//-------------------------------------------------------------------------
#include <TClass.h>
#include <TMath.h>
+#include <TH1F.h>
+#include <TGeoManager.h>
+#include "AliMagF.h"
#include "AliTracker.h"
+#include "AliGeomManager.h"
#include "AliCluster.h"
#include "AliKalmanTrack.h"
+extern TGeoManager *gGeoManager;
+
Bool_t AliTracker::fgUniformField=kTRUE;
-Double_t AliTracker::fgBz=0.;
+Double_t AliTracker::fgBz=kAlmost0Field;
const AliMagF *AliTracker::fgkFieldMap=0;
+Bool_t AliTracker::fFillResiduals=kFALSE;
+TObjArray *AliTracker::fResiduals=0;
ClassImp(AliTracker)
AliTracker::AliTracker():
+ TObject(),
fX(0),
fY(0),
fZ(0),
if (!fgkFieldMap) AliWarning("Field map is not set. Call AliTracker::SetFieldMap before creating a tracker!");
}
+//__________________________________________________________________________
+AliTracker::AliTracker(const AliTracker &atr):
+ TObject(atr),
+ fX(atr.fX),
+ fY(atr.fY),
+ fZ(atr.fZ),
+ fSigmaX(atr.fSigmaX),
+ fSigmaY(atr.fSigmaY),
+ fSigmaZ(atr.fSigmaZ)
+{
+ //--------------------------------------------------------------------
+ // The default constructor.
+ //--------------------------------------------------------------------
+ if (!fgkFieldMap) AliWarning("Field map is not set. Call AliTracker::SetFieldMap before creating a tracker!");
+}
+
+//__________________________________________________________________________
void AliTracker::SetFieldMap(const AliMagF* map, Bool_t uni) {
//--------------------------------------------------------------------
//This passes the field map to the reconstruction.
//Double_t bz=-b[2];
Double_t bz=-map->SolenoidField();
- fgBz=TMath::Sign(1e-13,bz) + bz;
+ fgBz=TMath::Sign(kAlmost0Field,bz) + bz;
+
+}
+
+//__________________________________________________________________________
+void AliTracker::FillClusterArray(TObjArray* /*array*/) const
+{
+ // Publishes all pointers to clusters known to the tracker into the
+ // passed object array.
+ // The ownership is not transfered - the caller is not expected to delete
+ // the clusters.
+ AliWarning("should be overriden by a sub-class.");
}
//__________________________________________________________________________
//This function "cooks" a track label. If label<0, this track is fake.
//--------------------------------------------------------------------
Int_t noc=t->GetNumberOfClusters();
+ if (noc<1) return;
Int_t *lb=new Int_t[noc];
Int_t *mx=new Int_t[noc];
AliCluster **clusters=new AliCluster*[noc];
c->Use();
}
}
+
+Double_t AliTracker::GetBz(Float_t *r) {
+ //------------------------------------------------------------------
+ // Returns Bz (kG) at the point "r" .
+ //------------------------------------------------------------------
+ Float_t b[3]; fgkFieldMap->Field(r,b);
+ Double_t bz=-Double_t(b[2]);
+ return (TMath::Sign(kAlmost0Field,bz) + bz);
+}
+
+Double_t
+AliTracker::MeanMaterialBudget(Double_t *start,Double_t *end,Double_t *mparam)
+{
+ //
+ // Calculate mean material budget and material properties between
+ // the points "start" and "end".
