;i++) {
305 gAlice->SetTrack(1,-1,fIpart,p,fOrigin.GetArray(),polar,0,"Primary",nt);
306 }
307}
308
309//_____________________________________________________________________________
310void AliGenFixed::SetSigma(Float_t, Float_t, Float_t)
311{
312 //
313 // Set the interaction point sigma
314 //
315 printf("Vertex smearing not implemented for fixed generator\n");
316}
317
318
319ClassImp(AliGenBox)
320
321//_____________________________________________________________________________
322AliGenBox::AliGenBox()
323 :AliGenerator()
324{
325 //
326 // Default constructor
327 //
328 fIpart=0;
329}
330
331//_____________________________________________________________________________
332AliGenBox::AliGenBox(Int_t npart)
333 :AliGenerator(npart)
334{
335 //
336 // Standard constructor
337 //
338 fName="Box";
339 fTitle="Box particle generator";
340 // Generate Proton by default
1578254f 341 fIpart=kProton;
fe4da5cc 342}
343
344//_____________________________________________________________________________
345void AliGenBox::Generate()
346{
347 //
348 // Generate one trigger
349 //
350 AliMC* pMC = AliMC::GetMC();
351
352 Float_t polar[3]= {0,0,0};
353 //
354 Float_t origin[3];
355 Float_t p[3];
356 Int_t i, j, nt;
357 Float_t pmom, theta, phi;
358 //
359 Float_t random[6];
360 //
361 for (j=0;j<3;j++) origin[j]=fOrigin[j];
362 if(fVertexSmear==perEvent) {
363 pMC->Rndm(random,6);
364 for (j=0;j<3;j++) {
365 origin[j]+=fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
366 TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
367 }
368 }
369 for(i=0;i<fNpart;i++) {
370 pMC->Rndm(random,3);
371 pmom=fPMin+random[0]*(fPMax-fPMin);
372 theta=fThetaMin+random[1]*(fThetaMax-fThetaMin);
373 phi=fPhiMin+random[2]*(fPhiMax-fPhiMin);
374 p[0] = pmom*TMath::Cos(phi)*TMath::Sin(theta);
375 p[1] = pmom*TMath::Sin(phi)*TMath::Sin(theta);
376 p[2] = pmom*TMath::Cos(theta);
377 if(fVertexSmear==perTrack) {
378 pMC->Rndm(random,6);
379 for (j=0;j<3;j++) {
380 origin[j]=fOrigin[j]+fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
381 TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
382 }
383 }
384 gAlice->SetTrack(1,-1,fIpart,p,origin,polar,0,"Primary",nt);
385 }
386}
387
388