**************************************************************************/
#include "AliITSVertexerZ.h"
#include<TBranch.h>
+#include<TClonesArray.h>
+#include<TFile.h>
#include<TH1.h>
#include <TString.h>
#include<TTree.h>
#include "AliITSgeom.h"
#include "AliITSDetTypeRec.h"
#include "AliITSRecPoint.h"
+#include "AliITSZPoint.h"
+#include "AliHeader.h"
+#include "AliGenEventHeader.h"
/////////////////////////////////////////////////////////////////
// this class implements a fast method to determine
fZFound(0),
fZsig(0.),
fZCombc(0),
-fZCombv(0),
-fZCombf(0),
fLowLim(0.),
fHighLim(0.),
fStepCoarse(0),
-fStepFine(0),
fTolerance(0.),
-fMaxIter(0){
+fMaxIter(0),
+fWindowWidth(0) {
// Default constructor
- SetDiffPhiMax(0);
- SetFirstLayerModules(0);
- SetSecondLayerModules(0);
- SetLowLimit(0.);
- SetHighLimit(0.);
- SetBinWidthCoarse(0.);
- SetBinWidthFine(0.);
- SetTolerance(0.);
- SetPPsetting(0.,0.);
+ SetDiffPhiMax();
+ SetFirstLayerModules();
+ SetSecondLayerModules();
+ SetLowLimit();
+ SetHighLimit();
+ SetBinWidthCoarse();
+ SetTolerance();
+ SetPPsetting();
ConfigIterations();
+ SetWindowWidth();
}
//______________________________________________________________________
fZFound(0),
fZsig(0.),
fZCombc(0),
-fZCombv(0),
-fZCombf(0),
fLowLim(0.),
fHighLim(0.),
fStepCoarse(0),
-fStepFine(0),
fTolerance(0.),
-fMaxIter(0) {
+fMaxIter(0),
+fWindowWidth(0) {
// Standard Constructor
SetDiffPhiMax();
SetFirstLayerModules();
SetLowLimit();
SetHighLimit();
SetBinWidthCoarse();
- SetBinWidthFine();
SetTolerance();
SetPPsetting();
ConfigIterations();
+ SetWindowWidth();
}
fZFound(vtxr.fZFound),
fZsig(vtxr.fZsig),
fZCombc(vtxr.fZCombc),
-fZCombv(vtxr.fZCombv),
-fZCombf(vtxr.fZCombf),
fLowLim(vtxr.fLowLim),
fHighLim(vtxr.fHighLim),
fStepCoarse(vtxr.fStepCoarse),
-fStepFine(vtxr.fStepFine),
fTolerance(vtxr.fTolerance),
-fMaxIter(vtxr.fMaxIter) {
+fMaxIter(vtxr.fMaxIter),
+fWindowWidth(vtxr.fWindowWidth){
// Copy constructor
}
AliITSVertexerZ::~AliITSVertexerZ() {
// Destructor
delete fZCombc;
- delete fZCombf;
- delete fZCombv;
}
//______________________________________________________________________
if(ptr)for(Int_t j=0;j<fMaxIter;j++)fPhiDiffIter[j]=ptr[j];
}
+//______________________________________________________________________
+Int_t AliITSVertexerZ::GetPeakRegion(TH1F*h, Int_t &binmin, Int_t &binmax) const {
+ // Finds a region around a peak in the Z histogram
+ // Case of 2 peaks is treated
+ Int_t imax=h->GetNbinsX();
+ Float_t maxval=0;
+ Int_t bi1=h->GetMaximumBin();
+ Int_t bi2=0;
+ for(Int_t i=imax;i>=1;i--){
+ if(h->GetBinContent(i)>maxval){
+ maxval=h->GetBinContent(i);
+ bi2=i;
+ }
+ }
+ Int_t npeaks=0;
+
+ if(bi1==bi2){
+ binmin=bi1-3;
+ binmax=bi1+3;
+ npeaks=1;
+ }else{
+ TH1F *copy = new TH1F(*h);
+ copy->SetBinContent(bi1,0.);
+ copy->SetBinContent(bi2,0.);
+ Int_t l1=TMath::Max(bi1-3,1);
+ Int_t l2=TMath::Min(bi1+3,h->GetNbinsX());
+ Float_t cont1=copy->Integral(l1,l2);
+ Int_t ll1=TMath::Max(bi2-3,1);
+ Int_t ll2=TMath::Min(bi2+3,h->GetNbinsX());
+ Float_t cont2=copy->Integral(ll1,ll2);
+ if(cont1>cont2){
+ binmin=l1;
+ binmax=l2;
+ npeaks=1;
+ }
+ if(cont2>cont1){
+ binmin=ll1;
+ binmax=ll2;
+ npeaks=1;
+ }
+ if(cont1==cont2){
+ binmin=l1;
+ binmax=ll2;
+ if(bi2-bi1==1) npeaks=1;
+ else npeaks=2;
+ }
+ delete copy;
+ }
+ return npeaks;
+}
//______________________________________________________________________
