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[u/mrichter/AliRoot.git] / EVGEN / AliGenParam.cxx
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4c039060 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$Log$
18*/
19
fe4da5cc 20#include "AliGenParam.h"
21#include "AliGenMUONlib.h"
22#include "AliRun.h"
fe4da5cc 23#include "AliPythia.h"
24#include <TDirectory.h>
25#include <TFile.h>
26#include <TTree.h>
27#include <stdlib.h>
1578254f 28#include <TParticle.h>
fe4da5cc 29
30ClassImp(AliGenParam)
31
32//------------------------------------------------------------
33
34 //Begin_Html
35 /*
1439f98e 36 <img src="picts/AliGenParam.gif">
fe4da5cc 37 */
38 //End_Html
39
40//____________________________________________________________
41//____________________________________________________________
42AliGenParam::AliGenParam()
43 :AliGenerator()
44{
45 fPtPara = 0;
46 fYPara = 0;
b7601ac4 47 fParam = jpsi_p;
48 fAnalog = analog;
21aaa175 49 SetCutOnChild();
fe4da5cc 50}
51
52//____________________________________________________________
b7601ac4 53AliGenParam::AliGenParam(Int_t npart, Param_t param)
fe4da5cc 54// Double_t (*PtPara)(Double_t*, Double_t*),
55// Double_t (*YPara) (Double_t* ,Double_t*))
56 :AliGenerator(npart)
57{
58 //
59 // fName="HMESONpara";
60 // fTitle="Heavy Mesons Parametrisation";
b7601ac4 61 fPtParaFunc = AliGenMUONlib::GetPt(param);
62 fYParaFunc = AliGenMUONlib::GetY(param);
63 fIpParaFunc = AliGenMUONlib::GetIp(param);
fe4da5cc 64
65 fPtPara = 0;
66 fYPara = 0;
b7601ac4 67 fParam = param;
68 fAnalog = analog;
fe4da5cc 69 fChildSelect.Set(5);
70 for (Int_t i=0; i<5; i++) fChildSelect[i]=0;
71 ForceDecay();
21aaa175 72 SetCutOnChild();
fe4da5cc 73}
74
75//____________________________________________________________
76AliGenParam::~AliGenParam()
77{
78 delete fPtPara;
79 delete fYPara;
80}
81
82//____________________________________________________________
83void AliGenParam::Init()
84{
85 SetMC(new AliPythia());
86 fPythia= (AliPythia*) fgMCEvGen;
87
88// End of the test !!!
89 //Begin_Html
90 /*
1439f98e 91 <img src="picts/AliGenParam.gif">
fe4da5cc 92 */
93 //End_Html
94
b7601ac4 95 fPtPara = new TF1("Pt-Parametrization",fPtParaFunc,fPtMin,fPtMax,0);
96 fYPara = new TF1("Y -Parametrization",fYParaFunc,fYMin,fYMax,0);
97 TF1* PtPara = new TF1("Pt-Parametrization",fPtParaFunc,0,15,0);
98 TF1* YPara = new TF1("Y -Parametrization",fYParaFunc,-6,6,0);
99
fe4da5cc 100//
101// dN/dy| y=0
102 Double_t y1=0;
103 Double_t y2=0;
104
105 fdNdy0=fYParaFunc(&y1,&y2);
106//
107// Integral over generation region
b7601ac4 108 Float_t IntYS = YPara ->Integral(fYMin, fYMax);
109 Float_t IntPt0 = PtPara->Integral(0,15);
110 Float_t IntPtS = PtPara->Integral(fPtMin,fPtMax);
fe4da5cc 111 Float_t PhiWgt=(fPhiMax-fPhiMin)/2./TMath::Pi();
82db6e43 112 if (fAnalog == analog) {
fe4da5cc 113 fYWgt = IntYS/fdNdy0;
114 fPtWgt = IntPtS/IntPt0;
115 fParentWeight = fYWgt*fPtWgt*PhiWgt/fNpart;
116 } else {
117 fYWgt = IntYS/fdNdy0;
118 fPtWgt = (fPtMax-fPtMin)/IntPt0;
119 fParentWeight = fYWgt*fPtWgt*PhiWgt/fNpart;
120 }
121//
