// for single chamber //
//////////////////////////////////////////////////////////////////////////
-#include "AliHMPIDRecon.h" //class header
+#include "AliHMPIDRecon.h" //class header
#include "AliHMPIDCluster.h" //CkovAngle()
-#include <TRotation.h> //TracePhoton()
-#include <TH1D.h> //HoughResponse()
-#include <TClonesArray.h> //CkovAngle()
-#include <AliESDtrack.h> //CkovAngle()
-
-const Double_t AliHMPIDRecon::fgkRadThick=1.5;
-const Double_t AliHMPIDRecon::fgkWinThick=0.5;
-const Double_t AliHMPIDRecon::fgkGapThick=8.0;
-const Double_t AliHMPIDRecon::fgkRadIdx =1.292;
-const Double_t AliHMPIDRecon::fgkWinIdx =1.5787;
-const Double_t AliHMPIDRecon::fgkGapIdx =1.0005;
-
+#include <TRotation.h> //TracePhot()
+#include <TH1D.h> //HoughResponse()
+#include <TClonesArray.h> //CkovAngle()
+#include <AliESDtrack.h> //CkovAngle()
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
-AliHMPIDRecon::AliHMPIDRecon():TTask("RichRec","RichPat"),
+AliHMPIDRecon::AliHMPIDRecon():
+ TTask("RichRec","RichPat"),
fPhotCnt(-1),
+ fPhotFlag(0x0),
+ fPhotCkov(0x0),
+ fPhotPhi(0x0),
+ fPhotWei(0x0),
fCkovSigma2(0),
fIsWEIGHT(kFALSE),
fDTheta(0.001),
fWindowWidth(0.045),
- fTrkDir(TVector3(0,0,1)),fTrkPos(TVector2(30,40))
+ fRingArea(0),
+ fRingAcc(0),
+ fTrkDir(0,0,1), // Just for test
+ fTrkPos(30,40), // Just for test
+ fMipPos(0,0),
+ fPc(0,0),
+ fParam(AliHMPIDParam::Instance())
{
-// main ctor
- for (Int_t i=0; i<3000; i++) {
- fPhotFlag[i] = 0;
- fPhotCkov[i] = -1;
- fPhotPhi [i] = -1;
- fPhotWei [i] = 0;
- }
+//..
+//init of data members
+//..
+
+ fParam->SetRefIdx(fParam->MeanIdxRad()); // initialization of ref index to a default one
+}
+//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+void AliHMPIDRecon::InitVars(Int_t n)
+{
+//..
+//Init some variables
+//..
+ if(n<0) return;
+ fPhotFlag = new Int_t[n];
+ fPhotCkov = new Double_t[n];
+ fPhotPhi = new Double_t[n];
+ fPhotWei = new Double_t[n];
+//
}
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
-void AliHMPIDRecon::CkovAngle(AliESDtrack *pTrk,TClonesArray *pCluLst)
+void AliHMPIDRecon::DeleteVars()const
+{
+//..
+//Delete variables
+//..
+ delete fPhotFlag;
+ delete fPhotCkov;
+ delete fPhotPhi;
+ delete fPhotWei;
+}
+//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+void AliHMPIDRecon::CkovAngle(AliESDtrack *pTrk,TClonesArray *pCluLst,Double_t nmean,Double_t qthre)
{
// Pattern recognition method based on Hough transform
// Arguments: pTrk - track for which Ckov angle is to be found
// pCluLst - list of clusters for this chamber
// Returns: - track ckov angle, [rad],
-
- if(pCluLst->GetEntries()>200) fIsWEIGHT = kTRUE; // offset to take into account bkg in reconstruction
- else fIsWEIGHT = kFALSE;
-
- // Photon Flag: Flag = 0 initial set; Flag = 1 good candidate (charge compatible with photon); Flag = 2 photon used for the ring;
- Float_t xPc,yPc,th,ph; pTrk->GetHMPIDtrk(xPc,yPc,th,ph); SetTrack(xPc,yPc,th,ph); //initialize this track
+
+ const Int_t nMinPhotAcc = 3; // Minimum number of photons required to perform the pattern recognition
