Added two missing includes to allow macro compilation (thanks to Laurent for remarkin...
[u/mrichter/AliRoot.git] / ITS / AliITSVertexer3D.cxx
1 /**************************************************************************
2  * Copyright(c) 2006-2008, 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 #include <TTree.h>
16 #include "AliESDVertex.h"
17 #include "AliLog.h"
18 #include "AliStrLine.h"
19 #include "AliTracker.h"
20 #include "AliITSDetTypeRec.h"
21 #include "AliITSRecPoint.h"
22 #include "AliITSgeomTGeo.h"
23 #include "AliVertexerTracks.h"
24 #include "AliITSVertexer3D.h"
25 #include "AliITSVertexerZ.h"
26 #include "AliITSSortTrkl.h"
27 /////////////////////////////////////////////////////////////////
28 // this class implements a method to determine
29 // the 3 coordinates of the primary vertex
30 // for p-p collisions 
31 // It can be used successfully with Pb-Pb collisions
32 ////////////////////////////////////////////////////////////////
33
34 ClassImp(AliITSVertexer3D)
35
36 /* $Id$ */
37
38 //______________________________________________________________________
39 AliITSVertexer3D::AliITSVertexer3D():
40   AliITSVertexer(),
41   fLines("AliStrLine",1000),
42   fVert3D(),
43   fCoarseDiffPhiCut(0.),
44   fFineDiffPhiCut(0.),
45   fCutOnPairs(0.),
46   fCoarseMaxRCut(0.),
47   fMaxRCut(0.),
48   fZCutDiamond(0.),
49   fMaxZCut(0.),
50   fDCAcut(0.),
51   fDiffPhiMax(0.),
52   fMeanPSelTrk(0.),
53   fMeanPtSelTrk(0.),
54   fUsedCluster(kMaxCluPerMod*kNSPDMod),
55   fZHisto(0),
56   fDCAforPileup(0.),
57   fDiffPhiforPileup(0.),
58   fBinSizeR(0.),
59   fBinSizeZ(0.),
60   fPileupAlgo(0)
61 {
62   // Default constructor
63   SetCoarseDiffPhiCut();
64   SetFineDiffPhiCut();
65   SetCutOnPairs();
66   SetCoarseMaxRCut();
67   SetMaxRCut();
68   SetZCutDiamond();
69   SetMaxZCut();
70   SetDCACut();
71   SetDiffPhiMax();
72   SetMeanPSelTracks();
73   SetMeanPtSelTracks();
74   SetMinDCAforPileup();
75   SetDeltaPhiforPileup();
76   SetPileupAlgo();
77   SetBinSizeR();
78   SetBinSizeZ();
79   Double_t binsize=0.02; // default 200 micron
80   Int_t nbins=static_cast<Int_t>(1+2*fZCutDiamond/binsize);
81   fZHisto=new TH1F("hz","",nbins,-fZCutDiamond,-fZCutDiamond+binsize*nbins);
82 }
83
84 //______________________________________________________________________
85 AliITSVertexer3D::~AliITSVertexer3D() {
86   // Destructor
87   fLines.Clear("C");
88   if(fZHisto) delete fZHisto;
89 }
90
91 //______________________________________________________________________
92 void AliITSVertexer3D::ResetVert3D(){
93   //
94   ResetVertex();
95   fVert3D.SetXv(0.);
96   fVert3D.SetYv(0.);
97   fVert3D.SetZv(0.);
98   fVert3D.SetDispersion(0.);
99   fVert3D.SetNContributors(0);
100   fUsedCluster.ResetAllBits(0);
101 }
102 //______________________________________________________________________
103 AliESDVertex* AliITSVertexer3D::FindVertexForCurrentEvent(TTree *itsClusterTree){
104   // Defines the AliESDVertex for the current event
105   ResetVert3D();
106   AliDebug(1,"FindVertexForCurrentEvent - 3D - PROCESSING NEXT EVENT");
107   fLines.Clear("C");
108   fCurrentVertex = NULL;
109
110   Int_t nolines = FindTracklets(itsClusterTree,0);
111   if(nolines>=2){
112     Int_t rc=Prepare3DVertex(0);
113     if(fPileupAlgo == 2 && rc == 0) FindVertex3DIterative();
114     else if(fPileupAlgo<2 && rc == 0) FindVertex3D(itsClusterTree);
115   }
116
117   if(!fCurrentVertex){
118     AliITSVertexerZ vertz(GetNominalPos()[0],GetNominalPos()[1]);
119     vertz.SetDetTypeRec(GetDetTypeRec());
120     AliDebug(1,"Call Vertexer Z\n");
121     vertz.SetLowLimit(-fZCutDiamond);
122     vertz.SetHighLimit(fZCutDiamond);
123     AliESDVertex* vtxz = vertz.FindVertexForCurrentEvent(itsClusterTree);
124     if(vtxz){
125       Double_t position[3]={GetNominalPos()[0],GetNominalPos()[1],vtxz->GetZv()};
