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Correcting coding convention violations
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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$Log$
65fb704d 18Revision 1.3 2000/10/02 21:28:06 fca
19Removal of useless dependecies via forward declarations
20
94de3818 21Revision 1.2 2000/07/11 18:24:55 fca
22Coding convention corrections + few minor bug fixes
23
aee8290b 24Revision 1.1 2000/06/09 20:20:30 morsch
25Same class as previously in AliSimpleGen.cxx
26All coding rule violations except RS3 corrected (AM)
27
790bbabf 28*/
29///////////////////////////////////////////////////////////////////
30// //
31// Generate the final state of the interaction as the input //
32// to the MonteCarlo //
33//
34//Begin_Html
35/*
36<img src="picts/AliGeneratorClass.gif">
37</pre>
38<br clear=left>
39<font size=+2 color=red>
40<p>The responsible person for this module is
41<a href="mailto:andreas.morsch@cern.ch">Andreas Morsch</a>.
42</font>
43<pre>
44*/
45//End_Html
46// //
47///////////////////////////////////////////////////////////////////
48
49#include "AliGenHIJINGpara.h"
65fb704d 50#include "TF1.h"
790bbabf 51#include "AliRun.h"
52#include "AliConst.h"
53#include "AliPDG.h"
54
55ClassImp(AliGenHIJINGpara)
56
57AliGenHIJINGpara::AliGenHIJINGpara(const AliGenHIJINGpara & para)
58{
59// copy constructor
60}
61
62//_____________________________________________________________________________
63static Double_t ptpi(Double_t *px, Double_t *)
64{
65 //
66 // PT-PARAMETERIZATION CDF, PRL 61(88) 1819
67 // POWER LAW FOR PT > 500 MEV
68 // MT SCALING BELOW (T=160 MEV)
69 //
70 const Double_t kp0 = 1.3;
71 const Double_t kxn = 8.28;
72 const Double_t kxlim=0.5;
73 const Double_t kt=0.160;
74 const Double_t kxmpi=0.139;
75 const Double_t kb=1.;
76 Double_t y, y1, xmpi2, ynorm, a;
77 Double_t x=*px;
78 //
79 y1=TMath::Power(kp0/(kp0+kxlim),kxn);
80 xmpi2=kxmpi*kxmpi;
81 ynorm=kb*(TMath::Exp(-sqrt(kxlim*kxlim+xmpi2)/kt));
82 a=ynorm/y1;
83 if (x > kxlim)
84 y=a*TMath::Power(kp0/(kp0+x),kxn);
85 else
86 y=kb*TMath::Exp(-sqrt(x*x+xmpi2)/kt);
87 return y*x;
88}
89
90//_____________________________________________________________________________
91static Double_t ptscal(Double_t pt, Int_t np)
92{
93 // SCALING EN MASSE PAR RAPPORT A PTPI
94 // MASS PI,K,ETA,RHO,OMEGA,ETA',PHI
95 const Double_t khm[10] = {.13957,.493,.5488,.769,.7826,.958,1.02,0,0,0};
96 // VALUE MESON/PI AT 5 GEV
97 const Double_t kfmax[10]={1.,0.3,0.55,1.0,1.0,1.0,1.0,0,0,0};
98 np--;
99 Double_t f5=TMath::Power(((
100 sqrt(100.018215)+2.)/(sqrt(100.+khm[np]*khm[np])+2.0)),12.3);
101 Double_t fmax2=f5/kfmax[np];
102 // PIONS
103 Double_t ptpion=100.*ptpi(&pt, (Double_t*) 0);
104 Double_t fmtscal=TMath::Power(((
105 sqrt(pt*pt+0.018215)+2.)/ (sqrt(pt*pt+khm[np]*khm[np])+2.0)),12.3)/
106 fmax2;
107 return fmtscal*ptpion;
108}
109