+ Int_t nClusTot = pCluLst->GetEntries();
+ if(nClusTot>fParam->MultCut()) fIsWEIGHT = kTRUE; // offset to take into account bkg in reconstruction
+ else fIsWEIGHT = kFALSE;
+
+ InitVars(nClusTot);
+
+ Float_t xRa,yRa,th,ph;
+ pTrk->GetHMPIDtrk(xRa,yRa,th,ph); //initialize this track: th and ph angles at middle of RAD
+ SetTrack(xRa,yRa,th,ph);
+
+ fParam->SetRefIdx(nmean);
+
Float_t dMin=999,mipX=-1,mipY=-1;Int_t chId=-1,mipId=-1,mipQ=-1;
fPhotCnt=0;
for (Int_t iClu=0; iClu<pCluLst->GetEntriesFast();iClu++){//clusters loop
AliHMPIDCluster *pClu=(AliHMPIDCluster*)pCluLst->UncheckedAt(iClu); //get pointer to current cluster
chId=pClu->Ch();
- if(pClu->Q()>100){ //charge compartible with MIP clusters
- Float_t dX=xPc-pClu->X(),dY=yPc-pClu->Y(),d =TMath::Sqrt(dX*dX+dY*dY); //distance between current cluster and intersection point
- if( d < dMin) {mipId=iClu; dMin=d;mipX=pClu->X();mipY=pClu->Y();mipQ=(Int_t)pClu->Q();}//current cluster is closer, overwrite data for min cluster
- }else{ //charge compartible with photon cluster
- fPhotCkov[fPhotCnt]=FindPhotCkov(pClu->X(),pClu->Y()); //find ckov angle for this photon candidate
- fPhotCnt++; //increment counter of photon candidates
+ if(pClu->Q()>qthre){ //charge compartible with MIP clusters
+ Float_t dX=fPc.X()-pClu->X(),dY=fPc.Y()-pClu->Y(),d =TMath::Sqrt(dX*dX+dY*dY); //distance between current cluster and intersection point
+ if( d < dMin) {mipId=iClu; dMin=d;mipX=pClu->X();mipY=pClu->Y();mipQ=(Int_t)pClu->Q();} //current cluster is closer, overwrite data for min cluster
+ }else{ //charge compatible with photon cluster
+ Double_t thetaCer,phiCer;
+ if(FindPhotCkov(pClu->X(),pClu->Y(),thetaCer,phiCer)){ //find ckov angle for this photon candidate
+ fPhotCkov[fPhotCnt]=thetaCer; //actual theta Cerenkov (in TRS)
+ fPhotPhi [fPhotCnt]=phiCer; //actual phi Cerenkov (in TRS): -pi to come back to "unusual" ref system (X,Y,-Z)
+ //PH Printf("photon n. %i reconstructed theta = %f",fPhotCnt,fPhotCkov[fPhotCnt]);
+ fPhotCnt++; //increment counter of photon candidates
+ }
}
}//clusters loop
- Int_t iNacc=FlagPhot(HoughResponse()); //flag photons according to individual theta ckov with respect to most probable
-
- pTrk->SetHMPIDmip (mipX,mipY,mipQ,iNacc); //store mip info
-
- if(mipId==-1) {pTrk->SetHMPIDsignal (kMipQdcCut); return;} //no clusters with QDC more the threshold at all
- if(dMin>1) {pTrk->SetHMPIDsignal (kMipDistCut); return;} //closest cluster with enough charge is still too far from intersection
- pTrk->SetHMPIDcluIdx(chId,mipId);
- if(iNacc<1) pTrk->SetHMPIDsignal(kNoPhotAccept); //no photon candidates is accepted
- else pTrk->SetHMPIDsignal(FindRingCkov(pCluLst->GetEntries())); //find best Theta ckov for ring i.e. track
- pTrk->SetHMPIDchi2(fCkovSigma2); //error squared
+ if(fPhotCnt<=nMinPhotAcc) { //no reconstruction with <=3 photon candidates
+ pTrk->SetHMPIDsignal(kNoPhotAccept); //set the appropriate flag
+ pTrk->SetHMPIDmip(mipX,mipY,mipQ,fPhotCnt); //store mip info
+ pTrk->SetHMPIDcluIdx(-1,-1); //set index of cluster
+ return;
+ }
+
+ if(mipId==-1) {
