Small corrections from A.Morsch for weighted events handling
[u/mrichter/AliRoot.git] / EVGEN / AliGenParam.cxx
CommitLineData
fe4da5cc 1#include "AliGenParam.h"
2#include "AliGenMUONlib.h"
3#include "AliRun.h"
fe4da5cc 4#include "AliPythia.h"
5#include <TDirectory.h>
6#include <TFile.h>
7#include <TTree.h>
8#include <stdlib.h>
1578254f 9#include <TParticle.h>
fe4da5cc 10
11ClassImp(AliGenParam)
12
13//------------------------------------------------------------
14
15 //Begin_Html
16 /*
1439f98e 17 <img src="picts/AliGenParam.gif">
fe4da5cc 18 */
19 //End_Html
20
21//____________________________________________________________
22//____________________________________________________________
23AliGenParam::AliGenParam()
24 :AliGenerator()
25{
26 fPtPara = 0;
27 fYPara = 0;
b7601ac4 28 fParam = jpsi_p;
29 fAnalog = analog;
21aaa175 30 SetCutOnChild();
fe4da5cc 31}
32
33//____________________________________________________________
b7601ac4 34AliGenParam::AliGenParam(Int_t npart, Param_t param)
fe4da5cc 35// Double_t (*PtPara)(Double_t*, Double_t*),
36// Double_t (*YPara) (Double_t* ,Double_t*))
37 :AliGenerator(npart)
38{
39 //
40 // fName="HMESONpara";
41 // fTitle="Heavy Mesons Parametrisation";
b7601ac4 42 fPtParaFunc = AliGenMUONlib::GetPt(param);
43 fYParaFunc = AliGenMUONlib::GetY(param);
44 fIpParaFunc = AliGenMUONlib::GetIp(param);
fe4da5cc 45
46 fPtPara = 0;
47 fYPara = 0;
b7601ac4 48 fParam = param;
49 fAnalog = analog;
fe4da5cc 50 fChildSelect.Set(5);
51 for (Int_t i=0; i<5; i++) fChildSelect[i]=0;
52 ForceDecay();
21aaa175 53 SetCutOnChild();
fe4da5cc 54}
55
56//____________________________________________________________
57AliGenParam::~AliGenParam()
58{
59 delete fPtPara;
60 delete fYPara;
61}
62
63//____________________________________________________________
64void AliGenParam::Init()
65{
66 SetMC(new AliPythia());
67 fPythia= (AliPythia*) fgMCEvGen;
68
69// End of the test !!!
70 //Begin_Html
71 /*
1439f98e 72 <img src="picts/AliGenParam.gif">
fe4da5cc 73 */
74 //End_Html
75
b7601ac4 76 fPtPara = new TF1("Pt-Parametrization",fPtParaFunc,fPtMin,fPtMax,0);
77 fYPara = new TF1("Y -Parametrization",fYParaFunc,fYMin,fYMax,0);
78 TF1* PtPara = new TF1("Pt-Parametrization",fPtParaFunc,0,15,0);
79 TF1* YPara = new TF1("Y -Parametrization",fYParaFunc,-6,6,0);
80
fe4da5cc 81//
82// dN/dy| y=0
83 Double_t y1=0;
84 Double_t y2=0;
85
86 fdNdy0=fYParaFunc(&y1,&y2);
87//
88// Integral over generation region
b7601ac4 89 Float_t IntYS = YPara ->Integral(fYMin, fYMax);
90 Float_t IntPt0 = PtPara->Integral(0,15);
91 Float_t IntPtS = PtPara->Integral(fPtMin,fPtMax);
fe4da5cc 92 Float_t PhiWgt=(fPhiMax-fPhiMin)/2./TMath::Pi();
82db6e43 93 if (fAnalog == analog) {
fe4da5cc 94 fYWgt = IntYS/fdNdy0;
95 fPtWgt = IntPtS/IntPt0;
96 fParentWeight = fYWgt*fPtWgt*PhiWgt/fNpart;
97 } else {
98 fYWgt = IntYS/fdNdy0;
99 fPtWgt = (fPtMax-fPtMin)/IntPt0;
100 fParentWeight = fYWgt*fPtWgt*PhiWgt/fNpart;
101 }
102//
103// particle decay related initialization
104 fPythia->DefineParticles();
105// semimuonic decays of charm and beauty
