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Removal of useless dependecies via forward declarations
[u/mrichter/AliRoot.git] / EVGEN / AliGenHIJINGpara.cxx
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790bbabf 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/*
17$Log$
94de3818 18Revision 1.2 2000/07/11 18:24:55 fca
19Coding convention corrections + few minor bug fixes
20
aee8290b 21Revision 1.1 2000/06/09 20:20:30 morsch
22Same class as previously in AliSimpleGen.cxx
23All coding rule violations except RS3 corrected (AM)
24
790bbabf 25*/
26///////////////////////////////////////////////////////////////////
27// //
28// Generate the final state of the interaction as the input //
29// to the MonteCarlo //
30//
31//Begin_Html
32/*
33<img src="picts/AliGeneratorClass.gif">
34</pre>
35<br clear=left>
36<font size=+2 color=red>
37<p>The responsible person for this module is
38<a href="mailto:andreas.morsch@cern.ch">Andreas Morsch</a>.
39</font>
40<pre>
41*/
42//End_Html
43// //
44///////////////////////////////////////////////////////////////////
45
46#include "AliGenHIJINGpara.h"
47#include "AliRun.h"
94de3818 48#include "AliMC.h"
790bbabf 49#include "AliConst.h"
50#include "AliPDG.h"
51
52ClassImp(AliGenHIJINGpara)
53
54AliGenHIJINGpara::AliGenHIJINGpara(const AliGenHIJINGpara & para)
55{
56// copy constructor
57}
58
59//_____________________________________________________________________________
60static Double_t ptpi(Double_t *px, Double_t *)
61{
62 //
63 // PT-PARAMETERIZATION CDF, PRL 61(88) 1819
64 // POWER LAW FOR PT > 500 MEV
65 // MT SCALING BELOW (T=160 MEV)
66 //
67 const Double_t kp0 = 1.3;
68 const Double_t kxn = 8.28;
69 const Double_t kxlim=0.5;
70 const Double_t kt=0.160;
71 const Double_t kxmpi=0.139;
72 const Double_t kb=1.;
73 Double_t y, y1, xmpi2, ynorm, a;
74 Double_t x=*px;
75 //
76 y1=TMath::Power(kp0/(kp0+kxlim),kxn);
77 xmpi2=kxmpi*kxmpi;
78 ynorm=kb*(TMath::Exp(-sqrt(kxlim*kxlim+xmpi2)/kt));
79 a=ynorm/y1;
80 if (x > kxlim)
81 y=a*TMath::Power(kp0/(kp0+x),kxn);
82 else
83 y=kb*TMath::Exp(-sqrt(x*x+xmpi2)/kt);
84 return y*x;
85}
86
87//_____________________________________________________________________________
88static Double_t ptscal(Double_t pt, Int_t np)
89{
90 // SCALING EN MASSE PAR RAPPORT A PTPI
91 // MASS PI,K,ETA,RHO,OMEGA,ETA',PHI
92 const Double_t khm[10] = {.13957,.493,.5488,.769,.7826,.958,1.02,0,0,0};
93 // VALUE MESON/PI AT 5 GEV
94 const Double_t kfmax[10]={1.,0.3,0.55,1.0,1.0,1.0,1.0,0,0,0};
95 np--;
96 Double_t f5=TMath::Power(((
97 sqrt(100.018215)+2.)/(sqrt(100.+khm[np]*khm[np])+2.0)),12.3);
98 Double_t fmax2=f5/kfmax[np];
99 // PIONS
100 Double_t ptpion=100.*ptpi(&pt, (Double_t*) 0);
101 Double_t fmtscal=TMath::Power(((
102 sqrt(pt*pt+0.018215)+2.)/ (sqrt(pt*pt+khm[np]*khm[np])+2.0)),12.3)/
103 fmax2;
104 return fmtscal*ptpion;
105}
106