126       Double_t covmatrix[6];
127       vtxz->GetCovMatrix(covmatrix);
128       Double_t chi2=99999.;
129       Int_t    nContr=vtxz->GetNContributors();
130       fCurrentVertex = new AliESDVertex(position,covmatrix,chi2,nContr);    
131       fCurrentVertex->SetTitle("vertexer: Z");
132       fCurrentVertex->SetName("SPDVertexZ");
133       delete vtxz;
134     }
135
136   }
137   FindMultiplicity(itsClusterTree);
138   return fCurrentVertex;
139 }  
140
141 //______________________________________________________________________
142 void AliITSVertexer3D::FindVertex3D(TTree *itsClusterTree){
143   // 3D algorithm
144   /*  uncomment to debug
145       printf("Vertex found in first iteration:\n");
146       fVert3D.Print();
147       printf("Start second iteration\n");
148       end of debug lines  */
149   if(fVert3D.GetNContributors()>0){
150     fLines.Clear("C");
151     Int_t nolines = FindTracklets(itsClusterTree,1);
152     if(nolines>=2){
153       Int_t rc=Prepare3DVertex(1);
154       if(rc!=0) fVert3D.SetNContributors(0); // exclude this vertex
155     }
156   }
157   /*  uncomment to debug 
158       printf("Vertex found in second iteration:\n");
159       fVert3D.Print();
160       end of debug lines  */ 
161   
162   Double_t vRadius=TMath::Sqrt(fVert3D.GetXv()*fVert3D.GetXv()+fVert3D.GetYv()*fVert3D.GetYv());
163   if(vRadius<GetPipeRadius() && fVert3D.GetNContributors()>0){
164     Double_t position[3]={fVert3D.GetXv(),fVert3D.GetYv(),fVert3D.GetZv()};
165     Double_t covmatrix[6];
166     fVert3D.GetCovMatrix(covmatrix);
167     Double_t chi2=99999.;
168     Int_t    nContr=fVert3D.GetNContributors();
169     fCurrentVertex = new AliESDVertex(position,covmatrix,chi2,nContr);    
170     fCurrentVertex->SetTitle("vertexer: 3D");
171     fCurrentVertex->SetName("SPDVertex3D");
172     fCurrentVertex->SetDispersion(fVert3D.GetDispersion());
173     fNoVertices=1;
174     
175     switch(fPileupAlgo){
176     case 0: PileupFromZ(); break;
177     case 1: FindOther3DVertices(itsClusterTree); break;
178     default: AliError("Wrong pileup algorithm"); break;
179     }
180     if(fNoVertices==1){
181       fVertArray = new AliESDVertex[1];
182       fVertArray[0]=(*fCurrentVertex);    
183     }
184   }
185 }
186
187 //______________________________________________________________________
188 void AliITSVertexer3D::FindVertex3DIterative(){
189   // Defines the AliESDVertex for the current event
190   Int_t numsor=fLines.GetEntriesFast()*(fLines.GetEntriesFast()-1)/2;
191   //cout<<"AliITSVertexer3D::FindVertexForCurentEvent: Number of tracklets selected for vertexing "<<fLines.GetEntriesFast()<<"; Number of pairs: "<<numsor<<endl;
192   AliITSSortTrkl srt(fLines,numsor,fCutOnPairs,fCoarseMaxRCut); 
193   srt.FindClusters();   
194   AliInfo(Form("Number of vertices: %d",srt.GetNumberOfClusters()));
195       
196   fNoVertices = srt.GetNumberOfClusters();
197   //printf("fNoVertices = %d \n",fNoVertices);
198   if(fNoVertices>0){
199     fVertArray = new AliESDVertex[fNoVertices];
200     for(Int_t kk=0; kk<srt.GetNumberOfClusters(); kk++){
201       Int_t size = 0;
202       Int_t *labels = srt.GetTrackletsLab(kk,size);
203       /*
204         Int_t *pairs = srt.GetClusters(kk);
205         Int_t nopai = srt.GetSizeOfCluster(kk);
206         cout<<"***** Vertex number "<<kk<<".  Pairs: \n";
207         for(Int_t jj=0;jj<nopai;jj++){
208         cout<<pairs[jj]<<" - ";
209         if(jj>0 & jj%8==0)cout<<endl;
210         }
211         cout<<endl;
212         cout<<"***** Vertex number "<<kk<<".  Labels: \n";
213       */
214       AliStrLine **tclo = new AliStrLine* [size];
215       for(Int_t jj=0;jj<size;jj++){
216         //          cout<<labels[jj]<<" - ";
217         //          if(jj>0 & jj%8==0)cout<<endl;