106 fPythia->ForceDecay(fForceDecay);
107//
108 switch (fForceDecay)
109 {
110 case semielectronic:
111 case dielectron:
112 case b_jpsi_dielectron:
113 case b_psip_dielectron:
114 fChildSelect[0]=11;
115 break;
116 case semimuonic:
117 case dimuon:
118 case b_jpsi_dimuon:
119 case b_psip_dimuon:
120 fChildSelect[0]=13;
121 break;
b7601ac4 122 case pitomu:
123 fChildSelect[0]=13;
124 break;
125 case katomu:
126 fChildSelect[0]=13;
127 break;
fe4da5cc 128 }
129
130}
131
132//____________________________________________________________
133void AliGenParam::Generate()
134{
135// Generate 'npart' of heavy mesons (J/Psi, upsilon or phi) in the
136// the desired theta, phi and momentum windows; Gaussian smearing
137// on the vertex is done if selected
138
fe4da5cc 139
21aaa175 140 //printf("Generate !!!!!!!!!!!!!\n");
141
fe4da5cc 142 Float_t polar[3]= {0,0,0};
143 //
144 Float_t origin[3], origin0[3];
145 Float_t pt, pl, ptot;
146 Float_t phi, theta;
21aaa175 147 Float_t p[3], pc[3], och[3], pch[10][3];
fe4da5cc 148 Float_t ty, xmt;
21aaa175 149 Int_t nt, i, j, kfch[10];
fe4da5cc 150 Float_t wgtp, wgtch;
151 Double_t dummy;
09fd3ea2 152 static TClonesArray *particles;
fe4da5cc 153 //
09fd3ea2 154 if(!particles) particles=new TClonesArray("TParticle",1000);
fe4da5cc 155 //
156 Float_t random[6];
157 for (j=0;j<3;j++) origin0[j]=fOrigin[j];
158 if(fVertexSmear==perEvent) {
cfce8870 159 gMC->Rndm(random,6);
fe4da5cc 160 for (j=0;j<3;j++) {
161 origin0[j]+=fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
162 TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
163 }
164 }
21aaa175 165 Int_t ipa=0;
166 while (ipa<fNpart) {
167 while(1) {
fe4da5cc 168//
169// particle type
170 Int_t Ipart = fIpParaFunc();
171 fChildWeight=(fPythia->GetBraPart(Ipart))*fParentWeight;
172 Float_t am=fPythia->GetPMAS(fPythia->LuComp(Ipart),1);
cfce8870 173 gMC->Rndm(random,2);
fe4da5cc 174//
175// phi
176 phi=fPhiMin+random[0]*(fPhiMax-fPhiMin);
177//
178// y
179 ty=Float_t(TMath::TanH(fYPara->GetRandom()));
180//
181// pT
82db6e43 182 if (fAnalog == analog) {
fe4da5cc 183 pt=fPtPara->GetRandom();
184 wgtp=fParentWeight;
185 wgtch=fChildWeight;
186 } else {
187 pt=fPtMin+random[1]*(fPtMax-fPtMin);
188 Double_t ptd=pt;
189 wgtp=fParentWeight*fPtParaFunc(& ptd, &dummy);
190 wgtch=fChildWeight*fPtParaFunc(& ptd, &dummy);
191 }
192 xmt=sqrt(pt*pt+am*am);
193 pl=xmt*ty/sqrt(1.-ty*ty);
194 theta=TMath::ATan2(pt,pl);
195 if(theta<fThetaMin || theta>fThetaMax) continue;
196 ptot=TMath::Sqrt(pt*pt+pl*pl);
197 if(ptot<fPMin || ptot>fPMax) continue;
198 p[0]=pt*TMath::Cos(phi);
199 p[1]=pt*TMath::Sin(phi);
200 p[2]=pl;
201 if(fVertexSmear==perTrack) {
cfce8870 202 gMC->Rndm(random,6);
fe4da5cc 203 for (j=0;j<3;j++) {
204 origin0[j]=
205 fOrigin[j]+fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
206 TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
207 }
208 }
fe4da5cc 209//
210// use lujet to decay particle
211
212 Float_t energy=TMath::Sqrt(ptot*ptot+am*am);
213 fPythia->DecayParticle(Ipart,energy,theta,phi);