107//_____________________________________________________________________________
108static Double_t ptka( Double_t *px, Double_t *)
109{
110 //
111 // pt parametrisation for k
112 //
113 return ptscal(*px,2);
114}
115
116
117//_____________________________________________________________________________
118static Double_t etapic( Double_t *py, Double_t *)
119{
120 //
121 // eta parametrisation for pi
122 //
123 const Double_t ka1 = 4913.;
124 const Double_t ka2 = 1819.;
125 const Double_t keta1 = 0.22;
126 const Double_t keta2 = 3.66;
127 const Double_t kdeta1 = 1.47;
128 const Double_t kdeta2 = 1.51;
129 Double_t y=TMath::Abs(*py);
130 //
131 Double_t ex1 = (y-keta1)*(y-keta1)/(2*kdeta1*kdeta1);
132 Double_t ex2 = (y-keta2)*(y-keta2)/(2*kdeta2*kdeta2);
133 return ka1*TMath::Exp(-ex1)+ka2*TMath::Exp(-ex2);
134}
135
136//_____________________________________________________________________________
137static Double_t etakac( Double_t *py, Double_t *)
138{
139 //
140 // eta parametrisation for ka
141 //
142 const Double_t ka1 = 497.6;
143 const Double_t ka2 = 215.6;
144 const Double_t keta1 = 0.79;
145 const Double_t keta2 = 4.09;
146 const Double_t kdeta1 = 1.54;
147 const Double_t kdeta2 = 1.40;
148 Double_t y=TMath::Abs(*py);
149 //
150 Double_t ex1 = (y-keta1)*(y-keta1)/(2*kdeta1*kdeta1);
151 Double_t ex2 = (y-keta2)*(y-keta2)/(2*kdeta2*kdeta2);
152 return ka1*TMath::Exp(-ex1)+ka2*TMath::Exp(-ex2);
153}
154
155//_____________________________________________________________________________
156AliGenHIJINGpara::AliGenHIJINGpara()
157 :AliGenerator()
158{
159 //
160 // Default constructor
161 //
162 fPtpi = 0;
163 fPtka = 0;
164 fETApic = 0;
165 fETAkac = 0;
166}
167
168//_____________________________________________________________________________
169AliGenHIJINGpara::AliGenHIJINGpara(Int_t npart)
170 :AliGenerator(npart)
171{
172 //
173 // Standard constructor
174 //
175 fName="HIGINGpara";
176 fTitle="HIJING Parametrisation Particle Generator";
177 fPtpi = 0;
178 fPtka = 0;
179 fETApic = 0;
180 fETAkac = 0;
181}
182
183//_____________________________________________________________________________
184AliGenHIJINGpara::~AliGenHIJINGpara()
185{
186 //
187 // Standard destructor
188 //
189 delete fPtpi;
190 delete fPtka;
191 delete fETApic;
192 delete fETAkac;
193}
194
195//_____________________________________________________________________________
196void AliGenHIJINGpara::Init()
197{
198 //
199 // Initialise the HIJING parametrisation
200 //
201 Float_t etaMin =-TMath::Log(TMath::Tan(
202 TMath::Min((Double_t)fThetaMax/2,TMath::Pi()/2-1.e-10)));
203 Float_t etaMax = -TMath::Log(TMath::Tan(
204 TMath::Max((Double_t)fThetaMin/2,1.e-10)));
205 fPtpi = new TF1("ptpi",&ptpi,0,20,0);
206 fPtka = new TF1("ptka",&ptka,0,20,0);
207 fETApic = new TF1("etapic",&etapic,etaMin,etaMax,0);
208 fETAkac = new TF1("etakac",&etakac,etaMin,etaMax,0);
209 TF1 *etaPic0 = new TF1("etapic",&etapic,-7,7,0);