+ pTrk->SetHMPIDcluIdx(chId,9999); //set index of cluster
+ pTrk->SetHMPIDsignal(kMipQdcCut);
+ return;
+ } //no clusters with QDC more the threshold at all
+ pTrk->SetHMPIDcluIdx(chId,mipId); //set index of cluster
+ if(dMin>fParam->DistCut()) {pTrk->SetHMPIDsignal(kMipDistCut); return;} //closest cluster with enough charge is still too far from intersection
+
+ fMipPos.Set(mipX,mipY);
+
+
+//PATTERN RECOGNITION STARTED:
+
+ Int_t iNrec=FlagPhot(HoughResponse()); //flag photons according to individual theta ckov with respect to most probable
+ pTrk->SetHMPIDmip(mipX,mipY,mipQ,iNrec); //store mip info
+
+ if(iNrec<1){
+ pTrk->SetHMPIDsignal(kNoPhotAccept); //no photon candidates are accepted
+ return;
+ }
+ Double_t thetaC = FindRingCkov(pCluLst->GetEntries()); //find the best reconstructed theta Cherenkov
+// FindRingGeom(thetaC,2);
+ pTrk->SetHMPIDsignal(thetaC); //store theta Cherenkov
+ pTrk->SetHMPIDchi2(fCkovSigma2); //store errors squared
-}//ThetaCerenkov()
+ DeleteVars();
+}//CkovAngle()
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
-Double_t AliHMPIDRecon::FindPhotCkov(Double_t cluX,Double_t cluY)
+Bool_t AliHMPIDRecon::FindPhotCkov(Double_t cluX,Double_t cluY,Double_t &thetaCer,Double_t &phiCer)
{
// Finds Cerenkov angle for this photon candidate
// Arguments: cluX,cluY - position of cadidate's cluster
-// Returns: Cerenkov angle
+// Returns: Cerenkov angle
- TVector2 pos(cluX,cluY); Double_t cluR=(pos-fTrkPos).Mod(); Double_t phi=FindPhotPhi(cluX,cluY);
- Double_t ckov1=0,ckov2=0.75;
- const Double_t kTol=0.05;
+ TVector3 dirCkov;
+
+ Double_t zRad= -0.5*fParam->RadThick()-0.5*fParam->WinThick(); //z position of middle of RAD
+ TVector3 rad(fTrkPos.X(),fTrkPos.Y(),zRad); //impact point at middle of RAD
+ TVector3 pc(cluX,cluY,0.5*fParam->WinThick()+fParam->GapIdx()); //mip at PC
+ Double_t cluR = TMath::Sqrt((cluX-fTrkPos.X())*(cluX-fTrkPos.X())+
+ (cluY-fTrkPos.Y())*(cluY-fTrkPos.Y()));//ref. distance impact RAD-CLUSTER
+ Double_t phi=(pc-rad).Phi(); //phi of photon
+
+ Double_t ckov1=0;
+ Double_t ckov2=0.75+fTrkDir.Theta(); //start to find theta cerenkov in DRS
+ const Double_t kTol=0.01;
Int_t iIterCnt = 0;
while(1){
- if(iIterCnt>=50) return -1;
+ if(iIterCnt>=50) return kFALSE;
Double_t ckov=0.5*(ckov1+ckov2);
- Double_t dist=cluR-TracePhot(ckov,phi,pos); iIterCnt++; //get distance between trial point and cluster position
- if (dist> kTol) ckov1=ckov; //cluster @ larger ckov
+ dirCkov.SetMagThetaPhi(1,ckov,phi);
+ TVector2 posC=TraceForward(dirCkov); //trace photon with actual angles
+ Double_t dist=cluR-(posC-fTrkPos).Mod(); //get distance between trial point and cluster position
+ if(posC.X()==-999) dist = - 999; //total reflection problem
+ iIterCnt++; //counter step
+ if (dist> kTol) ckov1=ckov; //cluster @ larger ckov
else if(dist<-kTol) ckov2=ckov; //cluster @ smaller ckov
- else return ckov; //precision achived
+ else{ //precision achived: ckov in DRS found
+ dirCkov.SetMagThetaPhi(1,ckov,phi); //
+ Lors2Trs(dirCkov,thetaCer,phiCer); //find ckov (in TRS:the effective Cherenkov angle!)