+ //
+ // "mparam" - parameters used for the energy and multiple scattering
+ // corrections:
+ //
+ // mparam[0] - mean density: sum(x_i*rho_i)/sum(x_i) [g/cm3]
+ // mparam[1] - equivalent rad length fraction: sum(x_i/X0_i) [adimensional]
+ // mparam[2] - mean A: sum(x_i*A_i)/sum(x_i) [adimensional]
+ // mparam[3] - mean Z: sum(x_i*Z_i)/sum(x_i) [adimensional]
+ // mparam[4] - length: sum(x_i) [cm]
+ // mparam[5] - Z/A mean: sum(x_i*Z_i/A_i)/sum(x_i) [adimensional]
+ // mparam[6] - number of boundary crosses
+ //
+ // Origin: Marian Ivanov, Marian.Ivanov@cern.ch
+ //
+ // Corrections and improvements by
+ // Andrea Dainese, Andrea.Dainese@lnl.infn.it,
+ // Andrei Gheata, Andrei.Gheata@cern.ch
+ //
+
+ mparam[0]=0; mparam[1]=1; mparam[2] =0; mparam[3] =0;
+ mparam[4]=0; mparam[5]=0; mparam[6]=0;
+ //
+ Double_t bparam[6]; // total parameters
+ Double_t lparam[6]; // local parameters
+
+ for (Int_t i=0;i<6;i++) bparam[i]=0;
+
+ if (!gGeoManager) {
+ printf("ERROR: no TGeo\n");
+ return 0.;
+ }
+ //
+ Double_t length;
+ Double_t dir[3];
+ length = TMath::Sqrt((end[0]-start[0])*(end[0]-start[0])+
+ (end[1]-start[1])*(end[1]-start[1])+
+ (end[2]-start[2])*(end[2]-start[2]));
+ mparam[4]=length;
+ if (length<TGeoShape::Tolerance()) return 0.0;
+ Double_t invlen = 1./length;
+ dir[0] = (end[0]-start[0])*invlen;
+ dir[1] = (end[1]-start[1])*invlen;
+ dir[2] = (end[2]-start[2])*invlen;
+
+ // Initialize start point and direction
+ TGeoNode *currentnode = 0;
+ TGeoNode *startnode = gGeoManager->InitTrack(start, dir);
+ //printf("%s length=%f\n",gGeoManager->GetPath(),length);
+ if (!startnode) {
+ AliErrorClass(Form("start point out of geometry: x %f, y %f, z %f",
+ start[0],start[1],start[2]));
+ return 0.0;
+ }
+ TGeoMaterial *material = startnode->GetVolume()->GetMedium()->GetMaterial();
+ lparam[0] = material->GetDensity();
+ lparam[1] = material->GetRadLen();
+ lparam[2] = material->GetA();
+ lparam[3] = material->GetZ();
+ lparam[4] = length;
+ lparam[5] = lparam[3]/lparam[2];
+ if (material->IsMixture()) {
+ TGeoMixture * mixture = (TGeoMixture*)material;
+ lparam[5] =0;
+ Double_t sum =0;
+ for (Int_t iel=0;iel<mixture->GetNelements();iel++){
+ sum += mixture->GetWmixt()[iel];
+ lparam[5]+= mixture->GetZmixt()[iel]*mixture->GetWmixt()[iel]/mixture->GetAmixt()[iel];
+ }
+ lparam[5]/=sum;
+ }
+
+ // Locate next boundary within length without computing safety.
+ // Propagate either with length (if no boundary found) or just cross boundary
+ gGeoManager->FindNextBoundaryAndStep(length, kFALSE);
+ Double_t step = 0.0; // Step made
+ Double_t snext = gGeoManager->GetStep();
+ // If no boundary within proposed length, return current density
+ if (!gGeoManager->IsOnBoundary()) {
+ mparam[0] = lparam[0];
+ mparam[1] = lparam[4]/lparam[1];
+ mparam[2] = lparam[2];
+ mparam[3] = lparam[3];
+ mparam[4] = lparam[4];
+ return lparam[0];
+ }
+ // Try to cross the boundary and see what is next
+ Int_t nzero = 0;
+ while (length>TGeoShape::Tolerance()) {
+ currentnode = gGeoManager->GetCurrentNode();
+ if (snext<2.*TGeoShape::Tolerance()) nzero++;
+ else nzero = 0;
+ if (nzero>3) {
+ // This means navigation has problems on one boundary
+ // Try to cross by making a small step
+ printf("ERROR: cannot cross boundary\n");
+ mparam[0] = bparam[0]/step;
+ mparam[1] = bparam[1];
+ mparam[2] = bparam[2]/step;
+ mparam[3] = bparam[3]/step;
+ mparam[5] = bparam[5]/step;
+ mparam[4] = step;
+ mparam[0] = 0.; // if crash of navigation take mean density 0
+ mparam[1] = 1000000; // and infinite rad length
+ return bparam[0]/step;
+ }
+ mparam[6]+=1.;
+ step += snext;
+ bparam[1] += snext/lparam[1];
+ bparam[2] += snext*lparam[2];
+ bparam[3] += snext*lparam[3];
+ bparam[5] += snext*lparam[5];
+ bparam[0] += snext*lparam[0];
+
+ if (snext>=length) break;
+ if (!currentnode) break;
+ length -= snext;
+ //printf("%s snext=%f length=%f\n", currentnode->GetName(),snext,length);
+ material = currentnode->GetVolume()->GetMedium()->GetMaterial();
+ lparam[0] = material->GetDensity();
+ lparam[1] = material->GetRadLen();
+ lparam[2] = material->GetA();
+ lparam[3] = material->GetZ();
+ //printf(" %f %f %f %f\n",lparam[0],lparam[1],lparam[2],lparam[3]);
+ lparam[5] = lparam[3]/lparam[2];
+ if (material->IsMixture()) {
+ TGeoMixture * mixture = (TGeoMixture*)material;
+ lparam[5]=0;
+ Double_t sum =0;
+ for (Int_t iel=0;iel<mixture->GetNelements();iel++){
+ sum+= mixture->GetWmixt()[iel];
+ lparam[5]+= mixture->GetZmixt()[iel]*mixture->GetWmixt()[iel]/mixture->GetAmixt()[iel];
+ }
+ lparam[5]/=sum;
+ }
+ gGeoManager->FindNextBoundaryAndStep(length, kFALSE);
+ snext = gGeoManager->GetStep();
+ //printf("snext %f\n",snext);
+ }
+ mparam[0] = bparam[0]/step;
+ mparam[1] = bparam[1];
+ mparam[2] = bparam[2]/step;
+ mparam[3] = bparam[3]/step;
+ mparam[5] = bparam[5]/step;
+ return bparam[0]/step;
+}
+
+
+Bool_t
+AliTracker::PropagateTrackTo(AliExternalTrackParam *track, Double_t xToGo,
+Double_t mass, Double_t maxStep, Bool_t rotateTo, Double_t maxSnp){
+ //----------------------------------------------------------------
+ //
+ // Propagates the track to the plane X=xk (cm) using the magnetic field map
+ // and correcting for the crossed material.