218         tclo[jj] = dynamic_cast<AliStrLine*>(fLines[labels[jj]]);
219       }
220       //          cout<<endl;
221       delete []labels;
222       fVertArray[kk]=AliVertexerTracks::TrackletVertexFinder(tclo,size);
223       delete [] tclo;
224       //          fVertArray[kk].PrintStatus();
225       if(kk == 1){
226         // at least one second vertex is present
227         fIsPileup = kTRUE;
228         fNTrpuv = fVertArray[kk].GetNContributors();
229         fZpuv = fVertArray[kk].GetZv();
230       }
231     }
232     Double_t vRadius=TMath::Sqrt(fVertArray[0].GetXv()*fVertArray[0].GetXv()+fVertArray[0].GetYv()*fVertArray[0].GetYv());
233     if(vRadius<GetPipeRadius() && fVertArray[0].GetNContributors()>0){
234       Double_t position[3]={fVertArray[0].GetXv(),fVertArray[0].GetYv(),fVertArray[0].GetZv()};
235       Double_t covmatrix[6];
236       fVertArray[0].GetCovMatrix(covmatrix);
237       Double_t chi2=99999.;
238       Int_t    nContr=fVertArray[0].GetNContributors();
239       fCurrentVertex = new AliESDVertex(position,covmatrix,chi2,nContr);    
240       fCurrentVertex->SetTitle("vertexer: 3D");
241       fCurrentVertex->SetName("SPDVertex3D");
242       fCurrentVertex->SetDispersion(fVertArray[0].GetDispersion());  
243     }
244   }
245
246 }  
247
248 //______________________________________________________________________
249 Bool_t AliITSVertexer3D::DistBetweenVertices(AliESDVertex &a, AliESDVertex &b, Double_t test, Double_t &dist){
250   // method to compare the distance between vertices a and b with "test"
251   //it returns kTRUE is the distance is less or equal to test
252   dist = (a.GetX()-b.GetX()) * (a.GetX()-b.GetX());
253   dist +=  (a.GetY()-b.GetY()) * (a.GetY()-b.GetY());
254   dist +=  (a.GetZ()-b.GetZ()) * (a.GetZ()-b.GetZ());
255   dist = TMath::Sqrt(dist);
256   if(dist <= test)return kTRUE;
257   return kFALSE;
258 }
259
260
261 //______________________________________________________________________
262 Int_t AliITSVertexer3D::FindTracklets(TTree *itsClusterTree, Int_t optCuts){
263   // All the possible combinations between recpoints on layer 1and 2 are
264   // considered. Straight lines (=tracklets)are formed. 
265   // The tracklets are processed in Prepare3DVertex
266
267   if(!GetDetTypeRec())AliFatal("DetTypeRec pointer has not been set");
268
269   TTree *tR = itsClusterTree;
270   fDetTypeRec->ResetRecPoints();
271   fDetTypeRec->SetTreeAddressR(tR);
272   TClonesArray *itsRec  = 0;
273   if(optCuts==0) fZHisto->Reset();
274  // gc1 are local and global coordinates for layer 1
275   Float_t gc1f[3]={0.,0.,0.};
276   Double_t gc1[3]={0.,0.,0.};
277   // gc2 are local and global coordinates for layer 2
278   Float_t gc2f[3]={0.,0.,0.};
279   Double_t gc2[3]={0.,0.,0.};
280
281   itsRec = fDetTypeRec->RecPoints();
282   TBranch *branch = NULL;
283   branch = tR->GetBranch("ITSRecPoints");
284   if(!branch){
285     AliWarning("Null pointer for RecPoints branch, vertex not calculated");
286     return -1;
287   }
288
289   // Set values for cuts
290   Double_t xbeam=GetNominalPos()[0]; 
291   Double_t ybeam=GetNominalPos()[1];
292   Double_t zvert=0.;
293   Double_t deltaPhi=fCoarseDiffPhiCut;
294   Double_t deltaR=fCoarseMaxRCut;
295   Double_t dZmax=fZCutDiamond;
296   if(fPileupAlgo == 2){
297     deltaPhi=fFineDiffPhiCut;
298     deltaR=fMaxRCut;
299     if(optCuts != 0)AliWarning(Form("fPileupAlgo=2 AND optCuts=%d has been selected. It should be 0",optCuts));
300   } else if(optCuts==1){
301     xbeam=fVert3D.GetXv();
302     ybeam=fVert3D.GetYv();
303     zvert=fVert3D.GetZv();
304     deltaPhi = fDiffPhiMax; 
305     deltaR=fMaxRCut;
306     dZmax=fMaxZCut;
307   } else if(optCuts==2){
308     xbeam=fVert3D.GetXv();
309     ybeam=fVert3D.GetYv();
310     deltaPhi = fDiffPhiforPileup;
311     deltaR=fMaxRCut;
312   }
313