122// particle decay related initialization
123 fPythia->DefineParticles();
124// semimuonic decays of charm and beauty
125 fPythia->ForceDecay(fForceDecay);
126//
127 switch (fForceDecay)
128 {
129 case semielectronic:
130 case dielectron:
131 case b_jpsi_dielectron:
132 case b_psip_dielectron:
133 fChildSelect[0]=11;
134 break;
135 case semimuonic:
136 case dimuon:
137 case b_jpsi_dimuon:
138 case b_psip_dimuon:
139 fChildSelect[0]=13;
140 break;
b7601ac4 141 case pitomu:
142 fChildSelect[0]=13;
143 break;
144 case katomu:
145 fChildSelect[0]=13;
146 break;
fe4da5cc 147 }
148
149}
150
151//____________________________________________________________
152void AliGenParam::Generate()
153{
154// Generate 'npart' of heavy mesons (J/Psi, upsilon or phi) in the
155// the desired theta, phi and momentum windows; Gaussian smearing
156// on the vertex is done if selected
157
fe4da5cc 158
21aaa175 159 //printf("Generate !!!!!!!!!!!!!\n");
160
fe4da5cc 161 Float_t polar[3]= {0,0,0};
162 //
163 Float_t origin[3], origin0[3];
164 Float_t pt, pl, ptot;
165 Float_t phi, theta;
21aaa175 166 Float_t p[3], pc[3], och[3], pch[10][3];
fe4da5cc 167 Float_t ty, xmt;
21aaa175 168 Int_t nt, i, j, kfch[10];
fe4da5cc 169 Float_t wgtp, wgtch;
170 Double_t dummy;
09fd3ea2 171 static TClonesArray *particles;
fe4da5cc 172 //
09fd3ea2 173 if(!particles) particles=new TClonesArray("TParticle",1000);
fe4da5cc 174 //
175 Float_t random[6];
176 for (j=0;j<3;j++) origin0[j]=fOrigin[j];
177 if(fVertexSmear==perEvent) {
cfce8870 178 gMC->Rndm(random,6);
fe4da5cc 179 for (j=0;j<3;j++) {
180 origin0[j]+=fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
181 TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
182 }
183 }
21aaa175 184 Int_t ipa=0;
185 while (ipa<fNpart) {
186 while(1) {
fe4da5cc 187//
188// particle type
189 Int_t Ipart = fIpParaFunc();
190 fChildWeight=(fPythia->GetBraPart(Ipart))*fParentWeight;
191 Float_t am=fPythia->GetPMAS(fPythia->LuComp(Ipart),1);
cfce8870 192 gMC->Rndm(random,2);
fe4da5cc 193//
194// phi
195 phi=fPhiMin+random[0]*(fPhiMax-fPhiMin);
196//
197// y
198 ty=Float_t(TMath::TanH(fYPara->GetRandom()));
199//
200// pT
82db6e43 201 if (fAnalog == analog) {
fe4da5cc 202 pt=fPtPara->GetRandom();
203 wgtp=fParentWeight;
204 wgtch=fChildWeight;
205 } else {
206 pt=fPtMin+random[1]*(fPtMax-fPtMin);
207 Double_t ptd=pt;
208 wgtp=fParentWeight*fPtParaFunc(& ptd, &dummy);
209 wgtch=fChildWeight*fPtParaFunc(& ptd, &dummy);
210 }
211 xmt=sqrt(pt*pt+am*am);
212 pl=xmt*ty/sqrt(1.-ty*ty);
213 theta=TMath::ATan2(pt,pl);
214 if(theta<fThetaMin || theta>fThetaMax) continue;
215 ptot=TMath::Sqrt(pt*pt+pl*pl);
216 if(ptot<fPMin || ptot>fPMax) continue;
217 p[0]=pt*TMath::Cos(phi);
218 p[1]=pt*TMath::Sin(phi);
219 p[2]=pl;
220 if(fVertexSmear==perTrack) {
cfce8870 221 gMC->Rndm(random,6);
fe4da5cc 222 for (j=0;j<3;j++) {
223 origin0[j]=
224 fOrigin[j]+fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
225 TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
226 }
227 }
fe4da5cc 228//
229// use lujet to decay particle
230
231 Float_t energy=TMath::Sqrt(ptot*ptot+am*am);
