/************************************************************************** * Copyright(c) 1998-2003, ALICE Experiment at CERN, All rights reserved. * * * * Author: The ALICE Off-line Project. * * Contributors are mentioned in the code where appropriate. * * * * Permission to use, copy, modify and distribute this software and its * * documentation strictly for non-commercial purposes is hereby granted * * without fee, provided that the above copyright notice appears in all * * copies and that both the copyright notice and this permission notice * * appear in the supporting documentation. The authors make no claims * * about the suitability of this software for any purpose. It is * * provided "as is" without express or implied warranty. * **************************************************************************/ //----------------------------------------------------------------- // Implementation of the vertexer from ESD tracks // // Origin: AliITSVertexerTracks // A.Dainese, Padova, // andrea.dainese@pd.infn.it // M.Masera, Torino, // massimo.masera@to.infn.it // Moved to STEER and adapted to ESD tracks: // F.Prino, Torino, prino@to.infn.it //----------------------------------------------------------------- //---- Root headers -------- #include #include #include #include #include //---- AliRoot headers ----- #include "AliStrLine.h" #include "AliVertexerTracks.h" #include "AliESDEvent.h" #include "AliESDtrack.h" ClassImp(AliVertexerTracks) //---------------------------------------------------------------------------- AliVertexerTracks::AliVertexerTracks(): TObject(), fVert(), fCurrentVertex(0), fFieldkG(-999.), fConstraint(kFALSE), fOnlyFitter(kFALSE), fMinTracks(1), fMinITSClusters(5), fTrkArray(), fTrksToSkip(0), fNTrksToSkip(0), fDCAcut(0), fAlgo(1), fNSigma(3), fMaxd0z0(0.5), fITSin(kTRUE), fITSrefit(kTRUE), fnSigmaForUi00(1.5), fDebug(0) { // // Default constructor // SetVtxStart(); SetVtxStartSigma(); SetMinTracks(); SetMinITSClusters(); SetNSigmad0(); SetMaxd0z0(); } //---------------------------------------------------------------------------- AliVertexerTracks::AliVertexerTracks(Double_t fieldkG): TObject(), fVert(), fCurrentVertex(0), fFieldkG(-999.), fConstraint(kFALSE), fOnlyFitter(kFALSE), fMinTracks(1), fMinITSClusters(5), fTrkArray(), fTrksToSkip(0), fNTrksToSkip(0), fDCAcut(0), fAlgo(1), fNSigma(3), fMaxd0z0(0.5), fITSin(kTRUE), fITSrefit(kTRUE), fnSigmaForUi00(1.5), fDebug(0) { // // Standard constructor // SetVtxStart(); SetVtxStartSigma(); SetMinTracks(); SetMinITSClusters(); SetNSigmad0(); SetMaxd0z0(); SetFieldkG(fieldkG); } //----------------------------------------------------------------------------- AliVertexerTracks::~AliVertexerTracks() { // Default Destructor // The objects pointed by the following pointer are not owned // by this class and are not deleted fCurrentVertex = 0; if(fTrksToSkip) { delete [] fTrksToSkip; fTrksToSkip=NULL; } } //---------------------------------------------------------------------------- AliESDVertex* AliVertexerTracks::FindPrimaryVertex(const AliESDEvent *esdEvent) { // // Primary vertex for current ESD event // (Two iterations: // 1st with 5*fNSigma*sigma cut w.r.t. to initial vertex // + cut on sqrt(d0d0+z0z0) if fConstraint=kFALSE // 2nd with fNSigma*sigma cut w.r.t. to vertex found in 1st iteration) // All ESD tracks with inside the beam pipe are then propagated to found vertex // fCurrentVertex = 0; // accept 1-track case only if constraint is available if(!fConstraint && fMinTracks==1) fMinTracks=2; // read tracks from ESD Int_t nTrksTot = (Int_t)esdEvent->GetNumberOfTracks(); if(nTrksTot<=0) { if(fDebug) printf("TooFewTracks\n"); TooFewTracks(esdEvent); return fCurrentVertex; } TDirectory * olddir = gDirectory; TFile f("VertexerTracks.root","recreate"); TTree *trkTree = new TTree("TreeT","tracks"); AliESDtrack *esdTrack = 0; trkTree->Branch("tracks","AliESDtrack",&esdTrack); Bool_t skipThis; for(Int_t i=0; iGetTrack(i); // check tracks to skip skipThis = kFALSE; for(Int_t j=0; jGetID()==fTrksToSkip[j]) { if(fDebug) printf("skipping track: %d\n",i); skipThis = kTRUE; } } if(skipThis) continue; if(fITSin) { if(!(et->GetStatus()&AliESDtrack::kITSin)) continue; if(fITSrefit && !