+ return kTRUE;
+ }
}
}//FindPhotTheta()
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
-Double_t AliHMPIDRecon::FindPhotPhi(Double_t cluX,Double_t cluY)
+TVector2 AliHMPIDRecon::TraceForward(TVector3 dirCkov)const
{
-// Finds phi angle og photon candidate by considering the cluster's position of this candudate w.r.t track position
+ //Trace forward a photon from (x,y) up to PC
+ // Arguments: dirCkov photon vector in LORS
+ // Returns: pos of traced photon at PC
- Double_t emiss=0;
- return fPhotPhi[fPhotCnt]=TMath::ATan2(cluY-fTrkPos.Y()-emiss*TMath::Tan(fTrkDir.Theta())*TMath::Sin(fTrkDir.Phi()),
- cluX-fTrkPos.X()-emiss*TMath::Tan(fTrkDir.Theta())*TMath::Cos(fTrkDir.Phi()));
+ TVector2 pos(-999,-999);
+ Double_t thetaCer = dirCkov.Theta();
+ if(thetaCer > TMath::ASin(1./fParam->GetRefIdx())) return pos; //total refraction on WIN-GAP boundary
+ Double_t zRad= -0.5*fParam->RadThick()-0.5*fParam->WinThick(); //z position of middle of RAD
+ TVector3 posCkov(fTrkPos.X(),fTrkPos.Y(),zRad); //RAD: photon position is track position @ middle of RAD
+ Propagate(dirCkov,posCkov, -0.5*fParam->WinThick()); //go to RAD-WIN boundary
+ Refract (dirCkov, fParam->GetRefIdx(),fParam->WinIdx()); //RAD-WIN refraction
+ Propagate(dirCkov,posCkov, 0.5*fParam->WinThick()); //go to WIN-GAP boundary
+ Refract (dirCkov, fParam->WinIdx(),fParam->GapIdx()); //WIN-GAP refraction
+ Propagate(dirCkov,posCkov,0.5*fParam->WinThick()+fParam->GapThick()); //go to PC
+ pos.Set(posCkov.X(),posCkov.Y());
+ return pos;
+}//TraceForward()
+//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+void AliHMPIDRecon::Lors2Trs(TVector3 dirCkov,Double_t &thetaCer,Double_t &phiCer)const
+{
+ //Theta Cerenkov reconstruction
+ // Arguments: dirCkov photon vector in LORS
+ // Returns: thetaCer of photon in TRS
+ // phiCer of photon in TRS
+// TVector3 dirTrk;
+// dirTrk.SetMagThetaPhi(1,fTrkDir.Theta(),fTrkDir.Phi());
+// Double_t thetaCer = TMath::ACos(dirCkov*dirTrk);
+ TRotation mtheta; mtheta.RotateY(-fTrkDir.Theta());
+ TRotation mphi; mphi.RotateZ(-fTrkDir.Phi());
+ TRotation mrot=mtheta*mphi;
+ TVector3 dirCkovTRS;
+ dirCkovTRS=mrot*dirCkov;
+ phiCer = dirCkovTRS.Phi(); //actual value of the phi of the photon
+ thetaCer= dirCkovTRS.Theta(); //actual value of thetaCerenkov of the photon
}
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
-Double_t AliHMPIDRecon::FindRingArea(Double_t ckovAng)const
+void AliHMPIDRecon::Trs2Lors(TVector3 dirCkov,Double_t &thetaCer,Double_t &phiCer)const
{
-// Find area inside the cerenkov ring which lays inside PCs
-// Arguments: ckovThe - cernkov
+ //Theta Cerenkov reconstruction
+ // Arguments: dirCkov photon vector in TRS
+ // Returns: thetaCer of photon in LORS
+ // phiCer of photon in LORS
+ TRotation mtheta; mtheta.RotateY(fTrkDir.Theta());
+ TRotation mphi; mphi.RotateZ(fTrkDir.Phi());
+ TRotation mrot=mphi*mtheta;
+ TVector3 dirCkovLORS;
+ dirCkovLORS=mrot*dirCkov;
+ phiCer = dirCkovLORS.Phi(); //actual value of the phi of the photon
+ thetaCer= dirCkovLORS.Theta(); //actual value of thetaCerenkov of the photon
+}
+//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+void AliHMPIDRecon::FindRingGeom(Double_t ckovAng,Int_t level)
+{
+// Find area covered in the PC acceptance
+// Arguments: ckovAng - cerenkov angle
+// level - precision in finding area and portion of ring accepted (multiple of 50)
// Returns: area of the ring in cm^2 for given theta ckov
+ Int_t kN=50*level;
+ Int_t nPoints = 0;
+ Double_t area=0;
- TVector2 pos1,pos2;
+ Bool_t first=kFALSE;
+ TVector2 pos1;
- const Int_t kN=100;
- Double_t area=0;
for(Int_t i=0;i<kN;i++){
- TracePhot(ckovAng,Double_t(TMath::TwoPi()*i /kN),pos1);//trace this photon
- TracePhot(ckovAng,Double_t(TMath::TwoPi()*(i+1)/kN),pos2);//trace this photon
- area+=(pos1-fTrkPos)*(pos2-fTrkPos);
-
+ if(!first) {
+ pos1=TracePhot(ckovAng,Double_t(TMath::TwoPi()*(i+1)/kN)); //find a good trace for the first photon
+ if(pos1.X()==-999) continue; //no area: open ring
+ if(!fParam->IsInside(pos1.X(),pos1.Y(),0)) {
+ pos1 = IntWithEdge(fMipPos,pos1); // find the very first intersection...