AliESDVertex* AliITSVertexerZ::FindVertexForCurrentEvent(Int_t evnumber){
// Defines the AliESDVertex for the current event
// This loop counts the number of recpoints on layer1 (central modules)
for(Int_t module= fFirstL1; module<=fLastL1;module++){
// Keep only central modules
- if(module%4==0 || module%4==3)continue;
+ // if(module%4==0 || module%4==3)continue;
// cout<<"Procesing module "<<module<<" ";
branch->GetEvent(module);
// cout<<"Number of clusters "<<clusters->GetEntries()<<endl;
Float_t *yc1 = new Float_t [nrpL1];
Float_t *zc1 = new Float_t [nrpL1];
Float_t *phi1 = new Float_t [nrpL1];
+ Float_t *err1 = new Float_t [nrpL1];
Float_t *xc2 = new Float_t [nrpL2]; // coordinates of the L1 Recpoints
Float_t *yc2 = new Float_t [nrpL2];
Float_t *zc2 = new Float_t [nrpL2];
Float_t *phi2 = new Float_t [nrpL2];
+ Float_t *err2 = new Float_t [nrpL2];
Int_t ind = 0;// running index for RP
// Force a coarse bin size of 200 microns if the number of clusters on layer 2
// is low
if(nrpL2<fPPsetting[0])SetBinWidthCoarse(fPPsetting[1]);
- // By default nbinfine = (10+10)/0.0005=40000
- Int_t nbinfine = static_cast<Int_t>((fHighLim-fLowLim)/fStepFine);
// By default nbincoarse=(10+10)/0.01=2000
Int_t nbincoarse = static_cast<Int_t>((fHighLim-fLowLim)/fStepCoarse);
- // Set stepverycoarse = 3*fStepCoarse
- Int_t nbinvcoarse = static_cast<Int_t>((fHighLim-fLowLim)/(3.*fStepCoarse));
if(fZCombc)delete fZCombc;
fZCombc = new TH1F("fZCombc","Z",nbincoarse,fLowLim,fLowLim+nbincoarse*fStepCoarse);
- if(fZCombv)delete fZCombv;
- fZCombv = new TH1F("fZCombv","Z",nbinvcoarse,fLowLim,fLowLim+nbinvcoarse*3.*fStepCoarse);
- if(fZCombf)delete fZCombf;
- fZCombf = new TH1F("fZCombf","Z",nbinfine,fLowLim,fLowLim+nbinfine*fStepFine);
- // Loop on modules of layer 1 (restricted to central modules)
+
+ // Loop on modules of layer 1
+
for(Int_t module= fFirstL1; module<=fLastL1;module++){
- if(module%4==0 || module%4==3)continue;
+ // if(module%4==0 || module%4==3)continue;
branch->GetEvent(module);
Int_t nrecp1 = itsRec->GetEntries();
for(Int_t j=0;j<nrecp1;j++){
// azimuthal angle is computed in the interval 0 --> 2*pi
phi1[ind] = TMath::ATan2(gc[1],gc[0]);
if(phi1[ind]<0)phi1[ind]=2*TMath::Pi()+phi1[ind];
+ err1[ind]=recp->GetSigmaZ2();
ind++;
}
detTypeRec.ResetRecPoints();
zc2[ind]=gc[2];
phi2[ind] = TMath::ATan2(gc[1],gc[0]);
if(phi2[ind]<0)phi2[ind]=2*TMath::Pi()+phi2[ind];
+ err2[ind]=recp->GetSigmaZ2();
ind++;
}
detTypeRec.ResetRecPoints();
}
- // Int_t nolines=0;
+/* Test the ffect of mutiple scatternig on error. Negligible
+ // Multiple scattering
+ Float_t beta=1.,pmed=0.875; //pmed=875 MeV (for tracks with dphi<0.01 rad)
+ Float_t beta2=beta*beta;
+ Float_t p2=pmed*pmed;
+ Float_t rBP=3; //Beam Pipe radius = 3cm
+ Float_t dBP=0.08/35.3; // 800 um of Be
+ Float_t dL1=0.01; //approx. 1% of radiation length
+ Float_t theta2BP=14.1*14.1/(beta2*p2*1e6)*TMath::Abs(dBP);
+ Float_t theta2L1=14.1*14.1/(beta2*p2*1e6)*TMath::Abs(dL1);
+*/
+ TClonesArray *points = new TClonesArray("AliITSZPoint",nrpL1*nrpL2);
+ TClonesArray &pts = *points;
+ Int_t nopoints =0;
for(Int_t i=0;i<nrpL1;i++){ // loop on L1 RP
Float_t r1=TMath::Sqrt(xc1[i]*xc1[i]+yc1[i]*yc1[i]); // radius L1 RP
for(Int_t j=0;j<nrpL2;j++){ // loop on L2 RP
if(diff>TMath::Pi())diff=2.*TMath::Pi()-diff; //diff<pi
if(diff<fDiffPhiMax){ // cut on 10 milliradians by def.