210 TF1 *etaKac0 = new TF1("etakac",&etakac,-7,7,0);
211 Float_t intETApi = etaPic0->Integral(-0.5, 0.5);
212 Float_t intETAka = etaKac0->Integral(-0.5, 0.5);
213 Float_t scalePi=7316/(intETApi/1.5);
214 Float_t scaleKa= 684/(intETAka/2.0);
215
216 Float_t intPt = (0.877*etaPic0->Integral(0, 15)+
217 0.123*etaKac0->Integral(0, 15));
218 Float_t intPtSel = (0.877*etaPic0->Integral(fPtMin, fPtMax)+
219 0.123*etaKac0->Integral(fPtMin, fPtMax));
220 Float_t ptFrac = intPtSel/intPt;
221
222
223 Float_t intETASel = (scalePi*etaPic0->Integral(etaMin, etaMax)+
224 scaleKa*etaKac0->Integral(etaMin, etaMax));
225 Float_t phiFrac = (fPhiMax-fPhiMin)/2/TMath::Pi();
226 fParentWeight = Float_t(fNpart)/intETASel*ptFrac*phiFrac;
227
228 printf("\n The number of particles in the selected kinematic region corresponds to %f percent of a full event\n ", 100.*fParentWeight);
229
230}
231
232//_____________________________________________________________________________
233void AliGenHIJINGpara::Generate()
234{
235 //
236 // Generate one trigger
237 //
238
239
240 const Float_t kRaKpic=0.14;
241 const Float_t kBorne=1/(1+kRaKpic);
242 Float_t polar[3]= {0,0,0};
243 //
244 const Int_t kPions[3] = {kPi0, kPiPlus, kPiMinus};
245 const Int_t kKaons[4] = {kK0Long, kK0Short, kKPlus, kKMinus};
246 //
247 Float_t origin[3];
248 Float_t pt, pl, ptot;
249 Float_t phi, theta;
250 Float_t p[3];
251 Int_t i, part, nt, j;
252 //
253 TF1 *ptf;
254 TF1 *etaf;
255 //
256 Float_t random[6];
257 //
258 for (j=0;j<3;j++) origin[j]=fOrigin[j];
aee8290b 259 if(fVertexSmear==kPerEvent) {
790bbabf 260 gMC->Rndm(random,6);
261 for (j=0;j<3;j++) {
262 origin[j]+=fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
263 TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
264 }
265 }
266 for(i=0;i<fNpart;i++) {
267 while(1) {
268 gMC->Rndm(random,3);
269 if(random[0]<kBorne) {
270 part=kPions[Int_t (random[1]*3)];
271 ptf=fPtpi;
272 etaf=fETApic;
273 } else {
274 part=kKaons[Int_t (random[1]*4)];
275 ptf=fPtka;
276 etaf=fETAkac;
277 }
278 phi=fPhiMin+random[2]*(fPhiMax-fPhiMin);
279 theta=2*TMath::ATan(TMath::Exp(-etaf->GetRandom()));
280 if(theta<fThetaMin || theta>fThetaMax) continue;
281 pt=ptf->GetRandom();
282 pl=pt/TMath::Tan(theta);
283 ptot=TMath::Sqrt(pt*pt+pl*pl);
284 if(ptot<fPMin || ptot>fPMax) continue;
285 p[0]=pt*TMath::Cos(phi);
286 p[1]=pt*TMath::Sin(phi);
287 p[2]=pl;
aee8290b 288 if(fVertexSmear==kPerTrack) {
790bbabf 289 gMC->Rndm(random,6);
290 for (j=0;j<3;j++) {
291 origin[j]=fOrigin[j]+fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
292 TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
293 }
294 }
295 gAlice->SetTrack(fTrackIt,-1,part,p,origin,polar,0,"Primary",nt,fParentWeight);
296 break;
297 }
298 }
299}
300
301AliGenHIJINGpara& AliGenHIJINGpara::operator=(const AliGenHIJINGpara& rhs)
302{
303// Assignment operator
304 return *this;
305}
306
307