314   Int_t nrpL1 = 0;    // number of rec points on layer 1
315   Int_t nrpL2 = 0;    // number of rec points on layer 2
316
317   // By default irstL1=0 and lastL1=79
318   Int_t firstL1 = AliITSgeomTGeo::GetModuleIndex(1,1,1);
319   Int_t lastL1 = AliITSgeomTGeo::GetModuleIndex(2,1,1)-1;
320   for(Int_t module= firstL1; module<=lastL1;module++){  // count number of recopints on layer 1
321     branch->GetEvent(module);
322     nrpL1+= itsRec->GetEntries();
323     fDetTypeRec->ResetRecPoints();
324   }
325   //By default firstL2=80 and lastL2=239
326   Int_t firstL2 = AliITSgeomTGeo::GetModuleIndex(2,1,1);
327   Int_t lastL2 = AliITSgeomTGeo::GetModuleIndex(3,1,1)-1;
328   for(Int_t module= firstL2; module<=lastL2;module++){  // count number of recopints on layer 2
329     branch->GetEvent(module);
330     nrpL2+= itsRec->GetEntries();
331     fDetTypeRec->ResetRecPoints();
332   }
333   if(nrpL1 == 0 || nrpL2 == 0){
334     AliDebug(1,Form("No RecPoints in at least one SPD layer (%d %d)",nrpL1,nrpL2));
335     return -1;
336   }
337   AliDebug(1,Form("RecPoints on Layer 1,2 = %d, %d\n",nrpL1,nrpL2));
338
339   Double_t a[3]={xbeam,ybeam,0.}; 
340   Double_t b[3]={xbeam,ybeam,10.};
341   AliStrLine zeta(a,b,kTRUE);
342   static Double_t bField=TMath::Abs(AliTracker::GetBz()/10.); //T
343   SetMeanPPtSelTracks(bField);
344   
345   Int_t nolines = 0;
346   // Loop on modules of layer 1
347   for(Int_t modul1= firstL1; modul1<=lastL1;modul1++){   // Loop on modules of layer 1
348     if(!fUseModule[modul1]) continue;
349     UShort_t ladder=int(modul1/4)+1; // ladders are numbered starting from 1
350     branch->GetEvent(modul1);
351     Int_t nrecp1 = itsRec->GetEntries();
352     static TClonesArray prpl1("AliITSRecPoint",nrecp1);
353     prpl1.SetOwner();
354     for(Int_t j=0;j<nrecp1;j++){
355       AliITSRecPoint *recp = (AliITSRecPoint*)itsRec->At(j);
356       new(prpl1[j])AliITSRecPoint(*recp);
357     }
358     fDetTypeRec->ResetRecPoints();
359     for(Int_t j=0;j<nrecp1;j++){
360       if(j>kMaxCluPerMod) continue;
361       UShort_t idClu1=modul1*kMaxCluPerMod+j;
362       if(fUsedCluster.TestBitNumber(idClu1)) continue;
363       AliITSRecPoint *recp1 = (AliITSRecPoint*)prpl1.At(j);
364       recp1->GetGlobalXYZ(gc1f);
365       for(Int_t ico=0;ico<3;ico++)gc1[ico]=gc1f[ico];
366
367       Double_t phi1 = TMath::ATan2(gc1[1]-ybeam,gc1[0]-xbeam);
368       if(phi1<0)phi1=2*TMath::Pi()+phi1;
369       for(Int_t ladl2=0 ; ladl2<fLadOnLay2*2+1;ladl2++){
370         for(Int_t k=0;k<4;k++){
371           Int_t ladmod=fLadders[ladder-1]+ladl2;
372           if(ladmod>AliITSgeomTGeo::GetNLadders(2)) ladmod=ladmod-AliITSgeomTGeo::GetNLadders(2);
373           Int_t modul2=AliITSgeomTGeo::GetModuleIndex(2,ladmod,k+1);
374           if(!fUseModule[modul2]) continue;
375           branch->GetEvent(modul2);
376           Int_t nrecp2 = itsRec->GetEntries();
377           for(Int_t j2=0;j2<nrecp2;j2++){
378             if(j2>kMaxCluPerMod) continue;
379             UShort_t idClu2=modul2*kMaxCluPerMod+j2;
380             if(fUsedCluster.TestBitNumber(idClu2)) continue;
381             AliITSRecPoint *recp2 = (AliITSRecPoint*)itsRec->At(j2);
382             recp2->GetGlobalXYZ(gc2f);
383             for(Int_t ico=0;ico<3;ico++)gc2[ico]=gc2f[ico];
384             Double_t phi2 = TMath::ATan2(gc2[1]-ybeam,gc2[0]-xbeam);
385             if(phi2<0)phi2=2*TMath::Pi()+phi2;
386             Double_t diff = TMath::Abs(phi2-phi1); 
387             if(diff>TMath::Pi())diff=2.*TMath::Pi()-diff; 
388             if(optCuts==0 && diff<fDiffPhiMax){
389               Double_t r1=TMath::Sqrt(gc1[0]*gc1[0]+gc1[1]*gc1[1]);
390               Double_t zc1=gc1[2];
391               Double_t r2=TMath::Sqrt(gc2[0]*gc2[0]+gc2[1]*gc2[1]);
392               Double_t zc2=gc2[2];
393               Double_t zr0=(r2*zc1-r1*zc2)/(r2-r1); //Z @ null radius