21aaa175 214 // fPythia->LuList(1);
215
216
217 //printf("origin0 %f %f %f\n",origin0[0],origin0[1],origin0[2]);
218 //printf("fCutOnChild %d \n",fCutOnChild);
fe4da5cc 219//
220// select muons
21aaa175 221 Int_t np=fPythia->ImportParticles(particles,"All");
222 //printf("np %d \n",np);
223 Int_t ncsel=0;
224 for (i = 1; i<np; i++) {
1578254f 225 TParticle * iparticle = (TParticle *) particles->At(i);
226 Int_t kf = iparticle->GetPdgCode();
21aaa175 227 //printf("kf %d\n",kf);
fe4da5cc 228//
229// children
230 if (ChildSelected(TMath::Abs(kf)))
231 {
21aaa175 232 pc[0]=iparticle->Px();
233 pc[1]=iparticle->Py();
234 pc[2]=iparticle->Pz();
235 och[0]=origin0[0]+iparticle->Vx()/10;
236 och[1]=origin0[1]+iparticle->Vy()/10;
237 och[2]=origin0[2]+iparticle->Vz()/10;
238 if (fCutOnChild) {
239 Float_t PtChild=TMath::Sqrt(pc[0]*pc[0]+pc[1]*pc[1]);
240 Float_t PChild=TMath::Sqrt(PtChild*PtChild+pc[2]*pc[2]);
241 Float_t ThetaChild=TMath::ATan2(PtChild,pc[2]);
242 Float_t PhiChild=TMath::ATan2(pc[1],pc[0])+TMath::Pi();
11f6d36c 243 Bool_t childok =
244 ((PtChild > fPtMin && PtChild <fPtMax) &&
21aaa175 245 (PChild > fPMin && PChild <fPMax) &&
246 (ThetaChild>fThetaMin && ThetaChild<fThetaMax) &&
11f6d36c 247 (PhiChild > fPhiMin && PhiChild <fPhiMax));
248 if(childok)
21aaa175 249 {
250 pch[ncsel][0]=pc[0];
251 pch[ncsel][1]=pc[1];
252 pch[ncsel][2]=pc[2];
253 kfch[ncsel]=kf;
254 ncsel++;
255 } else {
256 ncsel=-1;
257 break;
258 } // child kine cuts
259 } else {
260 pch[ncsel][0]=pc[0];
261 pch[ncsel][1]=pc[1];
262 pch[ncsel][2]=pc[2];
263 kfch[ncsel]=kf;
264 ncsel++;
265 } // if child selection
fe4da5cc 266 } // select muon
267 } // decay particle loop
21aaa175 268 Int_t iparent;
269 if ((fCutOnChild && ncsel >0) || !fCutOnChild){
270 ipa++;
271//
272// parent
273 gAlice->
274 SetTrack(0,-1,Ipart,p,origin,polar,0,"Primary",nt,wgtp);
275 iparent=nt;
276
277 for (i=0; i< ncsel; i++) {
278 gAlice->SetTrack(fTrackIt,iparent,kfch[i],
279 &pch[i][0],och,polar,
280 0,"Decay",nt,wgtch);
281 gAlice->KeepTrack(nt);
282 }
283
284 } // kinematic selection
fe4da5cc 285 break;
21aaa175 286 } // while
fe4da5cc 287 } // event loop
288}
289
290Bool_t AliGenParam::ChildSelected(Int_t ip)
291{
292 for (Int_t i=0; i<5; i++)
293 {
294 if (fChildSelect[i]==ip) return kTRUE;
295 }
296 return kFALSE;
297}
298
1578254f 299Bool_t AliGenParam::KinematicSelection(TParticle *particle)
fe4da5cc 300{
1578254f 301 Float_t px=particle->Px();
302 Float_t py=particle->Py();
303 Float_t pz=particle->Pz();
fe4da5cc 304//
305// momentum cut
306 Float_t p=TMath::Sqrt(px*px+py*py+pz*pz);
307 if (p > fPMax || p < fPMin)
308 {
309// printf("\n failed p cut %f %f %f \n",p,fPMin,fPMax);
310 return kFALSE;
311 }
312 Float_t pt=TMath::Sqrt(px*px+py*py);
313
314//
315// theta cut
316 Float_t theta = Float_t(TMath::ATan2(Double_t(pt),Double_t(p)));
317 if (theta > fThetaMax || theta < fThetaMin)
318 {
319// printf("\n failed theta cut %f %f %f \n",theta,fThetaMin,fThetaMax);
320 return kFALSE;
321 }
322
323 return kTRUE;
324}
325
326
327
328