+ } else {
+ if(!AliHMPIDParam::IsInDead(pos1.X(),pos1.Y())) nPoints++; //photon is accepted if not in dead zone
+ }
+ first=kTRUE;
+ continue;
+ }
+ TVector2 pos2=TracePhot(ckovAng,Double_t(TMath::TwoPi()*(i+1)/kN)); //trace the next photon
+ if(pos2.X()==-999) continue; //no area: open ring
+ if(!fParam->IsInside(pos2.X(),pos2.Y(),0)) {
+ pos2 = IntWithEdge(fMipPos,pos2);
+ } else {
+ if(!AliHMPIDParam::IsInDead(pos2.X(),pos2.Y())) nPoints++; //photon is accepted if not in dead zone
+ }
+ area+=TMath::Abs((pos1-fMipPos).X()*(pos2-fMipPos).Y()-(pos1-fMipPos).Y()*(pos2-fMipPos).X()); //add area of the triangle...
+ pos1 = pos2;
}
- return area;
-}//FindRingArea()
+//--- find area and length of the ring;
+ fRingAcc = (Double_t)nPoints/(Double_t)kN;
+ area*=0.5;
+ fRingArea = area;
+}//FindRingGeom()
+//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+TVector2 AliHMPIDRecon::IntWithEdge(TVector2 p1,TVector2 p2)const
+{
+// It finds the intersection of the line for 2 points traced as photons
+// and the edge of a given PC
+// Arguments: 2 points obtained tracing the photons
+// Returns: intersection point with detector (PC) edges
+
+ Double_t xmin = (p1.X()<p2.X())? p1.X():p2.X();
+ Double_t xmax = (p1.X()<p2.X())? p2.X():p1.X();
+ Double_t ymin = (p1.Y()<p2.Y())? p1.Y():p2.Y();
+ Double_t ymax = (p1.Y()<p2.Y())? p2.Y():p1.Y();
+
+ Double_t m = TMath::Tan((p2-p1).Phi());
+ TVector2 pint;
+ //intersection with low X
+ pint.Set((Double_t)(p1.X() + (0-p1.Y())/m),0.);
+ if(pint.X()>=0 && pint.X()<=fParam->SizeAllX() &&
+ pint.X()>=xmin && pint.X()<=xmax &&
+ pint.Y()>=ymin && pint.Y()<=ymax) return pint;
+ //intersection with high X
+ pint.Set((Double_t)(p1.X() + (fParam->SizeAllY()-p1.Y())/m),(Double_t)(fParam->SizeAllY()));
+ if(pint.X()>=0 && pint.X()<=fParam->SizeAllX() &&
+ pint.X()>=xmin && pint.X()<=xmax &&
+ pint.Y()>=ymin && pint.Y()<=ymax) return pint;
+ //intersection with left Y
+ pint.Set(0.,(Double_t)(p1.Y() + m*(0-p1.X())));
+ if(pint.Y()>=0 && pint.Y()<=fParam->SizeAllY() &&
+ pint.Y()>=ymin && pint.Y()<=ymax &&
+ pint.X()>=xmin && pint.X()<=xmax) return pint;
+ //intersection with righ Y
+ pint.Set((Double_t)(fParam->SizeAllX()),(Double_t)(p1.Y() + m*(fParam->SizeAllX()-p1.X())));
+ if(pint.Y()>=0 && pint.Y()<=fParam->SizeAllY() &&
+ pint.Y()>=ymin && pint.Y()<=ymax &&
+ pint.X()>=xmin && pint.X()<=xmax) return pint;
+ return p1;
+}//IntWithEdge()
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Double_t AliHMPIDRecon::FindRingCkov(Int_t)
{
for(Int_t i=0;i<fPhotCnt;i++){//candidates loop
if(fPhotFlag[i] == 2){
- if(fPhotCkov[i]<=0) continue;//?????????????????Flag photos = 2 may imply CkovEta = 0??????????????
