HMPID/AliHMPIDTracker.cxx

   1 #include "AliHMPIDTracker.h"     //class header
   2 #include "AliHMPIDCluster.h"     //GetTrackPoint(),PropagateBack()
   3 #include "AliHMPIDParam.h"       //GetTrackPoint(),PropagateBack()
   4 #include "AliHMPIDRecon.h"       //PropagateBack()
   5 #include <AliESD.h>              //PropagateBack()
   6 #include <AliRun.h>              //GetTrackPoint(),PropagateBack()
   7 #include <AliTrackPointArray.h>  //GetTrackPoint()
   8 #include <AliAlignObj.h>         //GetTrackPoint()
   9 ClassImp(AliHMPIDTracker)
  10 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  11 Bool_t AliHMPIDTracker::GetTrackPoint(Int_t idx, AliTrackPoint& point) const
  12 {
  13 // Interface callback methode invoked from AliReconstruction::WriteAlignmentData() to get position of MIP cluster in MARS associated to a current track.
  14 // MIP cluster is reffered by index which is stored in AliESDtrack  ???????
  15 // Arguments: idx- cluster index which is stored by HMPID in AliESDtrack
  16 //            point- reference to the object where to store the point
  17 //   Returns: status of operation  if FALSE then AliReconstruction::WriteAlignmentData() do not store this point to array of points for current track.
  18   if(idx<0) return kFALSE; //no MIP cluster assigned to this track in PropagateBack()
  19   Int_t iCham=idx/1000000;
  20   Int_t iClu=idx%1000000;
  21   point.SetVolumeID(AliAlignObj::LayerToVolUID(AliAlignObj::kHMPID,iCham-1));//layer and chamber number
  22   AliHMPID *pRich=((AliHMPID*)gAlice->GetDetector("HMPID"));
  23   AliHMPIDCluster *pClu=(AliHMPIDCluster*)pRich->CluLst(iCham)->UncheckedAt(iClu);//get pointer to cluster
  24   Double_t mars[3];
  25   AliHMPIDParam::Instance()->Lors2Mars(iCham,pClu->X(),pClu->Y(),mars);
  26   point.SetXYZ(mars[0],mars[1],mars[2]);
  27   return kTRUE;
  28 }
  29 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  30 Int_t AliHMPIDTracker::LoadClusters(TTree *pCluTree)
  31 {
  32 // Interface callback methode invoked from AliReconstruction::RunTracking() to load HMPID clusters before PropagateBack() gets control
  33 // Arguments: pCluTree- pointer to clusters tree got by AliHMPIDLoader::LoadRecPoints("read") then AliHMPIDLoader::TreeR()
  34 //   Returns: error code (currently ignored in AliReconstruction::RunTraking())
  35   AliDebug(1,"Start.");  pCluTree->GetEntry(0);  AliDebug(1,"Stop."); return 0;
  36 }
  37 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  38 Int_t AliHMPIDTracker::Recon(AliESD *pESD,TObjArray *pCluAll)
  39 {
  40 // Interface callback methode invoked by AliRecontruction::RunTracking() during tracking after TOF. It's done just once per event
  41 // Arguments: pESD - pointer to Event Summary Data class instance which contains a list of tracks
  42 //   Returns: error code, 0 if no errors
  43   Int_t iNtracks=pESD->GetNumberOfTracks();  AliDebugClass(1,Form("Start with %i tracks",iNtracks));
  44   AliHMPIDRecon recon;                                                        //instance of reconstruction class, nothing important in ctor
  45
  46   AliHMPIDParam *pParam=AliHMPIDParam::Instance();
  47
  48   for(Int_t iTrk=0;iTrk<iNtracks;iTrk++){                                                        //ESD tracks loop
  49     AliESDtrack *pTrk = pESD->GetTrack(iTrk);                                                    //get next reconstructed track
  50
  51     Float_t xRa=0,yRa=0,xPc=0,yPc=0,th=0,ph=0;                                                   //track intersection point and angles, LORS
  52     Int_t iCh=-1;                                                                                //intersected chamber
  53     for(Int_t i=0;i<7;i++){                                                                      //chambers loop
  54       Double_t p1[3],n1[3]; pParam->Norm(i,n1); pParam->Lors2Mars(i,0,0,p1,AliHMPIDParam::kRad);  //point & norm  for RAD