394               fZHisto->Fill(zr0);
395             }
396             if(diff>deltaPhi)continue;
397             AliStrLine line(gc1,gc2,kTRUE);
398             Double_t cp[3];
399             Int_t retcode = line.Cross(&zeta,cp);
400             if(retcode<0)continue;
401             Double_t dca = line.GetDCA(&zeta);
402             if(dca<0.) continue;
403             if(dca>deltaR)continue;
404             Double_t deltaZ=cp[2]-zvert;
405             if(TMath::Abs(deltaZ)>dZmax)continue;
406
407             if(nolines == 0){
408               if(fLines.GetEntriesFast()>0)fLines.Clear("C");
409             }
410             Float_t cov[6];
411             recp2->GetGlobalCov(cov);
412
413
414             Double_t rad1=TMath::Sqrt(gc1[0]*gc1[0]+gc1[1]*gc1[1]);
415             Double_t rad2=TMath::Sqrt(gc2[0]*gc2[0]+gc2[1]*gc2[1]);
416             Double_t factor=(rad1+rad2)/(rad2-rad1); //factor to account for error on tracklet direction 
417
418             Double_t curvErr=0;
419             if(bField>0.00001){
420               Double_t curvRadius=fMeanPtSelTrk/(0.3*bField)*100; //cm 
421               Double_t dRad=TMath::Sqrt((gc1[0]-gc2[0])*(gc1[0]-gc2[0])+(gc1[1]-gc2[1])*(gc1[1]-gc2[1]));
422               Double_t aux=dRad/2.+rad1;
423               curvErr=TMath::Sqrt(curvRadius*curvRadius-dRad*dRad/4.)-TMath::Sqrt(curvRadius*curvRadius-aux*aux); //cm
424             }
425             Double_t sigmasq[3];
426             sigmasq[0]=(cov[0]+curvErr*curvErr/2.)*factor*factor;
427             sigmasq[1]=(cov[3]+curvErr*curvErr/2.)*factor*factor;
428             sigmasq[2]=cov[5]*factor*factor;
429
430             // Multiple scattering
431             Double_t pOverMass=fMeanPSelTrk/0.140;
432             Double_t beta2=pOverMass*pOverMass/(1+pOverMass*pOverMass);
433             Double_t p2=fMeanPSelTrk*fMeanPSelTrk;
434             Double_t rBP=GetPipeRadius();
435             Double_t dBP=0.08/35.3; // 800 um of Be
436             Double_t dL1=0.01; //approx. 1% of radiation length  
437             Double_t theta2BP=14.1*14.1/(beta2*p2*1e6)*dBP;
438             Double_t theta2L1=14.1*14.1/(beta2*p2*1e6)*dL1;
439             Double_t rtantheta1=(rad2-rad1)*TMath::Tan(TMath::Sqrt(theta2L1));
440             Double_t rtanthetaBP=(rad1-rBP)*TMath::Tan(TMath::Sqrt(theta2BP));
441             for(Int_t ico=0; ico<3;ico++){    
442               sigmasq[ico]+=rtantheta1*rtantheta1*factor*factor/3.;
443               sigmasq[ico]+=rtanthetaBP*rtanthetaBP*factor*factor/3.;
444             }
445             Double_t wmat[9]={1.,0.,0.,0.,1.,0.,0.,0.,1.};
446             if(sigmasq[0]!=0.) wmat[0]=1./sigmasq[0];
447             if(sigmasq[1]!=0.) wmat[4]=1./sigmasq[1];
448             if(sigmasq[2]!=0.) wmat[8]=1./sigmasq[2];
449             new(fLines[nolines++])AliStrLine(gc1,sigmasq,wmat,gc2,kTRUE,idClu1,idClu2);
450
451           }
452           fDetTypeRec->ResetRecPoints();
453         }
454       }
455     }
456     prpl1.Clear();
457   }
458   if(nolines == 0)return -2;
459   return nolines;
460 }
461
462 //______________________________________________________________________
463 Int_t  AliITSVertexer3D::Prepare3DVertex(Int_t optCuts){
464   // Finds the 3D vertex information using tracklets
465   Int_t retcode = -1;
466
467   Double_t xbeam=GetNominalPos()[0];
468   Double_t ybeam=GetNominalPos()[1];
469   Double_t zvert=0.;
470   Double_t deltaR=fCoarseMaxRCut;
471   if(fPileupAlgo == 2) {
472     deltaR=fMaxRCut;
473     if(optCuts!=0)AliWarning(Form("fPileupAlgo=2 AND optCuts=%d. It should be 0",optCuts));
474   }
475   Double_t dZmax=fZCutDiamond;
476   if(optCuts==1){
477     xbeam=fVert3D.GetXv();
478     ybeam=fVert3D.GetYv();
479     zvert=fVert3D.GetZv();
480     deltaR=fMaxRCut;
481     dZmax=fMaxZCut;
482   }else if(optCuts==2){