232 fPythia->DecayParticle(Ipart,energy,theta,phi);
21aaa175 233 // fPythia->LuList(1);
234
235
236 //printf("origin0 %f %f %f\n",origin0[0],origin0[1],origin0[2]);
237 //printf("fCutOnChild %d \n",fCutOnChild);
fe4da5cc 238//
239// select muons
21aaa175 240 Int_t np=fPythia->ImportParticles(particles,"All");
241 //printf("np %d \n",np);
242 Int_t ncsel=0;
243 for (i = 1; i<np; i++) {
1578254f 244 TParticle * iparticle = (TParticle *) particles->At(i);
245 Int_t kf = iparticle->GetPdgCode();
21aaa175 246 //printf("kf %d\n",kf);
fe4da5cc 247//
248// children
249 if (ChildSelected(TMath::Abs(kf)))
250 {
21aaa175 251 pc[0]=iparticle->Px();
252 pc[1]=iparticle->Py();
253 pc[2]=iparticle->Pz();
254 och[0]=origin0[0]+iparticle->Vx()/10;
255 och[1]=origin0[1]+iparticle->Vy()/10;
256 och[2]=origin0[2]+iparticle->Vz()/10;
257 if (fCutOnChild) {
258 Float_t PtChild=TMath::Sqrt(pc[0]*pc[0]+pc[1]*pc[1]);
259 Float_t PChild=TMath::Sqrt(PtChild*PtChild+pc[2]*pc[2]);
260 Float_t ThetaChild=TMath::ATan2(PtChild,pc[2]);
261 Float_t PhiChild=TMath::ATan2(pc[1],pc[0])+TMath::Pi();
11f6d36c 262 Bool_t childok =
263 ((PtChild > fPtMin && PtChild <fPtMax) &&
21aaa175 264 (PChild > fPMin && PChild <fPMax) &&
265 (ThetaChild>fThetaMin && ThetaChild<fThetaMax) &&
11f6d36c 266 (PhiChild > fPhiMin && PhiChild <fPhiMax));
267 if(childok)
21aaa175 268 {
269 pch[ncsel][0]=pc[0];
270 pch[ncsel][1]=pc[1];
271 pch[ncsel][2]=pc[2];
272 kfch[ncsel]=kf;
273 ncsel++;
274 } else {
275 ncsel=-1;
276 break;
277 } // child kine cuts
278 } else {
279 pch[ncsel][0]=pc[0];
280 pch[ncsel][1]=pc[1];
281 pch[ncsel][2]=pc[2];
282 kfch[ncsel]=kf;
283 ncsel++;
284 } // if child selection
fe4da5cc 285 } // select muon
286 } // decay particle loop
21aaa175 287 Int_t iparent;
288 if ((fCutOnChild && ncsel >0) || !fCutOnChild){
289 ipa++;
290//
291// parent
292 gAlice->
293 SetTrack(0,-1,Ipart,p,origin,polar,0,"Primary",nt,wgtp);
294 iparent=nt;
295
296 for (i=0; i< ncsel; i++) {
297 gAlice->SetTrack(fTrackIt,iparent,kfch[i],
298 &pch[i][0],och,polar,
299 0,"Decay",nt,wgtch);
300 gAlice->KeepTrack(nt);
301 }
302
303 } // kinematic selection
fe4da5cc 304 break;
21aaa175 305 } // while
fe4da5cc 306 } // event loop
307}
308
309Bool_t AliGenParam::ChildSelected(Int_t ip)
310{
311 for (Int_t i=0; i<5; i++)
312 {
313 if (fChildSelect[i]==ip) return kTRUE;
314 }
315 return kFALSE;
316}
317
1578254f 318Bool_t AliGenParam::KinematicSelection(TParticle *particle)
fe4da5cc 319{
1578254f 320 Float_t px=particle->Px();
321 Float_t py=particle->Py();
322 Float_t pz=particle->Pz();
fe4da5cc 323//
324// momentum cut
325 Float_t p=TMath::Sqrt(px*px+py*py+pz*pz);
326 if (p > fPMax || p < fPMin)
327 {
328// printf("\n failed p cut %f %f %f \n",p,fPMin,fPMax);
329 return kFALSE;
330 }
331 Float_t pt=TMath::Sqrt(px*px+py*py);
332
333//
334// theta cut
335 Float_t theta = Float_t(TMath::ATan2(Double_t(pt),Double_t(p)));
336 if (theta > fThetaMax || theta < fThetaMin)
337 {
338// printf("\n failed theta cut %f %f %f \n",theta,fThetaMin,fThetaMax);
339 return kFALSE;
340 }
341
342 return kTRUE;
343}
344
345
346
347