(et->GetStatus()&AliESDtrack::kITSrefit)) continue; Int_t nclus=et->GetNcls(0); // check number of clusters in ITS if(nclusFill(); delete esdTrack; } // If fConstraint=kFALSE // run VertexFinder(1) to get rough estimate of initVertex (x,y) if(!fConstraint) { // fill fTrkArray, for VertexFinder() if(!fTrkArray.IsEmpty()) fTrkArray.Delete(); PrepareTracks(*trkTree,0); Double_t cutsave = fDCAcut; fDCAcut = 0.1; // 1 mm VertexFinder(1); // using weights, cutting dca < fDCAcut fDCAcut = cutsave; fTrkArray.Delete(); if(fVert.GetNContributors()>0) { fVert.GetXYZ(fNominalPos); fNominalPos[0] = fVert.GetXv(); fNominalPos[1] = fVert.GetYv(); fNominalPos[2] = fVert.GetZv(); if(fDebug) printf("No mean vertex: VertexFinder gives (%f, %f, %f)\n",fNominalPos[0],fNominalPos[1],fNominalPos[2]); } else { fNominalPos[0] = 0.; fNominalPos[1] = 0.; fNominalPos[2] = 0.; if(fDebug) printf("No mean vertex and VertexFinder failed\n"); } } // TWO ITERATIONS: // // ITERATION 1 // propagate tracks to fNominalPos vertex // preselect them: // if(constraint) reject for |d0|>5*fNSigma*sigma w.r.t. fNominal... vertex // else reject for |d0|\oplus|z0| > 5 mm w.r.t. fNominal... vertex // ITERATION 2 // propagate tracks to best between initVertex and fCurrentVertex // preselect tracks (reject for |d0|>fNSigma*sigma w.r.t. best // between initVertex and fCurrentVertex) for(Int_t iter=0; iter<2; iter++) { if(fOnlyFitter && iter==0) continue; Int_t nTrksPrep = PrepareTracks(*trkTree,iter+1); if(fDebug) printf(" tracks prepared - iteration %d: %d\n",iter+1,nTrksPrep); if(nTrksPrep < fMinTracks) { if(fDebug) printf("TooFewTracks\n"); TooFewTracks(esdEvent); if(fDebug) fCurrentVertex->PrintStatus(); fTrkArray.Delete(); delete trkTree; f.Close(); gSystem->Unlink("VertexerTracks.root"); olddir->cd(); return fCurrentVertex; } // vertex finder if(!fOnlyFitter) { if(nTrksPrep==1){ if(fDebug) printf("Just one track\n"); OneTrackVertFinder(); }else{ switch (fAlgo) { case 1: StrLinVertexFinderMinDist(1); break; case 2: StrLinVertexFinderMinDist(0); break; case 3: HelixVertexFinder(); break; case 4: VertexFinder(1); break; case 5: VertexFinder(0); break; default: printf("Wrong algorithm\n"); break; } } if(fDebug) printf(" Vertex finding completed\n"); } // vertex fitter VertexFitter(fConstraint); if(fDebug) printf(" Vertex fit completed\n"); if(iter==0) fTrkArray.Delete(); } // end loop on the two iterations if(fConstraint) { if(fOnlyFitter) { fCurrentVertex->SetTitle("VertexerTracksWithConstraintOnlyFitter"); } else { fCurrentVertex->SetTitle("VertexerTracksWithConstraint"); } } else { fCurrentVertex->SetTitle("VertexerTracksNoConstraint"); } // set indices of used tracks UShort_t *indices = 0; AliESDtrack *ett = 0; if(fCurrentVertex->GetNContributors()>0) { indices = new UShort_t[fCurrentVertex->GetNContributors()]; for(Int_t jj=0;jj<(Int_t)fTrkArray.GetEntriesFast();jj++) { ett = (AliESDtrack*)fTrkArray.At(jj); indices[jj] = (UShort_t)ett->GetID(); } fCurrentVertex->SetIndices(fCurrentVertex->GetNContributors(),indices); } delete [] indices; delete trkTree; f.Close(); gSystem->Unlink("VertexerTracks.root"); olddir->cd(); fTrkArray.Delete(); if(fTrksToSkip) { delete [] fTrksToSkip; fTrksToSkip=NULL; } if(fDebug) fCurrentVertex->PrintStatus(); if(fDebug) fCurrentVertex->PrintIndices(); return fCurrentVertex; } //------------------------------------------------------------------------ Double_t AliVertexerTracks::GetDeterminant3X3(Double_t matr[][3]) { // Double_t det=matr[0][0]*matr[1][1]*matr[2][2]-matr[0][0]*matr[1][2]*matr[2][1]-matr[0][1]*matr[1][0]*matr[2][2]+matr[0][1]*matr[1][2]*matr[2][0]+matr[0][2]*matr[1][0]*matr[2][1]-matr[0][2]*matr[1][1]*matr[2][0]; return det; } //------------------------------------------------------------------------- void AliVertexerTracks::GetStrLinDerivMatrix(Double_t *p0,Double_t *p1,Double_t (*m)[3],Double_t *d) { // Double_t x12=p0[0]-p1[0]; Double_t y12=p0[1]-p1[1]; Double_t z12=p0[2]-p1[2]; Double_t kk=x12*x12+y12*y12+z12*z12; m[0][0]=2-2/kk*x12*x12; m[0][1]=-2/kk*x12*y12; m[0][2]=-2/kk*x12*z12; m[1][0]=-2/kk*x12*y12; m[1][1]=2-2/kk*y12*y12; m[1][2]=-2/kk*y12*z12; m[2][0]=-2/kk*x12*z12; m[2][1]=-2*y12*z12; m[2][2]=2-2/kk*z12*z12; d[0]=2*p0[0]-2/kk*p0[0]*x12*x12-2/kk*p0[2]*x12*z12-2/kk*p0[1]*x12*y12; d[1]=2*p0[1]-2/kk*p0[1]*y12*y12-2/kk*p0[0]*x12*y12-2/kk*p0[2]*z12*y12; d[2]=2*p0[2]-2/kk*p0[2]*z12*z12-2/kk*p0[0]*x12*z12-2/kk*p0[1]*z12*y12; } //-------------------------------------------------------------------------- void AliVertexerTracks::GetStrLinDerivMatrix(Double_t *p0,Double_t *p1,Double_t *sigmasq,Double_t (*m)[3],Double_t *d) { // Double_t x12=p1[0]-p0[0]; Double_t