483     xbeam=fVert3D.GetXv();
484     ybeam=fVert3D.GetYv();
485     deltaR=fMaxRCut;
486   }
487
488   Double_t rl=-fCoarseMaxRCut;
489   Double_t rh=fCoarseMaxRCut;
490   Double_t zl=-fZCutDiamond;
491   Double_t zh=fZCutDiamond;
492   Int_t nbr=(Int_t)((rh-rl)/fBinSizeR+0.0001);
493   Int_t nbz=(Int_t)((zh-zl)/fBinSizeZ+0.0001);
494   Int_t nbrcs=(Int_t)((rh-rl)/(fBinSizeR*2.)+0.0001);
495   Int_t nbzcs=(Int_t)((zh-zl)/(fBinSizeZ*2.)+0.0001);
496
497   TH3F *h3d = NULL;
498   TH3F *h3dcs = NULL;
499   if(fPileupAlgo !=2){
500     h3d = new TH3F("h3d","xyz distribution",nbr,rl,rh,nbr,rl,rh,nbz,zl,zh);
501     h3dcs = new TH3F("h3dcs","xyz distribution",nbrcs,rl,rh,nbrcs,rl,rh,nbzcs,zl,zh);
502   }
503   // cleanup of the TCLonesArray of tracklets (i.e. fakes are removed)
504   Int_t *validate = new Int_t [fLines.GetEntriesFast()];
505   for(Int_t i=0; i<fLines.GetEntriesFast();i++)validate[i]=0;
506   for(Int_t i=0; i<fLines.GetEntriesFast()-1;i++){
507     AliStrLine *l1 = (AliStrLine*)fLines.At(i);
508     for(Int_t j=i+1;j<fLines.GetEntriesFast();j++){
509       AliStrLine *l2 = (AliStrLine*)fLines.At(j);
510       Double_t dca=l1->GetDCA(l2);
511       if(dca > fDCAcut || dca<0.00001) continue;
512       Double_t point[3];
513       Int_t retc = l1->Cross(l2,point);
514       if(retc<0)continue;
515       Double_t deltaZ=point[2]-zvert;
516      if(TMath::Abs(deltaZ)>dZmax)continue;
517       Double_t rad=TMath::Sqrt(point[0]*point[0]+point[1]*point[1]);
518       if(rad>fCoarseMaxRCut)continue;
519       Double_t deltaX=point[0]-xbeam;
520       Double_t deltaY=point[1]-ybeam;
521       Double_t raddist=TMath::Sqrt(deltaX*deltaX+deltaY*deltaY);
522       if(raddist>deltaR)continue;
523       validate[i]=1;
524       validate[j]=1;
525       if(fPileupAlgo != 2){
526         h3d->Fill(point[0],point[1],point[2]);
527         h3dcs->Fill(point[0],point[1],point[2]);
528       }
529     }
530   }
531
532
533
534   Int_t numbtracklets=0;
535   for(Int_t i=0; i<fLines.GetEntriesFast();i++)if(validate[i]>=1)numbtracklets++;
536   if(numbtracklets<2){
537     delete [] validate; 
538     if(fPileupAlgo != 2){
539       delete h3d; 
540       delete h3dcs; 
541     }
542     return retcode; 
543   }
544
545   for(Int_t i=0; i<fLines.GetEntriesFast();i++){
546     if(validate[i]<1)fLines.RemoveAt(i);
547   }
548   fLines.Compress();
549   AliDebug(1,Form("Number of tracklets (after compress)%d ",fLines.GetEntriesFast()));
550   delete [] validate;
551
552   // Exit here if Pileup Algorithm 2 has been chosen
553   if(fPileupAlgo == 2)return 0;
554   //         
555
556
557   //        Find peaks in histos
558
559   Double_t peak[3]={0.,0.,0.};
560   Int_t ntrkl,ntimes;
561   FindPeaks(h3d,peak,ntrkl,ntimes);  
562   delete h3d;
563   Double_t binsizer=(rh-rl)/nbr;
564   Double_t binsizez=(zh-zl)/nbz;
565   if(optCuts==0 && (ntrkl<=2 || ntimes>1)){
566     ntrkl=0;
567     ntimes=0;
568     FindPeaks(h3dcs,peak,ntrkl,ntimes);  
569     binsizer=(rh-rl)/nbrcs;
570     binsizez=(zh-zl)/nbzcs;
571     if(ntrkl==1 || ntimes>1){delete h3dcs; return retcode;}
572   }
573   delete h3dcs;
574
575   //         Second selection loop
576
577   Double_t bs=(binsizer+binsizez)/2.;
578   for(Int_t i=0; i<fLines.GetEntriesFast();i++){
579     AliStrLine *l1 = (AliStrLine*)fLines.At(i);
580     if(l1->GetDistFromPoint(peak)>2.5*bs)fLines.RemoveAt(i);
581   }
582   fLines.Compress();
583   AliDebug(1,Form("Number of tracklets (after 2nd compression) %d",fLines.GetEntriesFast()));
584
585   if(fLines.GetEntriesFast()>1){
586     retcode=0;
587     //  find a first candidate for the primary vertex
588     fVert3D=AliVertexerTracks::TrackletVertexFinder(&fLines,0); 
589     // make a further selection on tracklets based on this first candidate
590     fVert3D.GetXYZ(peak);