  55       Double_t p2[3],n2[3]; pParam->Norm(i,n2); pParam->Lors2Mars(i,0,0,p2,AliHMPIDParam::kPc);   //point & norm  for PC
  56
  57       if(pTrk->Intersect(p1,n1,-GetBz())==kFALSE) continue;                                      //try to intersect track with the middle of radiator
  58       if(pTrk->Intersect(p2,n2,-GetBz())==kFALSE) continue;                                      //try to intersect track with PC
  59
  60       pParam->Mars2LorsVec(i,n1,th,ph);                                                          //track angles
  61       pParam->Mars2Lors   (i,p1,xRa,yRa);                                                        //TRKxRAD position
  62       pParam->Mars2Lors   (i,p2,xPc,yPc);                                                        //TRKxPC position
  63
  64       if(AliHMPIDDigit::IsInside(xPc,yPc)==kFALSE) continue;                                      //not in active area
  65       iCh=i;
  66       break;
  67     }//chambers loop
  68
  69     if(iCh==-1) continue;                                                                  //no intersection at all, go after next track
  70
  71     TClonesArray *pCluLst=(TClonesArray *)pCluAll->At(iCh);                                //get clusters list for intersected chamber
  72
  73     Double_t    dMin=999;                                                                  //distance between track-PC intersection point and current cluster
  74     Int_t   iMip=-1;                                                                       //index of cluster nearest to intersection point
  75     for(Int_t iClu=0;iClu<pCluLst->GetEntries();iClu++){                                   //clusters loop for intersected chamber
  76       AliHMPIDCluster *pClu=(AliHMPIDCluster*)pCluLst->At(iClu);                             //get pointer to current cluster
  77       if(pClu->Q()<100) continue;                                                          //QDC is incompartible with mip, go after another one
  78
  79       Float_t dX=xPc-pClu->X();                                                            //distance between current cluster and intersection point
  80       Float_t dY=yPc-pClu->Y();
  81       Float_t d =TMath::Sqrt(dX*dX+dY*dY);
  82
  83       if( d < dMin) {iMip=iClu; dMin=d;}                                                   //current cluster is closer, overwrite data for min cluster
  84     }//clusters loop for intersected chamber
  85
  86                    pTrk->SetHMPIDtrk      (xPc,yPc,th,ph);                                  //store track info
  87     if(iMip==-1)  {pTrk->SetHMPIDsignal   (kMipQdcCut);  continue;}                         //no clusters with QDC more the threshold at all
  88
  89     AliHMPIDCluster *pMipClu=(AliHMPIDCluster*)pCluLst->At(iMip);                            //take mip cluster
  90
  91                    pTrk->SetHMPIDmip      (pMipClu->X(),pMipClu->Y(),pMipClu->Q());          //store mip info
  92     if(dMin>1)    {pTrk->SetHMPIDsignal   (kMipDistCut); continue;}                          //closest cluster with enough charge is still too far
  93                    pTrk->SetHMPIDcluIdx   (iCh,iMip);                                        //set mip cluster index
  94   recon.SetTrack(th,ph,xRa,yRa); Int_t iNphot=0;                                            //initialize track parameters
  95                    pTrk->SetHMPIDsignal   (recon.CkovAngle(pCluLst,iNphot));                 //search for Cerenkov angle for this track
  96                    pTrk->SetHMPIDchi2     (recon.CkovSigma2());                              //error squared
  97                    pTrk->SetHMPIDmip      (pMipClu->X(),pMipClu->Y(),pMipClu->Q(),iMip);     //info on mip cluster + n. phot.
  98  }//ESD tracks loop
  99   AliDebugClass(1,"Stop pattern recognition");
 100   return 0; // error code: 0=no error;
 101 }//PropagateBack()
 102 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++