y12=p1[1]-p0[1]; Double_t z12=p1[2]-p0[2]; Double_t den= x12*x12*sigmasq[1]*sigmasq[2]+y12*y12*sigmasq[0]*sigmasq[2]+z12*z12*sigmasq[0]*sigmasq[1]; Double_t kk= 2*(x12*x12/sigmasq[0]+y12*y12/sigmasq[1]+z12*z12/sigmasq[2]); Double_t cc[3]; cc[0]=-x12/sigmasq[0]; cc[1]=-y12/sigmasq[1]; cc[2]=-z12/sigmasq[2]; Double_t ww=(-p0[0]*x12*sigmasq[1]*sigmasq[2]-p0[1]*y12*sigmasq[0]*sigmasq[2]-p0[2]*z12*sigmasq[0]*sigmasq[1])/den; Double_t ss= -p0[0]*cc[0]-p0[1]*cc[1]-p0[2]*cc[2]; Double_t aa[3]; aa[0]=x12*sigmasq[1]*sigmasq[2]/den; aa[1]=y12*sigmasq[0]*sigmasq[2]/den; aa[2]=z12*sigmasq[0]*sigmasq[1]/den; m[0][0]=aa[0]*(aa[0]*kk+2*cc[0])+2*cc[0]*aa[0]+2/sigmasq[0]; m[0][1]=aa[1]*(aa[0]*kk+2*cc[0])+2*cc[1]*aa[0]; m[0][2]=aa[2]*(aa[0]*kk+2*cc[0])+2*cc[2]*aa[0]; m[1][0]=aa[0]*(aa[1]*kk+2*cc[1])+2*cc[0]*aa[1]; m[1][1]=aa[1]*(aa[1]*kk+2*cc[1])+2*cc[1]*aa[1]+2/sigmasq[1]; m[1][2]=aa[2]*(aa[1]*kk+2*cc[1])+2*cc[2]*aa[1]; m[2][0]=aa[0]*(aa[2]*kk+2*cc[2])+2*cc[0]*aa[2]; m[2][1]=aa[1]*(aa[2]*kk+2*cc[2])+2*cc[1]*aa[2]; m[2][2]=aa[2]*(aa[2]*kk+2*cc[2])+2*cc[2]*aa[2]+2/sigmasq[2]; d[0]=-ww*(aa[0]*kk+2*cc[0])-2*ss*aa[0]+2*p0[0]/sigmasq[0]; d[1]=-ww*(aa[1]*kk+2*cc[1])-2*ss*aa[1]+2*p0[1]/sigmasq[1]; d[2]=-ww*(aa[2]*kk+2*cc[2])-2*ss*aa[2]+2*p0[2]/sigmasq[2]; } //-------------------------------------------------------------------------- Double_t AliVertexerTracks::GetStrLinMinDist(Double_t *p0,Double_t *p1,Double_t *x0) { // Double_t x12=p0[0]-p1[0]; Double_t y12=p0[1]-p1[1]; Double_t z12=p0[2]-p1[2]; Double_t x10=p0[0]-x0[0]; Double_t y10=p0[1]-x0[1]; Double_t z10=p0[2]-x0[2]; return ((x10*x10+y10*y10+z10*z10)*(x12*x12+y12*y12+z12*z12)-(x10*x12+y10*y12+z10*z12)*(x10*x12+y10*y12+z10*z12))/(x12*x12+y12*y12+z12*z12); } //--------------------------------------------------------------------------- void AliVertexerTracks::OneTrackVertFinder() { // find vertex for events with 1 track, using DCA to nominal beam axis if(fDebug) printf("Number of prepared tracks =%d - Call OneTrackVertFinder",fTrkArray.GetEntries()); AliESDtrack *track1; track1 = (AliESDtrack*)fTrkArray.At(0); Double_t field=GetFieldkG(); Double_t alpha=track1->GetAlpha(); Double_t mindist = TMath::Cos(alpha)*fNominalPos[0]+TMath::Sin(alpha)*fNominalPos[1]; Double_t pos[3],dir[3]; track1->GetXYZAt(mindist,field,pos); track1->GetPxPyPzAt(mindist,field,dir); AliStrLine *line1 = new AliStrLine(pos,dir); Double_t p1[3]={fNominalPos[0],fNominalPos[1],0.}; Double_t p2[3]={fNominalPos[0],fNominalPos[1],10.}; AliStrLine *zeta=new AliStrLine(p1,p2,kTRUE); Double_t crosspoint[3]={0.,0.,0.}; Double_t sigma=999.; Int_t nContrib=-1; Int_t retcode = zeta->Cross(line1,crosspoint); if(retcode>=0){ sigma=line1->GetDistFromPoint(crosspoint); nContrib=1; } delete zeta; delete line1; fVert.SetXYZ(crosspoint); fVert.SetDispersion(sigma); fVert.SetNContributors(nContrib); } //--------------------------------------------------------------------------- void AliVertexerTracks::HelixVertexFinder() { // Get estimate of vertex position in (x,y) from tracks DCA Double_t initPos[3]; initPos[2] = 0.; for(Int_t i=0;i<2;i++)initPos[i]=fNominalPos[i]; Double_t field=GetFieldkG(); Int_t nacc = (Int_t)fTrkArray.GetEntriesFast(); Double_t aver[3]={0.,0.,0.}; Double_t averquad[3]={0.,0.,0.}; Double_t sigmaquad[3]={0.,0.,0.}; Double_t sigma=0; Int_t ncombi = 0; AliESDtrack *track1; AliESDtrack *track2; Double_t distCA; Double_t x, par[5]; Double_t alpha, cs, sn; Double_t crosspoint[3]; for(Int_t i=0; iPropagateToDCA(track1,field); if(fDCAcut<=0 ||(fDCAcut>0&&distCAGetExternalParameters(x,par); alpha=track1->GetAlpha(); cs=TMath::Cos(alpha); sn=TMath::Sin(alpha); Double_t x1=x*cs - par[0]*sn; Double_t y1=x*sn + par[0]*cs; Double_t z1=par[1]; Double_t sx1=sn*sn*track1->GetSigmaY2(), sy1=cs*cs*track1->GetSigmaY2(); track2->GetExternalParameters(x,par); alpha=track2->GetAlpha(); cs=TMath::Cos(alpha); sn=TMath::Sin(alpha); Double_t x2=x*cs - par[0]*sn; Double_t y2=x*sn + par[0]*cs; Double_t z2=par[1]; Double_t sx2=sn*sn*track2->GetSigmaY2(), sy2=cs*cs*track2->GetSigmaY2(); Double_t sz1=track1->GetSigmaZ2(), sz2=track2->GetSigmaZ2(); Double_t wx1=sx2/(sx1+sx2), wx2=1.- wx1; Double_t wy1=sy2/(sy1+sy2), wy2=1.- wy1; Double_t wz1=sz2/(sz1+sz2), wz2=1.