591     AliDebug(1,Form("FIRST V candidate: %f ; %f ; %f",peak[0],peak[1],peak[2]));
592     for(Int_t i=0; i<fLines.GetEntriesFast();i++){
593       AliStrLine *l1 = (AliStrLine*)fLines.At(i);
594       if(l1->GetDistFromPoint(peak)> fDCAcut)fLines.RemoveAt(i);
595     }
596     fLines.Compress();
597     AliDebug(1,Form("Number of tracklets (after 3rd compression) %d",fLines.GetEntriesFast()));
598     if(fLines.GetEntriesFast()>1){// this new tracklet selection is used
599       fVert3D=AliVertexerTracks::TrackletVertexFinder(&fLines,0);
600     }
601   }
602   return retcode;  
603 }
604
605 //________________________________________________________
606 void AliITSVertexer3D::SetMeanPPtSelTracks(Double_t fieldTesla){
607   // Sets mean values of Pt based on the field
608   // for P (used in multiple scattering) the most probable value is used
609   if(TMath::Abs(fieldTesla-0.5)<0.01){
610     SetMeanPSelTracks(0.375);
611     SetMeanPtSelTracks(0.630);
612   }else if(TMath::Abs(fieldTesla-0.4)<0.01){
613     SetMeanPSelTracks(0.375);
614     SetMeanPtSelTracks(0.580);
615   }else if(TMath::Abs(fieldTesla-0.2)<0.01){
616     SetMeanPSelTracks(0.375);
617     SetMeanPtSelTracks(0.530);
618   }else if(fieldTesla<0.00001){
619     SetMeanPSelTracks(0.375);
620     SetMeanPtSelTracks(0.230);
621   }else{
622     SetMeanPSelTracks();
623     SetMeanPtSelTracks();
624   }
625 }
626
627 //________________________________________________________
628 void AliITSVertexer3D::FindPeaks(TH3F* histo, Double_t *peak, Int_t &nOfTracklets, Int_t &nOfTimes){
629   // Finds bin with max contents in 3D histo of tracket intersections
630   TAxis *xax = histo->GetXaxis();  
631   TAxis *yax = histo->GetYaxis();
632   TAxis *zax = histo->GetZaxis();
633   peak[0]=0.;
634   peak[1]=0.;
635   peak[2]=0.;
636   nOfTracklets = 0;
637   nOfTimes=0;
638   Int_t peakbin[3]={0,0,0};
639   Int_t peak2bin[3]={-1,-1,-1};
640   Int_t bc2=-1;
641   for(Int_t i=xax->GetFirst();i<=xax->GetLast();i++){
642     Double_t xval = xax->GetBinCenter(i);
643     for(Int_t j=yax->GetFirst();j<=yax->GetLast();j++){
644       Double_t yval = yax->GetBinCenter(j);
645       for(Int_t k=zax->GetFirst();k<=zax->GetLast();k++){
646         Double_t zval = zax->GetBinCenter(k);
647         Int_t bc =(Int_t)histo->GetBinContent(i,j,k);
648         if(bc==0) continue;
649         if(bc>nOfTracklets){
650           nOfTracklets=bc;
651           peak[2] = zval;
652           peak[1] = yval;
653           peak[0] = xval;
654           peakbin[2] = k;
655           peakbin[1] = j;
656           peakbin[0] = i;
657           peak2bin[2] = -1;
658           peak2bin[1] = -1;
659           peak2bin[0] = -1;
660           bc2=-1;
661           nOfTimes = 1;
662         }else if(bc==nOfTracklets){
663           if(TMath::Abs(i-peakbin[0])<=1 && TMath::Abs(j-peakbin[1])<=1 && TMath::Abs(k-peakbin[2])<=1){
664             peak2bin[2] = k;
665             peak2bin[1] = j;
666             peak2bin[0] = i;
667             bc2=bc;
668             nOfTimes = 1;
669           }else{
670             nOfTimes++;
671           }
672         }
673       }
674     }
675   }
676   if(peak2bin[0]>=-1 && bc2!=-1){ // two contiguous peak-cells with same contents
677     peak[0]=0.5*(xax->GetBinCenter(peakbin[0])+xax->GetBinCenter(peak2bin[0]));
678     peak[1]=0.5*(yax->GetBinCenter(peakbin[1])+yax->GetBinCenter(peak2bin[1]));
679     peak[2]=0.5*(zax->GetBinCenter(peakbin[2])+zax->GetBinCenter(peak2bin[2]));
680     nOfTracklets+=bc2;
681     nOfTimes=1;
682   }
683 }
684 //________________________________________________________
685 void AliITSVertexer3D::MarkUsedClusters(){
686   // Mark clusters of tracklets used in vertex claulation
687   for(Int_t i=0; i<fLines.GetEntriesFast();i++){
688     AliStrLine *lin = (AliStrLine*)fLines.At(i);
689     Int_t idClu1=lin->GetIdPoint(0);