Float_t r2=TMath::Sqrt(xc2[j]*xc2[j]+yc2[j]*yc2[j]); // radius L2 RP
+// Float_t tgth=(zc2[j]-zc1[i])/(r2-r1); // slope
Float_t zr0=(r2*zc1[i]-r1*zc2[j])/(r2-r1); //Z @ null radius
- fZCombf->Fill(zr0);
+ Float_t ezr0q=(r2*r2*err1[i]+r1*r1*err2[j])/(r2-r1)/(r2-r1); //error on Z @ null radius
+ /*
+ ezr0q+=r1*r1*(1+tgth*tgth)*theta2L1/2; // multiple scattering in layer 1
+ ezr0q+=rBP*rBP*(1+tgth*tgth)*theta2BP/2; // multiple scattering in beam pipe
+ */
+ new(pts[nopoints++])AliITSZPoint(zr0,ezr0q);
+
fZCombc->Fill(zr0);
- fZCombv->Fill(zr0);
- Double_t pA[3];
- Double_t pB[3];
- pA[0]=xc1[i];
- pA[1]=yc1[i];
- pA[2]=zc1[i];
- pB[0]=xc2[j];
- pB[1]=yc2[j];
- pB[2]=zc2[j];
- // MakeTracklet(pA,pB,nolines);
}
}
}
delete [] yc1;
delete [] zc1;
delete [] phi1;
+ delete [] err1;
delete [] xc2;
delete [] yc2;
delete [] zc2;
delete [] phi2;
+ delete [] err2;
+
+ points->Sort();
+
Double_t contents = fZCombc->GetEntries()- fZCombc->GetBinContent(0)-fZCombc->GetBinContent(nbincoarse+1);
if(contents<1.){
// Warning("FindVertexForCurrentEvent","Insufficient number of rec. points\n");
fCurrentVertex = new AliESDVertex(0.,5.3,-1);
return;
}
- /*
- else {
- if(fDebug>0)cout<<"Number of entries in hist. "<<fZCombc->GetEntries()<<endl;
- }
- */
TH1F *hc = fZCombc;
- Bool_t goon = kFALSE;
- Int_t cnt = 0;
- Int_t bi;
-
- do {
- goon = kFALSE;
- cnt++;
- bi = hc->GetMaximumBin(); // bin with maximal content on coarse histogram
- if(hc->GetBinContent(bi)<3){
- if(cnt==1)goon = kTRUE;
- hc = fZCombv;
- }
- } while(goon);
-
- Float_t centre = hc->GetBinCenter(bi); // z value of the bin with maximal content
- Int_t bifine=static_cast<Int_t>((hc->GetBinCenter(bi)-fZCombf->GetBinLowEdge(0))/fStepFine);
- Int_t nbinsfine=static_cast<Int_t>(3*hc->GetBinWidth(bi)/fStepFine);
- // evaluation of the centroid
- Int_t ii1=TMath::Max(bifine-nbinsfine,1);
- Int_t ii2=TMath::Min(bifine+nbinsfine,fZCombf->GetNbinsX());
- centre = 0.;
- Int_t nn=0;
- for(Int_t ii=ii1;ii<ii2;ii++){
- centre+= fZCombf->GetBinCenter(ii)*fZCombf->GetBinContent(ii);
- nn+=static_cast<Int_t>(fZCombf->GetBinContent(ii));
- }
- if (nn) centre/=nn;
- /*
- if(fDebug>0){
- cout<<"Value of center "<<centre<<endl;
- cout<<"Population of 3 central bins: "<<hc->GetBinContent(bi-1)<<", ";
- cout<<hc->GetBinContent(bi)<<", ";
- cout<<hc->GetBinContent(bi+1)<<endl;
+ if(hc->GetBinContent(hc->GetMaximumBin())<3)hc->Rebin(3);
+ Int_t binmin,binmax;
+ Int_t nPeaks=GetPeakRegion(hc,binmin,binmax);
+ if(nPeaks==2)AliWarning("2 peaks found");
+ Float_t zm =0.;
+ Float_t ezm =0.;
+ Float_t lim1 = hc->GetBinLowEdge(binmin);
+ Float_t lim2 = hc->GetBinLowEdge(binmax)+hc->GetBinWidth(binmax);
+
+ if(nPeaks ==1 && (lim2-lim1)<fWindowWidth){