- wz1; crosspoint[0]=wx1*x1 + wx2*x2; crosspoint[1]=wy1*y1 + wy2*y2; crosspoint[2]=wz1*z1 + wz2*z2; ncombi++; for(Int_t jj=0;jj<3;jj++)aver[jj]+=crosspoint[jj]; for(Int_t jj=0;jj<3;jj++)averquad[jj]+=(crosspoint[jj]*crosspoint[jj]); } } } if(ncombi>0){ for(Int_t jj=0;jj<3;jj++){ initPos[jj] = aver[jj]/ncombi; averquad[jj]/=ncombi; sigmaquad[jj]=averquad[jj]-initPos[jj]*initPos[jj]; sigma+=sigmaquad[jj]; } sigma=TMath::Sqrt(TMath::Abs(sigma)); } else { Warning("HelixVertexFinder","Finder did not succed"); sigma=999; } fVert.SetXYZ(initPos); fVert.SetDispersion(sigma); fVert.SetNContributors(ncombi); } //---------------------------------------------------------------------------- Int_t AliVertexerTracks::PrepareTracks(TTree &trkTree,Int_t optImpParCut) { // // Propagate tracks to initial vertex position and store them in a TObjArray // Double_t maxd0rphi; Double_t maxd0z0 = fMaxd0z0; // default is 5 mm Int_t nTrks = 0; Double_t sigmaCurr[3]; Double_t normdistx,normdisty; Float_t d0z0[2],covd0z0[3]; Double_t sigma; Double_t field=GetFieldkG(); AliESDVertex *initVertex = new AliESDVertex(fNominalPos,fNominalCov,1,1); Int_t nEntries = (Int_t)trkTree.GetEntries(); if(!fTrkArray.IsEmpty()) fTrkArray.Delete(); if(fDebug) { printf(" PrepareTracks()\n"); } for(Int_t i=0; iRelateToVertex(initVertex,field,100.); } else { // optImpParCut==2 fCurrentVertex->GetSigmaXYZ(sigmaCurr); normdistx = TMath::Abs(fCurrentVertex->GetXv()-fNominalPos[0])/TMath::Sqrt(sigmaCurr[0]*sigmaCurr[0]+fNominalCov[0]); normdisty = TMath::Abs(fCurrentVertex->GetYv()-fNominalPos[1])/TMath::Sqrt(sigmaCurr[1]*sigmaCurr[1]+fNominalCov[2]); if(normdistx < 3. && normdisty < 3. && (sigmaCurr[0]+sigmaCurr[1])<(TMath::Sqrt(fNominalCov[0])+TMath::Sqrt(fNominalCov[2]))) { track->RelateToVertex(fCurrentVertex,field,100.); } else { track->RelateToVertex(initVertex,field,100.); } } track->GetImpactParameters(d0z0,covd0z0); sigma = TMath::Sqrt(covd0z0[0]); maxd0rphi = fNSigma*sigma; if(optImpParCut==1) maxd0rphi *= 5.; if(fDebug) printf("trk %d; lab %d; |d0| = %f; d0 cut = %f; |z0| = %f; |d0|oplus|z0| = %f; d0z0 cut = %f\n",i,track->GetLabel(),TMath::Abs(d0z0[0]),maxd0rphi,TMath::Abs(d0z0[1]),TMath::Sqrt(d0z0[0]*d0z0[0]+d0z0[1]*d0z0[1]),maxd0z0); // during iterations 1 and 2, if fConstraint=kFALSE, // select tracks with d0oplusz0 < maxd0z0 if(optImpParCut>=1 && !fConstraint && nEntries>=3 && fVert.GetNContributors()>0) { if(TMath::Sqrt(d0z0[0]*d0z0[0]+d0z0[1]*d0z0[1]) > maxd0z0) { if(fDebug) printf(" rejected\n"); delete track; continue; } } // select tracks with d0rphi < maxd0rphi if(optImpParCut>0 && TMath::Abs(d0z0[0]) > maxd0rphi) { if(fDebug) printf(" rejected\n"); delete track; continue; } fTrkArray.AddLast(track); nTrks++; } delete initVertex; return nTrks; } //--------------------------------------------------------------------------- AliESDVertex* AliVertexerTracks::RemoveTracksFromVertex(AliESDVertex *inVtx, TTree *trksTree, Float_t *diamondxy) { // // Removes tracks in trksTree from fit of inVtx // if(!strstr(inVtx->GetTitle(),"VertexerTracksWithConstraint")) { printf("ERROR: primary vertex has no constraint: cannot remove tracks\n"); return 0x0; } if(!strstr(inVtx->GetTitle(),"VertexerTracksWithConstraintOnlyFitter")) printf("WARNING: result of tracks' removal will be only approximately correct\n"); TMatrixD rv(3,1); rv(0,0) = inVtx->GetXv(); rv(1,0) = inVtx->GetYv(); rv(2,0) = inVtx->GetZv(); TMatrixD vV(3,3); Double_t cov[6]; inVtx->GetCovMatrix(cov); vV(0,0) = cov[0]; vV(0,1) = cov[1]; vV(1,0) = cov[1]; vV(1,1) = cov[2]; vV(0,2) = cov[3]; vV(2,0) = cov[3]; vV(1,2) = cov[4]; vV(2,1) = cov[4]; vV(2,2) = cov[5]; TMatrixD sumWi(TMatrixD::kInverted,vV); TMatrixD sumWiri(sumWi,TMatrixD::kMult,rv); Int_t nUsedTrks = inVtx->GetNContributors(); Double_t chi2 = inVtx->GetChi2(); AliESDtrack *track = 0; trksTree->SetBranchAddress("tracks",&track); Int_t ntrks = trksTree->GetEntries(); for(Int_t i=0;iGetEvent(i); if(!inVtx->UsesTrack(track->GetID())) { printf("track %d was not used in vertex fit\n",track->GetID()); continue; } Double_t alpha = track->GetAlpha(); Double_t xl = diamondxy[0]*TMath::Cos(alpha)+diamondxy[1]*TMath::Sin(alpha); track->AliExternalTrackParam::PropagateTo(xl,GetFieldkG()); // vector of track global coordinates TMatrixD ri(3,1); // covariance matrix of ri TMatrixD wWi(3,3); // get space point from track if(!TrackToPoint(track,ri,wWi)) continue; TMatrixD wWiri(wWi,TMatrixD::kMult,ri); sumWi -= wWi; sumWiri -= wWiri; // track chi2 TMatrixD deltar = rv; deltar -= ri; TMatrixD wWideltar(wWi,TMatrixD::kMult,deltar); Double_t chi2i = deltar(0,0)*wWideltar(0,0)+ deltar(1,0)*wWideltar(1,0)+ deltar(2,0)*wWideltar(2,0); // remove from total chi2 chi2 -= chi2i; nUsedTrks--; if(nUsedTrks<2) { printf("Trying to remove too many tracks!