690     Int_t idClu2=lin->GetIdPoint(1);
691     fUsedCluster.SetBitNumber(idClu1);
692     fUsedCluster.SetBitNumber(idClu2);
693   }
694 }
695 //________________________________________________________
696 Int_t AliITSVertexer3D::RemoveTracklets(){
697   // Remove trackelts close to first found vertex
698   Double_t vert[3]={fVert3D.GetXv(),fVert3D.GetYv(),fVert3D.GetZv()};
699   Int_t nRemoved=0;
700   for(Int_t i=0; i<fLines.GetEntriesFast();i++){
701     AliStrLine *lin = (AliStrLine*)fLines.At(i);
702     if(lin->GetDistFromPoint(vert)<fDCAforPileup){
703       Int_t idClu1=lin->GetIdPoint(0);
704       Int_t idClu2=lin->GetIdPoint(1);
705       fUsedCluster.SetBitNumber(idClu1);
706       fUsedCluster.SetBitNumber(idClu2);
707       fLines.RemoveAt(i);
708       ++nRemoved;
709     }
710   }
711   fLines.Compress();
712   return nRemoved;
713 }
714 //________________________________________________________
715 void AliITSVertexer3D::FindOther3DVertices(TTree *itsClusterTree){
716   // pileup identification based on 3D vertexing with not used clusters
717   MarkUsedClusters();
718   fLines.Clear("C");
719   Int_t nolines = FindTracklets(itsClusterTree,2);
720   if(nolines>=2){
721     Int_t nr=RemoveTracklets();
722     nolines-=nr;
723     if(nolines>=2){
724       Int_t rc=Prepare3DVertex(2);
725       if(rc==0){ 
726         fVert3D=AliVertexerTracks::TrackletVertexFinder(&fLines,0);
727         if(fVert3D.GetNContributors()>=fMinTrackletsForPilup){
728           fIsPileup=kTRUE;
729           fNoVertices=2;
730           fVertArray = new AliESDVertex[2];
731           fVertArray[0]=(*fCurrentVertex);
732           fVertArray[1]=fVert3D;
733           fZpuv=fVert3D.GetZv();
734           fNTrpuv=fVert3D.GetNContributors();
735         }
736       }
737     }
738   }
739 }
740 //______________________________________________________________________
741 void AliITSVertexer3D::PileupFromZ(){
742   // Calls the pileup algorithm of ALiITSVertexerZ
743   Int_t binmin, binmax;
744   Int_t nPeaks=AliITSVertexerZ::GetPeakRegion(fZHisto,binmin,binmax);   
745   if(nPeaks==2)AliWarning("2 peaks found");
746   Int_t firstPeakCont=0;
747   Double_t firstPeakPos=0.;
748   for(Int_t i=binmin-1;i<=binmax+1;i++){
749     firstPeakCont+=static_cast<Int_t>(fZHisto->GetBinContent(i));
750     firstPeakPos+=fZHisto->GetBinContent(i)*fZHisto->GetBinCenter(i);
751   }
752   if(firstPeakCont>0){ 
753     firstPeakPos/=firstPeakCont;
754     Int_t ncontr2=0;
755     if(firstPeakCont>fMinTrackletsForPilup){     
756       Float_t secPeakPos;
757       ncontr2=AliITSVertexerZ::FindSecondPeak(fZHisto,binmin,binmax,secPeakPos);
758       if(ncontr2>=fMinTrackletsForPilup){ 
759         fIsPileup=kTRUE;
760         fNoVertices=2;
761         AliESDVertex secondVert(secPeakPos,0.1,ncontr2);
762         fVertArray = new AliESDVertex[2];
763         fVertArray[0]=(*fCurrentVertex);
764         fVertArray[1]=secondVert;
765         fZpuv=secPeakPos;
766         fNTrpuv=ncontr2;
767       }
768     }
769   }
770 }
771 //________________________________________________________
772 void AliITSVertexer3D::PrintStatus() const {
773   // Print current status
774   printf("=======================================================\n");
775   printf("Loose cut on Delta Phi %f\n",fCoarseDiffPhiCut);
776   printf("Cut on tracklet DCA to Z axis %f\n",fCoarseMaxRCut);
777   printf("Cut on tracklet DCA to beam axis %f\n",fMaxRCut);
778   printf("Cut on diamond (Z) %f\n",fZCutDiamond);
779   printf("Cut on DCA - tracklet to tracklet and to vertex %f\n",fDCAcut);
780   printf("Max Phi difference: %f\n",fDiffPhiMax);
781   printf("Pileup algo: %d\n",fPileupAlgo);
782   printf("Min DCA to 1st vetrtex for pileup: %f\n",fDCAforPileup);
783   printf("=======================================================\n");
784 }