110//_____________________________________________________________________________
111static Double_t ptka( Double_t *px, Double_t *)
112{
113 //
114 // pt parametrisation for k
115 //
116 return ptscal(*px,2);
117}
118
119
120//_____________________________________________________________________________
121static Double_t etapic( Double_t *py, Double_t *)
122{
123 //
124 // eta parametrisation for pi
125 //
126 const Double_t ka1 = 4913.;
127 const Double_t ka2 = 1819.;
128 const Double_t keta1 = 0.22;
129 const Double_t keta2 = 3.66;
130 const Double_t kdeta1 = 1.47;
131 const Double_t kdeta2 = 1.51;
132 Double_t y=TMath::Abs(*py);
133 //
134 Double_t ex1 = (y-keta1)*(y-keta1)/(2*kdeta1*kdeta1);
135 Double_t ex2 = (y-keta2)*(y-keta2)/(2*kdeta2*kdeta2);
136 return ka1*TMath::Exp(-ex1)+ka2*TMath::Exp(-ex2);
137}
138
139//_____________________________________________________________________________
140static Double_t etakac( Double_t *py, Double_t *)
141{
142 //
143 // eta parametrisation for ka
144 //
145 const Double_t ka1 = 497.6;
146 const Double_t ka2 = 215.6;
147 const Double_t keta1 = 0.79;
148 const Double_t keta2 = 4.09;
149 const Double_t kdeta1 = 1.54;
150 const Double_t kdeta2 = 1.40;
151 Double_t y=TMath::Abs(*py);
152 //
153 Double_t ex1 = (y-keta1)*(y-keta1)/(2*kdeta1*kdeta1);
154 Double_t ex2 = (y-keta2)*(y-keta2)/(2*kdeta2*kdeta2);
155 return ka1*TMath::Exp(-ex1)+ka2*TMath::Exp(-ex2);
156}
157
158//_____________________________________________________________________________
159AliGenHIJINGpara::AliGenHIJINGpara()
160 :AliGenerator()
161{
162 //
163 // Default constructor
164 //
165 fPtpi = 0;
166 fPtka = 0;
167 fETApic = 0;
168 fETAkac = 0;
169}
170
171//_____________________________________________________________________________
172AliGenHIJINGpara::AliGenHIJINGpara(Int_t npart)
173 :AliGenerator(npart)
174{
175 //
176 // Standard constructor
177 //
178 fName="HIGINGpara";
179 fTitle="HIJING Parametrisation Particle Generator";
180 fPtpi = 0;
181 fPtka = 0;
182 fETApic = 0;
183 fETAkac = 0;
184}
185
186//_____________________________________________________________________________
187AliGenHIJINGpara::~AliGenHIJINGpara()
188{
189 //
190 // Standard destructor
191 //
192 delete fPtpi;
193 delete fPtka;
194 delete fETApic;
195 delete fETAkac;
196}
197
198//_____________________________________________________________________________
199void AliGenHIJINGpara::Init()
200{
201 //
202 // Initialise the HIJING parametrisation
203 //
204 Float_t etaMin =-TMath::Log(TMath::Tan(
205 TMath::Min((Double_t)fThetaMax/2,TMath::Pi()/2-1.e-10)));
206 Float_t etaMax = -TMath::Log(TMath::Tan(
207 TMath::Max((Double_t)fThetaMin/2,1.e-10)));
208 fPtpi = new TF1("ptpi",&ptpi,0,20,0);
209 fPtka = new TF1("ptka",&ptka,0,20,0);
210 fETApic = new TF1("etapic",&etapic,etaMin,etaMax,0);
211 fETAkac = new TF1("etakac",&etakac,etaMin,etaMax,0);
212 TF1 *etaPic0 = new TF1("etapic",&etapic,-7,7,0);