\n"); return 0x0; } } TMatrixD rvnew(3,1); TMatrixD vVnew(3,3); // new inverted of weights matrix TMatrixD invsumWi(TMatrixD::kInverted,sumWi); vVnew = invsumWi; // new position of primary vertex rvnew.Mult(vVnew,sumWiri); Double_t position[3]; position[0] = rvnew(0,0); position[1] = rvnew(1,0); position[2] = rvnew(2,0); cov[0] = vVnew(0,0); cov[1] = vVnew(0,1); cov[2] = vVnew(1,1); cov[3] = vVnew(0,2); cov[4] = vVnew(1,2); cov[5] = vVnew(2,2); // store data in the vertex object AliESDVertex *outVtx = new AliESDVertex(position,cov,chi2,nUsedTrks); outVtx->SetTitle(inVtx->GetTitle()); UShort_t *inindices = inVtx->GetIndices(); UShort_t *outindices = new UShort_t[outVtx->GetNContributors()]; Int_t j=0; Bool_t copyindex; for(Int_t k=0; kGetNIndices(); k++) { copyindex=kTRUE; for(Int_t l=0; lGetEvent(l); if(inindices[k]==track->GetID()) copyindex=kFALSE; } if(copyindex) { outindices[j] = inindices[k]; j++; } } outVtx->SetIndices(outVtx->GetNContributors(),outindices); delete [] outindices; if(fDebug) { printf("Vertex before removing tracks:\n"); inVtx->PrintStatus(); inVtx->PrintIndices(); printf("Vertex after removing tracks:\n"); outVtx->PrintStatus(); outVtx->PrintIndices(); } return outVtx; } //--------------------------------------------------------------------------- void AliVertexerTracks::SetSkipTracks(Int_t n,Int_t *skipped) { // // Mark the tracks not to be used in the vertex reconstruction. // Tracks are identified by AliESDtrack::GetID() // fNTrksToSkip = n; fTrksToSkip = new Int_t[n]; for(Int_t i=0;iGetXYZ(fNominalPos); vtx->GetCovMatrix(fNominalCov); SetConstraintOn(); return; } //--------------------------------------------------------------------------- void AliVertexerTracks::StrLinVertexFinderMinDist(Int_t optUseWeights) { AliESDtrack *track1; Double_t field=GetFieldkG(); const Int_t knacc = (Int_t)fTrkArray.GetEntriesFast(); TClonesArray *linarray = new TClonesArray("AliStrLine",1000); TClonesArray &lines = *linarray; for(Int_t i=0; iGetAlpha(); Double_t mindist = TMath::Cos(alpha)*fNominalPos[0]+TMath::Sin(alpha)*fNominalPos[1]; Double_t pos[3],dir[3],sigmasq[3]; track1->GetXYZAt(mindist,field,pos); track1->GetPxPyPzAt(mindist,field,dir); sigmasq[0]=TMath::Sin(alpha)*TMath::Sin(alpha)*track1->GetSigmaY2(); sigmasq[1]=TMath::Cos(alpha)*TMath::Cos(alpha)*track1->GetSigmaY2(); sigmasq[2]=track1->GetSigmaZ2(); TMatrixD ri(3,1); TMatrixD wWi(3,3); if(!TrackToPoint(track1,ri,wWi)) continue; Double_t wmat[9]; Int_t iel=0; for(Int_t ia=0;ia<3;ia++){ for(Int_t ib=0;ib<3;ib++){ wmat[iel]=wWi(ia,ib); iel++; } } new(lines[i]) AliStrLine(pos,sigmasq,wmat,dir); } fVert=TrackletVertexFinder(linarray,optUseWeights); linarray->Delete(); delete linarray; } //--------------------------------------------------------------------------- AliESDVertex AliVertexerTracks::TrackletVertexFinder(TClonesArray *lines, Int_t optUseWeights) { // Calculate the point at minimum distance to prepared tracks const Int_t knacc = (Int_t)lines->GetEntriesFast(); Double_t initPos[3]={0.,0.,0.}; Double_t (*vectP0)[3]=new Double_t [knacc][3]; Double_t (*vectP1)[3]=new Double_t [knacc][3]; Double_t sum[3][3]; Double_t dsum[3]={0,0,0}; TMatrixD sumWi(3,3); for(Int_t i=0;i<3;i++){ for(Int_t j=0;j<3;j++){ sum[i][j]=0; sumWi(i,j)=0.; } } for(Int_t i=0; iAt(i); Double_t p0[3],cd[3],sigmasq[3]; Double_t wmat[9]; line1->GetP0(p0); line1->GetCd(cd); line1->GetSigma2P0(sigmasq); line1->GetWMatrix(wmat); TMatrixD wWi(3,3); Int_t iel=0; for(Int_t ia=0;ia<3;ia++){ for(Int_t ib=0;ib<3;ib++){ wWi(ia,ib)=wmat[iel]; iel++; } } sumWi+=wWi; Double_t p1[3]={p0[0]+cd[0],p0[1]+cd[1],p0[2]+cd[2]}; vectP0[i][0]=p0[0]; vectP0[i][1]=p0[1]; vectP0[i][2]=p0[2]; vectP1[i][0]=p1[0]; vectP1[i][1]=p1[1]; vectP1[i][2]=p1[2]; Double_t matr[3][3]; Double_t dknow[3]; if(optUseWeights==0)GetStrLinDerivMatrix(p0,p1,matr,dknow); else GetStrLinDerivMatrix(p0,p1,sigmasq,matr,dknow); for(Int_t iii=0;iii<3;iii++){ dsum[iii]+=dknow[iii]; for(Int_t lj=0;lj<3;lj++) sum[iii][lj]+=matr[iii][lj]; } } TMatrixD invsumWi(TMatrixD::kInverted,sumWi); Double_t covmatrix[6]; covmatrix[0] = invsumWi(0,0); covmatrix[1] = invsumWi(0,1); covmatrix[2] = invsumWi(1,1); covmatrix[3] = invsumWi(0,2); covmatrix[4] = invsumWi(1,2); covmatrix[5] = invsumWi(2,2); Double_t vett[3][3]; Double_t det=GetDeterminant3X3(sum); Double_t sigma=0; if(det!