- if(fPhotCkov[i]<ckovMin) ckovMin=fPhotCkov[i]; //find max and min Theta ckov from all candidates within probable window
+ if(fPhotCkov[i]<ckovMin) ckovMin=fPhotCkov[i]; //find max and min Theta ckov from all candidates within probable window
if(fPhotCkov[i]>ckovMax) ckovMax=fPhotCkov[i];
- weightThetaCerenkov += fPhotCkov[i]*fPhotWei[i]; wei += fPhotWei[i]; //collect weight as sum of all candidate weghts
+ weightThetaCerenkov += fPhotCkov[i]*fPhotWei[i];
+ wei += fPhotWei[i]; //collect weight as sum of all candidate weghts
- sigma2 += 1./Sigma2(fPhotCkov[i],fPhotPhi[i]);
+ sigma2 += 1./fParam->Sigma2(fTrkDir.Theta(),fTrkDir.Phi(),fPhotCkov[i],fPhotPhi[i]);
}
}//candidates loop
if(sigma2>0) fCkovSigma2=1./sigma2;
else fCkovSigma2=1e10;
- if(wei != 0.) weightThetaCerenkov /= wei; else weightThetaCerenkov = 0.;
+ if(wei != 0.) weightThetaCerenkov /= wei; else weightThetaCerenkov = 0.;
return weightThetaCerenkov;
}//FindCkovRing()
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// Arguments: ckov- value of most probable ckov angle for track as returned by HoughResponse()
// Returns: number of photon candidates happened to be inside the window
+// Photon Flag: Flag = 0 initial set;
+// Flag = 1 good candidate (charge compatible with photon);
+// Flag = 2 photon used for the ring;
Int_t steps = (Int_t)((ckov )/ fDTheta); //how many times we need to have fDTheta to fill the distance between 0 and thetaCkovHough
Int_t iInsideCnt = 0; //count photons which Theta ckov inside the window
for(Int_t i=0;i<fPhotCnt;i++){//photon candidates loop
+ fPhotFlag[i] = 0;
if(fPhotCkov[i] >= tmin && fPhotCkov[i] <= tmax) {
fPhotFlag[i]=2;
iInsideCnt++;
return iInsideCnt;
}//FlagPhot()
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
-Double_t AliHMPIDRecon::TracePhot(Double_t ckovThe,Double_t ckovPhi,TVector2 &pos)const
+TVector2 AliHMPIDRecon::TracePhot(Double_t ckovThe,Double_t ckovPhi)const
{
// Trace a single Ckov photon from emission point somewhere in radiator up to photocathode taking into account ref indexes of materials it travereses
-// Arguments: ckovThe,ckovPhi- photon ckov angles, [rad] (warning: not photon theta and phi)
+// Arguments: ckovThe,ckovPhi- photon ckov angles in TRS, [rad]
// Returns: distance between photon point on PC and track projection
- TRotation mtheta; mtheta.RotateY(fTrkDir.Theta());
- TRotation mphi; mphi.RotateZ(fTrkDir.Phi());
- TRotation mrot=mphi*mtheta;
-
- TVector3 posCkov(fTrkPos.X(),fTrkPos.Y(),-0.5*fgkRadThick-fgkWinThick-fgkGapThick); //RAD: photon position is track position @ middle of RAD
- TVector3 dirCkov; dirCkov.SetMagThetaPhi(1,ckovThe,ckovPhi); //initially photon is directed according to requested ckov angle
- dirCkov=mrot*dirCkov; //now we know photon direction in LORS
- dirCkov.SetPhi(ckovPhi);
- if(dirCkov.Theta() > TMath::ASin(1./fgkRadIdx)) return -999;//total refraction on WIN-GAP boundary
-
- Propagate(dirCkov,posCkov,-fgkWinThick-fgkGapThick); //go to RAD-WIN boundary remeber that z=0 is PC plane
- Refract (dirCkov, fgkRadIdx,fgkWinIdx ); //RAD-WIN refraction
- Propagate(dirCkov,posCkov,-fgkGapThick ); //go to WIN-GAP boundary
- Refract (dirCkov, fgkWinIdx,fgkGapIdx ); //WIN-GAP refraction
- Propagate(dirCkov,posCkov,0 ); //go to PC
- pos.Set(posCkov.X(),posCkov.Y());
- return (pos-fTrkPos).Mod();
-}//TracePhoton()
+ Double_t theta,phi;
+ TVector3 dirTRS,dirLORS;
+ dirTRS.SetMagThetaPhi(1,ckovThe,ckovPhi); //photon in TRS
+ Trs2Lors(dirTRS,theta,phi);
+ dirLORS.SetMagThetaPhi(1,theta,phi); //photon in LORS
+ return TraceForward(dirLORS); //now foward tracing
+}//TracePhot()
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
-void AliHMPIDRecon::Propagate(const TVector3 &dir,TVector3 &pos,Double_t z)const
+void AliHMPIDRecon::Propagate(const TVector3 dir,TVector3 &pos,Double_t z)const
{
// Finds an intersection point between a line and XY plane shifted along Z.