+ Float_t c=(lim1+lim2)/2.;
+ lim1=c-fWindowWidth/2.;
+ lim2=c+fWindowWidth/2.;
}
- */
- // n1 is the bin number of fine histogram containing the point located 1 coarse bin less than "centre"
- Int_t n1 = static_cast<Int_t>((centre-hc->GetBinWidth(bi)-fZCombf->GetBinLowEdge(0))/fStepFine);
- // n2 is the bin number of fine histogram containing the point located 1 coarse bin more than "centre"
- Int_t n2 = static_cast<Int_t>((centre+hc->GetBinWidth(bi)-fZCombf->GetBinLowEdge(0))/fStepFine);
- if(n1<1)n1=1;
- if(n2>nbinfine)n2=nbinfine;
- Int_t niter = 0;
- goon = kTRUE;
- Int_t num=0;
- Bool_t last = kFALSE;
-
- while(goon || last){
- fZFound = 0.;
- fZsig = 0.;
- num=0;
- // at the end of the loop:
- // fZFound = N*(Average Z) - where N is the number of tracklets
- // num=N
- // fZsig = N*Q - where Q is the average of Z*Z
- for(Int_t n=n1;n<=n2;n++){
- fZFound+=fZCombf->GetBinCenter(n)*fZCombf->GetBinContent(n);
- num+=static_cast<Int_t>(fZCombf->GetBinContent(n));
- fZsig+=fZCombf->GetBinCenter(n)*fZCombf->GetBinCenter(n)*fZCombf->GetBinContent(n);
- }
- if(num<2){
- fZsig = 5.3; // Default error from the beam sigmoid
- }
- else{
- Float_t radi = fZsig/(num-1)-fZFound*fZFound/num/(num-1);
- // radi = square root of sample variance of Z
- if(radi>0.)fZsig=TMath::Sqrt(radi);
- else fZsig=5.3; // Default error from the beam sigmoid
- // fZfound - Average Z
- fZFound/=num;
+ Int_t niter = 0, ncontr=0;
+ do {
+ // symmetrization
+ if(zm !=0.){
+ Float_t semilarg=TMath::Min((lim2-zm),(zm-lim1));
+ lim1=zm - semilarg;
+ lim2=zm + semilarg;
}
- if(!last){
- // goon is true if the distance between the found Z and the lower bin differs from the distance between the found Z and
- // the upper bin by more than tolerance (0.002)
- goon = TMath::Abs(TMath::Abs(fZFound-fZCombf->GetBinCenter(n1))-TMath::Abs(fZFound-fZCombf->GetBinCenter(n2)))>fTolerance;
- // a window in the fine grained histogram is centered aroung the found Z. The width is 2 bins of
- // the coarse grained histogram
- if(num>0){
- n1 = static_cast<Int_t>((fZFound-hc->GetBinWidth(bi)-fZCombf->GetBinLowEdge(0))/fStepFine);
- if(n1<1)n1=1;
- n2 = static_cast<Int_t>((fZFound+hc->GetBinWidth(bi)-fZCombf->GetBinLowEdge(0))/fStepFine);
- if(n2>nbinfine)n2=nbinfine;
- /*
- if(fDebug>0){
- cout<<"Search restricted to n1 = "<<n1<<", n2= "<<n2<<endl;
- cout<<"z1= "<<fZCombf->GetBinCenter(n1)<<", n2 = "<<fZCombf->GetBinCenter(n2)<<endl;
- }
- */
- }
- else {
- n1 = static_cast<Int_t>((centre-(niter+2)*hc->GetBinWidth(bi)-fZCombf->GetBinLowEdge(0))/fStepFine);
- n2 = static_cast<Int_t>((centre+(niter+2)*hc->GetBinWidth(bi)-fZCombf->GetBinLowEdge(0))/fStepFine);
- if(n1<1)n1=1;
- if(n2>nbinfine)n2=nbinfine;
- }
- niter++;