=0){ for(Int_t zz=0;zz<3;zz++){ for(Int_t ww=0;ww<3;ww++){ for(Int_t kk=0;kk<3;kk++) vett[ww][kk]=sum[ww][kk]; } for(Int_t kk=0;kk<3;kk++) vett[kk][zz]=dsum[kk]; initPos[zz]=GetDeterminant3X3(vett)/det; } for(Int_t i=0; iGetAlpha(); if(rotAngle<0.) rotAngle += 2.*TMath::Pi(); Double_t cosRot = TMath::Cos(rotAngle); Double_t sinRot = TMath::Sin(rotAngle); ri(0,0) = t->GetX()*cosRot-t->GetY()*sinRot; ri(1,0) = t->GetX()*sinRot+t->GetY()*cosRot; ri(2,0) = t->GetZ(); if(!uUi3by3) { // matrix to go from global (x,y,z) to local (y,z); TMatrixD qQi(2,3); qQi(0,0) = -sinRot; qQi(0,1) = cosRot; qQi(0,2) = 0.; qQi(1,0) = 0.; qQi(1,1) = 0.; qQi(1,2) = 1.; // covariance matrix of local (y,z) - inverted Double_t cc[15]; t->GetExternalCovariance(cc); TMatrixD uUi(2,2); uUi(0,0) = cc[0]; uUi(0,1) = cc[1]; uUi(1,0) = cc[1]; uUi(1,1) = cc[2]; //printf(" Ui :\n"); //printf(" %f %f\n",uUi(0,0),uUi(0,1)); //printf(" %f %f\n",uUi(1,0),uUi(1,1)); if(uUi.Determinant() <= 0.) return kFALSE; TMatrixD uUiInv(TMatrixD::kInverted,uUi); // weights matrix: wWi = qQiT * uUiInv * qQi TMatrixD uUiInvQi(uUiInv,TMatrixD::kMult,qQi); TMatrixD m(qQi,TMatrixD::kTransposeMult,uUiInvQi); wWi = m; } else { if(fVert.GetNContributors()<1) AliFatal("Vertex from finder is empty"); // matrix to go from global (x,y,z) to local (x,y,z); TMatrixD qQi(3,3); qQi(0,0) = cosRot; qQi(0,1) = sinRot; qQi(0,2) = 0.; qQi(1,0) = -sinRot; qQi(1,1) = cosRot; qQi(1,2) = 0.; qQi(2,0) = 0.; qQi(2,1) = 0.; qQi(2,2) = 1.; // covariance of fVert along the track Double_t p[3],pt,ptot; t->GetPxPyPz(p); pt = TMath::Sqrt(p[0]*p[0]+p[1]*p[1]); ptot = TMath::Sqrt(pt*pt+p[2]*p[2]); Double_t cphi = p[0]/pt; //cos(phi)=px/pt Double_t sphi = p[1]/pt; //sin(phi)=py/pt Double_t clambda = pt/ptot; //cos(lambda)=pt/ptot Double_t slambda = p[2]/ptot; //sin(lambda)=pz/ptot Double_t covfVert[6]; fVert.GetCovMatrix(covfVert); Double_t covfVertalongt = covfVert[0]*cphi*cphi*clambda*clambda +covfVert[1]*2.*cphi*sphi*clambda*clambda +covfVert[3]*2.*cphi*clambda*slambda +covfVert[2]*sphi*sphi*clambda*clambda +covfVert[4]*2.*sphi*clambda*slambda +covfVert[5]*slambda*slambda; Double_t cc[15]; t->GetExternalCovariance(cc); // covariance matrix of local (x,y,z) - inverted TMatrixD uUi(3,3); uUi(0,0) = covfVertalongt * fnSigmaForUi00 * fnSigmaForUi00; if(fDebug) printf("=====> sqrtUi00 cm %f\n",TMath::Sqrt(uUi(0,0))); uUi(0,1) = 0.; uUi(0,2) = 0.; uUi(1,0) = 0.; uUi(1,1) = cc[0]; uUi(1,2) = cc[1]; uUi(2,0) = 0.; uUi(2,1) = cc[1]; uUi(2,2) = cc[2]; //printf(" Ui :\n"); //printf(" %f %f\n",uUi(0,0),uUi(0,1)); //printf(" %f %f\n",uUi(1,0),uUi(1,1)); if(uUi.Determinant() <= 0.) return kFALSE; TMatrixD uUiInv(TMatrixD::kInverted,uUi); // weights matrix: wWi = qQiT * uUiInv * qQi TMatrixD uUiInvQi(uUiInv,TMatrixD::kMult,qQi); TMatrixD m(qQi,TMatrixD::kTransposeMult,uUiInvQi); wWi = m; } return kTRUE; } //--------------------------------------------------------------------------- void AliVertexerTracks::TooFewTracks(const AliESDEvent* esdEvent) { // // When the number of tracks is < fMinTracks // // deal with vertices not found Double_t pos[3],err[3]; Int_t ncontr=0; pos[0] = fNominalPos[0]; err[0] = TMath::Sqrt(fNominalCov[0]); pos[1] = fNominalPos[1]; err[1] = TMath::Sqrt(fNominalCov[2]); pos[2] = esdEvent->GetVertex()->GetZv(); err[2] = esdEvent->GetVertex()->GetZRes(); if(err[0]>1. && esdEvent->GetVertex()->GetNContributors()<=0) ncontr = -1; // (x,y,z) = (0,0,0) if(err[0]>1. && esdEvent->GetVertex()->GetNContributors()>0) ncontr = -2; // (x,y,z) = (0,0,z_fromSPD) if(err[0]<1. && esdEvent->GetVertex()->GetNContributors()<=0) ncontr = -3; // (x,y,z) = (x_mean,y_mean,0) if(err[0]<1. && esdEvent->GetVertex()->GetNContributors()>0) ncontr = -4; // (x,y,z) = (x_mean,y_mean,z_fromSPD) fCurrentVertex = 0; fCurrentVertex = new AliESDVertex(pos,err); fCurrentVertex->SetNContributors(ncontr); if(fConstraint) { fCurrentVertex->SetTitle("VertexerTracksWithConstraint"); } else { fCurrentVertex->SetTitle("VertexerTracksNoConstraint"); } return; } //--------------------------------------------------------------------------- void AliVertexerTracks::VertexFinder(Int_t optUseWeights) { // Get estimate of vertex position in (x,y) from tracks DCA Double_t initPos[3]; initPos[2] = 0.; for(Int_t i=0;i<2;i++)initPos[i]=fNominalPos[i]; Int_t nacc = (Int_t)fTrkArray.GetEntriesFast(); Double_t aver[3]={0.,0.,0.