// Arguments: dir,pos - vector along the line and any point of the line
// Returns: none
// On exit: dir is new direction
Double_t sinref=(n1/n2)*TMath::Sin(dir.Theta());
- if(sinref>1.) dir.SetXYZ(-999,-999,-999);
+ if(TMath::Abs(sinref)>1.) dir.SetXYZ(-999,-999,-999);
else dir.SetTheta(TMath::ASin(sinref));
}//Refract()
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Double_t AliHMPIDRecon::HoughResponse()
{
//
-//
+// fIdxMip = mipId;
+
//
Double_t kThetaMax=0.75;
Int_t nChannels = (Int_t)(kThetaMax/fDTheta+0.5);
Int_t bin = (Int_t)(0.5+angle/(fDTheta));
Double_t weight=1.;
if(fIsWEIGHT){
- Double_t lowerlimit = ((Double_t)bin)*fDTheta - 0.5*fDTheta; Double_t upperlimit = ((Double_t)bin)*fDTheta + 0.5*fDTheta;
- Double_t diffArea = FindRingArea(upperlimit)-FindRingArea(lowerlimit);
+ Double_t lowerlimit = ((Double_t)bin)*fDTheta - 0.5*fDTheta; Double_t upperlimit = ((Double_t)bin)*fDTheta + 0.5*fDTheta;
+ FindRingGeom(lowerlimit);
+ Double_t areaLow = GetRingArea();
+ FindRingGeom(upperlimit);
+ Double_t areaHigh = GetRingArea();
+ Double_t diffArea = areaHigh - areaLow;
if(diffArea>0) weight = 1./diffArea;
}
photsw->Fill(angle,weight);
// evaluate the "BEST" theta ckov as the maximum value of histogramm
Double_t *pVec = resultw->GetArray();
Int_t locMax = TMath::LocMax(nBin,pVec);
- phots->Delete();photsw->Delete();resultw->Delete(); // Reset and delete objects
+ delete phots;delete photsw;delete resultw; // Reset and delete objects
return (Double_t)(locMax*fDTheta+0.5*fDTheta); //final most probable track theta ckov
}//HoughResponse()
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
-Double_t AliHMPIDRecon::Sigma2(Double_t ckovTh, Double_t ckovPh)const
-{
-// Analithical calculation of total error (as a sum of localization, geometrical and chromatic errors) on Cerenkov angle for a given Cerenkov photon
-// created by a given MIP. Fromulae according to CERN-EP-2000-058
-// Arguments: Cerenkov and azimuthal angles for Cerenkov photon, [radians]
-// dip and azimuthal angles for MIP taken at the entrance to radiator, [radians]
-// MIP beta
-// Returns: absolute error on Cerenkov angle, [radians]
-
- TVector3 v(-999,-999,-999);
- Double_t trkBeta = 1./(TMath::Cos(ckovTh)*fgkRadIdx);
-
- v.SetX(SigLoc (ckovTh,ckovPh,trkBeta));
- v.SetY(SigGeom(ckovTh,ckovPh,trkBeta));
- v.SetZ(SigCrom(ckovTh,ckovPh,trkBeta));
-
- return v.Mag2();
-}
-//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
-Double_t AliHMPIDRecon::SigLoc(Double_t thetaC, Double_t phiC,Double_t betaM)const
-{
-// Analithical calculation of localization error (due to finite segmentation of PC) on Cerenkov angle for a given Cerenkov photon
-// created by a given MIP. Fromulae according to CERN-EP-2000-058
-// Arguments: Cerenkov and azimuthal angles for Cerenkov photon, [radians]
-// dip and azimuthal angles for MIP taken at the entrance to radiator, [radians]
-// MIP beta
-// Returns: absolute error on Cerenkov angle, [radians]
- Double_t phiDelta = phiC - fTrkDir.Phi();
-
- Double_t alpha =TMath::Cos(fTrkDir.Theta())-TMath::Tan(thetaC)*TMath::Cos(phiDelta)*TMath::Sin(fTrkDir.Theta());
- Double_t k = 1.-fgkRadIdx*fgkRadIdx+alpha*alpha/(betaM*betaM);
- if (k<0) return 1e10;
-