- // no more than 10 adjusting iterations
- if(niter>=10){
- goon = kFALSE;
- // Warning("FindVertexForCurrentEvent","The procedure does not converge\n");
- }
- if((fZsig> 0.0001) && !goon && num>5){
- last = kTRUE;
- n1 = static_cast<Int_t>((fZFound-fZsig-fZCombf->GetBinLowEdge(0))/fZCombf->GetBinWidth(0));
- if(n1<1)n1=1;
- n2 = static_cast<Int_t>((fZFound+fZsig-fZCombf->GetBinLowEdge(0))/fZCombf->GetBinWidth(0));
- if(n2>nbinfine)n2=nbinfine;
- /*
- if(fDebug>0){
- cout<<"FINAL Search restricted to n1 = "<<n1<<", n2= "<<n2<<endl;
- cout<<"z1= "<<fZCombf->GetBinCenter(n1)<<", n2 = "<<fZCombf->GetBinCenter(n2)<<endl;
- }
- */
+ zm=0.;
+ ezm=0.;
+ ncontr=0;
+ for(Int_t i =0; i<points->GetEntriesFast(); i++){
+ AliITSZPoint* p=(AliITSZPoint*)points->UncheckedAt(i);
+ if(p->GetZ()>lim1 && p->GetZ()<lim2){
+ Float_t deno = p->GetErrZ();
+ zm+=p->GetZ()/deno;
+ ezm+=1./deno;
+ ncontr++;
}
}
- else {
- last = kFALSE;
- }
-
- }
- // if(fDebug>0)cout<<"Numer of Iterations "<<niter<<endl<<endl;
- // if(num!=0)fZsig/=TMath::Sqrt(num);
- if (fZsig<=0) fZsig=5.3; // Default error from the beam sigmoid
- fCurrentVertex = new AliESDVertex(fZFound,fZsig,num);
+ zm/=ezm;
+ ezm=TMath::Sqrt(1./ezm);
+ niter++;
+ } while(niter<10 && TMath::Abs((zm-lim1)-(lim2-zm))>fTolerance);
+ fCurrentVertex = new AliESDVertex(zm,ezm,ncontr);
fCurrentVertex->SetTitle("vertexer: B");
ResetHistograms();
itsLoader->UnloadRecPoints();
void AliITSVertexerZ::ResetHistograms(){
// delete TH1 data members
if(fZCombc)delete fZCombc;
- if(fZCombf)delete fZCombf;
- if(fZCombv)delete fZCombv;
fZCombc = 0;
- fZCombf = 0;
- fZCombv = 0;
}
//______________________________________________________________________
if(fCurrentVertex){
WriteCurrentVertex();
}
- /*
- else {
- if(fDebug>0){
- cout<<"Vertex not found for event "<<i<<endl;
- cout<<"fZFound = "<<fZFound<<", fZsig= "<<fZsig<<endl;
- }
- }
- */
}
}
cout <<fLastL2<<endl;
cout <<" Max Phi difference: "<<fDiffPhiMax<<endl;
cout <<"Limits for Z histograms: "<<fLowLim<<"; "<<fHighLim<<endl;
- cout <<"Bin sizes for coarse and fine z histos "<<fStepCoarse<<"; "<<fStepFine<<endl;
+ cout <<"Bin sizes for coarse z histos "<<fStepCoarse<<endl;
cout <<" Current Z "<<fZFound<<"; Z sig "<<fZsig<<endl;
cout <<" Debug flag: "<<fDebug<<endl;
cout <<"First event to be processed "<<fFirstEvent;
else{
cout<<"fZCombc does not exist\n";
}
- if(fZCombv){
- cout<<"fZCombv exists - entries="<<fZCombv->GetEntries()<<endl;
- }
- else{
- cout<<"fZCombv does not exist\n";
- }
- if(fZCombf){
- cout<<"fZCombf exists - entries="<<fZCombv->GetEntries()<<endl;
- }
- else{
- cout<<"fZCombf does not exist\n";
- }
cout <<"=======================================================\n";
}