}; Double_t aversq[3]={0.,0.,0.}; Double_t sigmasq[3]={0.,0.,0.}; Double_t sigma=0; Int_t ncombi = 0; AliESDtrack *track1; AliESDtrack *track2; Double_t pos[3],dir[3]; Double_t alpha,mindist; Double_t field=GetFieldkG(); for(Int_t i=0; iGetAlpha(); mindist = TMath::Cos(alpha)*fNominalPos[0]+TMath::Sin(alpha)*fNominalPos[1]; track1->GetXYZAt(mindist,field,pos); track1->GetPxPyPzAt(mindist,field,dir); AliStrLine *line1 = new AliStrLine(pos,dir); // AliStrLine *line1 = new AliStrLine(); // track1->ApproximateHelixWithLine(mindist,field,line1); for(Int_t j=i+1; jGetAlpha(); mindist = TMath::Cos(alpha)*fNominalPos[0]+TMath::Sin(alpha)*fNominalPos[1]; track2->GetXYZAt(mindist,field,pos); track2->GetPxPyPzAt(mindist,field,dir); AliStrLine *line2 = new AliStrLine(pos,dir); // AliStrLine *line2 = new AliStrLine(); // track2->ApproximateHelixWithLine(mindist,field,line2); Double_t distCA=line2->GetDCA(line1); //printf("%d %d %f\n",i,j,distCA); if(fDCAcut<=0 || (fDCAcut>0&&distCACross(line1,crosspoint); if(retcode>=0){ ncombi++; for(Int_t jj=0;jj<3;jj++)aver[jj]+=crosspoint[jj]; for(Int_t jj=0;jj<3;jj++)aversq[jj]+=(crosspoint[jj]*crosspoint[jj]); } } if(optUseWeights>0){ Int_t retcode = line1->CrossPoints(line2,pnt1,pnt2); if(retcode>=0){ Double_t cs, sn; alpha=track1->GetAlpha(); cs=TMath::Cos(alpha); sn=TMath::Sin(alpha); Double_t sx1=sn*sn*track1->GetSigmaY2(), sy1=cs*cs*track1->GetSigmaY2(); alpha=track2->GetAlpha(); cs=TMath::Cos(alpha); sn=TMath::Sin(alpha); Double_t sx2=sn*sn*track2->GetSigmaY2(), sy2=cs*cs*track2->GetSigmaY2(); Double_t sz1=track1->GetSigmaZ2(), sz2=track2->GetSigmaZ2(); Double_t wx1=sx2/(sx1+sx2), wx2=1.- wx1; Double_t wy1=sy2/(sy1+sy2), wy2=1.- wy1; Double_t wz1=sz2/(sz1+sz2), wz2=1.- wz1; crosspoint[0]=wx1*pnt1[0] + wx2*pnt2[0]; crosspoint[1]=wy1*pnt1[1] + wy2*pnt2[1]; crosspoint[2]=wz1*pnt1[2] + wz2*pnt2[2]; ncombi++; for(Int_t jj=0;jj<3;jj++)aver[jj]+=crosspoint[jj]; for(Int_t jj=0;jj<3;jj++)aversq[jj]+=(crosspoint[jj]*crosspoint[jj]); } } } delete line2; } delete line1; } if(ncombi>0){ for(Int_t jj=0;jj<3;jj++){ initPos[jj] = aver[jj]/ncombi; //printf("%f\n",initPos[jj]); aversq[jj]/=ncombi; sigmasq[jj]=aversq[jj]-initPos[jj]*initPos[jj]; sigma+=sigmasq[jj]; } sigma=TMath::Sqrt(TMath::Abs(sigma)); } else { Warning("VertexFinder","Finder did not succed"); sigma=999; } fVert.SetXYZ(initPos); fVert.SetDispersion(sigma); fVert.SetNContributors(ncombi); } //--------------------------------------------------------------------------- void AliVertexerTracks::VertexFitter(Bool_t useConstraint) { // // The optimal estimate of the vertex position is given by a "weighted // average of tracks positions". // Original method: V. Karimaki, CMS Note 97/0051 // Double_t initPos[3]; if(!fOnlyFitter) { fVert.GetXYZ(initPos); } else { initPos[0]=fNominalPos[0]; initPos[1]=fNominalPos[1]; initPos[2]=fNominalPos[2]; } Int_t nTrks = (Int_t)fTrkArray.GetEntries(); if(nTrks==1) useConstraint=kTRUE; if(fDebug) { printf("--- VertexFitter(): start\n"); printf(" Number of tracks in array: %d\n",nTrks); printf(" Minimum # tracks required in fit: %d\n",fMinTracks); printf(" Vertex position after finder: %f,%f,%f\n",initPos[0],initPos[1],initPos[2]); if(useConstraint) printf(" This vertex will be used in fit: (%f+-%f,%f+-%f)\n",fNominalPos[0],TMath::Sqrt(fNominalCov[0]),fNominalPos[1],TMath::Sqrt(fNominalCov[2])); } // special treatment for few-tracks fits (e.g. secondary vertices) Bool_t uUi3by3 = kFALSE; if(nTrks<5 && !useConstraint) uUi3by3 = kTRUE; Int_t i,j,k,step=0; TMatrixD rv(3,1); TMatrixD vV(3,3); rv(0,0) = initPos[0]; rv(1,0) = initPos[1]; rv(2,0) = 0.; Double_t xlStart,alpha; Int_t nUsedTrks; Double_t chi2,chi2i,chi2b; AliESDtrack *t = 0; Int_t failed = 0; // initial vertex covariance matrix TMatrixD vVb(3,3); vVb(0,0) = fNominalCov[0]; vVb(0,1) = fNominalCov[1]; vVb(0,2) = 0.; vVb(1,0) = fNominalCov[1]; vVb(1,1) = fNominalCov[2]; vVb(1,2) = 0.; vVb(2,0) = 0.; vVb(2,1) = 0.; vVb(2,2) = fNominalCov[5]; TMatrixD vVbInv(TMatrixD::kInverted,vVb); TMatrixD rb(3,1); rb(0,0) = fNominalPos[0]; rb(1,0) = fNominalPos[1]; rb(2,0) = fNominalPos[2]; TMatrixD vVbInvrb(vVbInv,TMatrixD::kMult,rb); // 2 steps: // 1st - estimate of vtx using all tracks // 2nd - estimate of global chi2 for(step=0; step<2; step++) { if(fDebug) printf(" step = %d\n",step); chi2 = 0.; nUsedTrks = 0; if(step==1) { initPos[0]=rv(0,0); initPos[0]=rv(1,0); } TMatrixD sumWiri(3,1); TMatrixD