- Double_t mu =TMath::Sin(fTrkDir.Theta())*TMath::Sin(fTrkDir.Phi())+TMath::Tan(thetaC)*(TMath::Cos(fTrkDir.Theta())*TMath::Cos(phiDelta)*TMath::Sin(fTrkDir.Phi())+TMath::Sin(phiDelta)*TMath::Cos(fTrkDir.Phi()));
- Double_t e =TMath::Sin(fTrkDir.Theta())*TMath::Cos(fTrkDir.Phi())+TMath::Tan(thetaC)*(TMath::Cos(fTrkDir.Theta())*TMath::Cos(phiDelta)*TMath::Cos(fTrkDir.Phi())-TMath::Sin(phiDelta)*TMath::Sin(fTrkDir.Phi()));
-
- Double_t kk = betaM*TMath::Sqrt(k)/(8*alpha);
- Double_t dtdxc = kk*(k*(TMath::Cos(phiDelta)*TMath::Cos(fTrkDir.Phi())-TMath::Cos(fTrkDir.Theta())*TMath::Sin(phiDelta)*TMath::Sin(fTrkDir.Phi()))-(alpha*mu/(betaM*betaM))*TMath::Sin(fTrkDir.Theta())*TMath::Sin(phiDelta));
- Double_t dtdyc = kk*(k*(TMath::Cos(phiDelta)*TMath::Sin(fTrkDir.Phi())+TMath::Cos(fTrkDir.Theta())*TMath::Sin(phiDelta)*TMath::Cos(fTrkDir.Phi()))+(alpha* e/(betaM*betaM))*TMath::Sin(fTrkDir.Theta())*TMath::Sin(phiDelta));
-
- return TMath::Sqrt(0.2*0.2*dtdxc*dtdxc + 0.25*0.25*dtdyc*dtdyc);
-}
-//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
-Double_t AliHMPIDRecon::SigCrom(Double_t thetaC, Double_t phiC,Double_t betaM)const
-{
-// Analithical calculation of chromatic error (due to lack of knowledge of Cerenkov photon energy) on Cerenkov angle for a given Cerenkov photon
-// created by a given MIP. Fromulae according to CERN-EP-2000-058
-// Arguments: Cerenkov and azimuthal angles for Cerenkov photon, [radians]
-// dip and azimuthal angles for MIP taken at the entrance to radiator, [radians]
-// MIP beta
-// Returns: absolute error on Cerenkov angle, [radians]
- Double_t phiDelta = phiC - fTrkDir.Phi();
- Double_t alpha =TMath::Cos(fTrkDir.Theta())-TMath::Tan(thetaC)*TMath::Cos(phiDelta)*TMath::Sin(fTrkDir.Theta());
-
- Double_t dtdn = TMath::Cos(fTrkDir.Theta())*fgkRadIdx*betaM*betaM/(alpha*TMath::Tan(thetaC));
-
- Double_t f = 0.00928*(7.75-5.635)/TMath::Sqrt(12.);
-
- return f*dtdn;
-}//SigCrom()
-//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
-Double_t AliHMPIDRecon::SigGeom(Double_t thetaC, Double_t phiC,Double_t betaM)const
-{
-// Analithical calculation of geometric error (due to lack of knowledge of creation point in radiator) on Cerenkov angle for a given Cerenkov photon
-// created by a given MIP. Formulae according to CERN-EP-2000-058
-// Arguments: Cerenkov and azimuthal angles for Cerenkov photon, [radians]
-// dip and azimuthal angles for MIP taken at the entrance to radiator, [radians]
-// MIP beta
-// Returns: absolute error on Cerenkov angle, [radians]
-
- Double_t phiDelta = phiC - fTrkDir.Phi();
- Double_t alpha =TMath::Cos(fTrkDir.Theta())-TMath::Tan(thetaC)*TMath::Cos(phiDelta)*TMath::Sin(fTrkDir.Theta());
-
- Double_t k = 1.-fgkRadIdx*fgkRadIdx+alpha*alpha/(betaM*betaM);
- if (k<0) return 1e10;
-
- Double_t eTr = 0.5*1.5*betaM*TMath::Sqrt(k)/(8*alpha);
- Double_t lambda = 1.-TMath::Sin(fTrkDir.Theta())*TMath::Sin(fTrkDir.Theta())*TMath::Sin(phiC)*TMath::Sin(phiC);
-
- Double_t c = 1./(1.+ eTr*k/(alpha*alpha*TMath::Cos(thetaC)*TMath::Cos(thetaC)));
- Double_t i = betaM*TMath::Tan(thetaC)*lambda*TMath::Power(k,1.5);
- Double_t ii = 1.+eTr*betaM*i;
-
- Double_t err = c * (i/(alpha*alpha*8) + ii*(1.-lambda) / ( alpha*alpha*8*betaM*(1.+eTr)) );
- Double_t trErr = 1.5/(TMath::Sqrt(12.)*TMath::Cos(fTrkDir.Theta()));
-
- return trErr*err;
-}//SigGeom()
-//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++