213 TF1 *etaKac0 = new TF1("etakac",&etakac,-7,7,0);
214 Float_t intETApi = etaPic0->Integral(-0.5, 0.5);
215 Float_t intETAka = etaKac0->Integral(-0.5, 0.5);
216 Float_t scalePi=7316/(intETApi/1.5);
217 Float_t scaleKa= 684/(intETAka/2.0);
218
219 Float_t intPt = (0.877*etaPic0->Integral(0, 15)+
220 0.123*etaKac0->Integral(0, 15));
221 Float_t intPtSel = (0.877*etaPic0->Integral(fPtMin, fPtMax)+
222 0.123*etaKac0->Integral(fPtMin, fPtMax));
223 Float_t ptFrac = intPtSel/intPt;
224
225
226 Float_t intETASel = (scalePi*etaPic0->Integral(etaMin, etaMax)+
227 scaleKa*etaKac0->Integral(etaMin, etaMax));
228 Float_t phiFrac = (fPhiMax-fPhiMin)/2/TMath::Pi();
229 fParentWeight = Float_t(fNpart)/intETASel*ptFrac*phiFrac;
230
231 printf("\n The number of particles in the selected kinematic region corresponds to %f percent of a full event\n ", 100.*fParentWeight);
232
233}
234
235//_____________________________________________________________________________
236void AliGenHIJINGpara::Generate()
237{
238 //
239 // Generate one trigger
240 //
241
242
243 const Float_t kRaKpic=0.14;
244 const Float_t kBorne=1/(1+kRaKpic);
245 Float_t polar[3]= {0,0,0};
246 //
247 const Int_t kPions[3] = {kPi0, kPiPlus, kPiMinus};
248 const Int_t kKaons[4] = {kK0Long, kK0Short, kKPlus, kKMinus};
249 //
250 Float_t origin[3];
251 Float_t pt, pl, ptot;
252 Float_t phi, theta;
253 Float_t p[3];
254 Int_t i, part, nt, j;
255 //
256 TF1 *ptf;
257 TF1 *etaf;
258 //
259 Float_t random[6];
260 //
261 for (j=0;j<3;j++) origin[j]=fOrigin[j];
aee8290b 262 if(fVertexSmear==kPerEvent) {
65fb704d 263 Rndm(random,6);
790bbabf 264 for (j=0;j<3;j++) {
265 origin[j]+=fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
266 TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
267 }
268 }
269 for(i=0;i<fNpart;i++) {
270 while(1) {
65fb704d 271 Rndm(random,3);
790bbabf 272 if(random[0]<kBorne) {
273 part=kPions[Int_t (random[1]*3)];
274 ptf=fPtpi;
275 etaf=fETApic;
276 } else {
277 part=kKaons[Int_t (random[1]*4)];
278 ptf=fPtka;
279 etaf=fETAkac;
280 }
281 phi=fPhiMin+random[2]*(fPhiMax-fPhiMin);
282 theta=2*TMath::ATan(TMath::Exp(-etaf->GetRandom()));
283 if(theta<fThetaMin || theta>fThetaMax) continue;
284 pt=ptf->GetRandom();
285 pl=pt/TMath::Tan(theta);
286 ptot=TMath::Sqrt(pt*pt+pl*pl);
287 if(ptot<fPMin || ptot>fPMax) continue;
288 p[0]=pt*TMath::Cos(phi);
289 p[1]=pt*TMath::Sin(phi);
290 p[2]=pl;
aee8290b 291 if(fVertexSmear==kPerTrack) {
65fb704d 292 Rndm(random,6);
790bbabf 293 for (j=0;j<3;j++) {
294 origin[j]=fOrigin[j]+fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
295 TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
296 }
297 }
65fb704d 298 gAlice->SetTrack(fTrackIt,-1,part,p,origin,polar,0,kPPrimary,nt,fParentWeight);
790bbabf 299 break;
300 }
301 }
302}
303
304AliGenHIJINGpara& AliGenHIJINGpara::operator=(const AliGenHIJINGpara& rhs)
305{
306// Assignment operator
307 return *this;
308}
309
310