sumWi(3,3); for(i=0; i<3; i++) { sumWiri(i,0) = 0.; for(j=0; j<3; j++) sumWi(j,i) = 0.; } // mean vertex constraint if(useConstraint) { for(i=0;i<3;i++) { sumWiri(i,0) += vVbInvrb(i,0); for(k=0;k<3;k++) sumWi(i,k) += vVbInv(i,k); } // chi2 TMatrixD deltar = rv; deltar -= rb; TMatrixD vVbInvdeltar(vVbInv,TMatrixD::kMult,deltar); chi2b = deltar(0,0)*vVbInvdeltar(0,0)+ deltar(1,0)*vVbInvdeltar(1,0)+ deltar(2,0)*vVbInvdeltar(2,0); chi2 += chi2b; } // loop on tracks for(k=0; kGetAlpha(); xlStart = initPos[0]*TMath::Cos(alpha)+initPos[1]*TMath::Sin(alpha); // to vtxSeed (from finder) t->AliExternalTrackParam::PropagateTo(xlStart,GetFieldkG()); // vector of track global coordinates TMatrixD ri(3,1); // covariance matrix of ri TMatrixD wWi(3,3); // get space point from track if(!TrackToPoint(t,ri,wWi,uUi3by3)) continue; TMatrixD wWiri(wWi,TMatrixD::kMult,ri); // track chi2 TMatrixD deltar = rv; deltar -= ri; TMatrixD wWideltar(wWi,TMatrixD::kMult,deltar); chi2i = deltar(0,0)*wWideltar(0,0)+ deltar(1,0)*wWideltar(1,0)+ deltar(2,0)*wWideltar(2,0); // add to total chi2 chi2 += chi2i; sumWiri += wWiri; sumWi += wWi; nUsedTrks++; } // end loop on tracks if(nUsedTrks < fMinTracks) { failed=1; continue; } Double_t determinant = sumWi.Determinant(); //cerr<<" determinant: "<PrintStatus(); printf("--- VertexFitter(): finish\n"); } return; } //---------------------------------------------------------------------------- AliESDVertex* AliVertexerTracks::VertexForSelectedTracks(TTree *trkTree,Bool_t optUseFitter,Bool_t optPropagate) { // // Return vertex from tracks in trkTree // SetConstraintOff(); // get tracks and propagate them to initial vertex position Int_t nTrksPrep = PrepareTracks(*trkTree,0); if(nTrksPrep < TMath::Max(2,fMinTracks) ) { if(fDebug) printf("TooFewTracks\n"); fCurrentVertex = new AliESDVertex(0.,0.,-1); return fCurrentVertex; } switch (fAlgo) { case 1: StrLinVertexFinderMinDist(1); break; case 2: StrLinVertexFinderMinDist(0); break; case 3: HelixVertexFinder(); break; case 4: VertexFinder(1); break; case 5: VertexFinder(0); break; default: printf("Wrong algorithm\n"); break; } if(fDebug) printf(" Vertex finding completed\n"); // vertex fitter if(optUseFitter){ //SetVtxStart(&fVert); VertexFitter(fConstraint); if(fDebug) printf(" Vertex fit completed\n"); }else{ Double_t position[3]={fVert.GetXv(),fVert.GetYv(),fVert.GetZv()}; Double_t covmatrix[6]; fVert.GetCovMatrix(covmatrix); Double_t chi2=99999.; Int_t nUsedTrks=fVert.GetNContributors(); fCurrentVertex = new AliESDVertex(position,covmatrix,chi2,nUsedTrks); } fCurrentVertex->SetDispersion(fVert.GetDispersion()); // set indices of used tracks and propagate track to found vertex UShort_t *indices = 0; AliESDtrack *eta = 0; if(fCurrentVertex->GetNContributors()>0) { indices = new UShort_t[fCurrentVertex->GetNContributors()]; for(Int_t jj=0;jj<(Int_t)fTrkArray.GetEntriesFast();jj++) { eta = (AliESDtrack*)fTrkArray.At(jj); indices[jj] = (UShort_t)eta->GetID(); if(optPropagate&&optUseFitter){ if(TMath::Sqrt(fCurrentVertex->GetXv()*fCurrentVertex->GetXv()+fCurrentVertex->GetYv()*fCurrentVertex->GetYv())<3.) { eta->RelateToVertex(fCurrentVertex,GetFieldkG(),100.); if(fDebug) printf("Track %d propagated to found vertex\n",jj); }else{ AliWarning("Found vertex outside beam pipe!"); } } } fCurrentVertex->SetIndices(fCurrentVertex->GetNContributors(),indices); } delete [] indices; fTrkArray.Delete(); return fCurrentVertex; } //---------------------------------------------------------------------------- AliESDVertex* AliVertexerTracks::VertexForSelectedTracks(TObjArray *trkArray,Bool_t optUseFitter, Bool_t optPropagate) { // // Return vertex from array of tracks // // get tracks and propagate them to initial vertex position Int_t nTrks = trkArray->GetEntriesFast(); if(nTrks < TMath::Max(2,fMinTracks) ) { if(fDebug) printf("TooFewTracks\n"); fCurrentVertex = new AliESDVertex(0.,0.,-1); return fCurrentVertex; } TDirectory * olddir = gDirectory; TFile f("VertexerTracks.root","recreate"); TTree *trkTree = new TTree("TreeT","tracks"); AliESDtrack *esdTrack = 0; trkTree->Branch("tracks","AliESDtrack",&esdTrack); for(Int_t i=0; iAt(i); trkTree->Fill(); } AliESDVertex *vtx = VertexForSelectedTracks(trkTree,optUseFitter,optPropagate); delete trkTree; f.Close(); gSystem->Unlink("VertexerTracks.root"); olddir->cd(); return vtx; } //--------------------------------------------------------------------------