+ //
+ // mass - mass used in propagation - used for energy loss correction
+ // maxStep - maximal step for propagation
+ //
+ // Origin: Marian Ivanov, Marian.Ivanov@cern.ch
+ //
+ //----------------------------------------------------------------
+ const Double_t kEpsilon = 0.00001;
+ Double_t xpos = track->GetX();
+ Double_t dir = (xpos<xToGo) ? 1.:-1.;
+ //
+ while ( (xToGo-xpos)*dir > kEpsilon){
+ Double_t step = dir*TMath::Min(TMath::Abs(xToGo-xpos), maxStep);
+ Double_t x = xpos+step;
+ Double_t xyz0[3],xyz1[3],param[7];
+ track->GetXYZ(xyz0); //starting global position
+
+ Double_t bz=GetBz(xyz0); // getting the local Bz
+
+ if (!track->GetXYZAt(x,bz,xyz1)) return kFALSE; // no prolongation
+ xyz1[2]+=kEpsilon; // waiting for bug correction in geo
+
+ if (TMath::Abs(track->GetSnpAt(x,bz)) >= maxSnp) return kFALSE;
+ if (!track->PropagateTo(x,bz)) return kFALSE;
+
+ MeanMaterialBudget(xyz0,xyz1,param);
+ Double_t xrho=param[0]*param[4], xx0=param[1];
+
+ if (!track->CorrectForMeanMaterial(xx0,xrho,mass)) return kFALSE;
+ if (rotateTo){
+ if (TMath::Abs(track->GetSnp()) >= maxSnp) return kFALSE;
+ track->GetXYZ(xyz0); // global position
+ Double_t alphan = TMath::ATan2(xyz0[1], xyz0[0]);
+ //
+ Double_t ca=TMath::Cos(alphan-track->GetAlpha()),
+ sa=TMath::Sin(alphan-track->GetAlpha());
+ Double_t sf=track->GetSnp(), cf=TMath::Sqrt(1.- sf*sf);
+ Double_t sinNew = sf*ca - cf*sa;
+ if (TMath::Abs(sinNew) >= maxSnp) return kFALSE;
+ if (!track->Rotate(alphan)) return kFALSE;
+ }
+ xpos = track->GetX();
+ }
+ return kTRUE;
+}
+
+void AliTracker::FillResiduals(const AliExternalTrackParam *t,
+ Double_t *p, Double_t *cov,
+ UShort_t id, Bool_t updated) {
+ //
+ // This function fills the histograms of residuals
+ // The array of these histos is external for this AliTracker class.
+ // Normally, this array belong to AliGlobalQADataMaker class.
+ //
+ if (!fFillResiduals) return;
+ if (!fResiduals) return;
+
+ const Double_t *residuals=t->GetResiduals(p,cov,updated);
+ if (!residuals) return;
+
+ TH1F *h=0;
+ AliGeomManager::ELayerID layer=AliGeomManager::VolUIDToLayer(id);
+ h=(TH1F*)fResiduals->At(2*layer-2);
+ h->Fill(residuals[0]);
+ h=(TH1F*)fResiduals->At(2*layer-1);
+ h->Fill(residuals[1]);
+
+ if (layer==5) {
+ if (p[1]<0) { // SSD1 absolute residuals
+ ((TH1F*)fResiduals->At(40))->Fill(t->GetY()-p[0]); //C side
+ ((TH1F*)fResiduals->At(41))->Fill(t->GetZ()-p[1]);
+ } else {
+ ((TH1F*)fResiduals->At(42))->Fill(t->GetY()-p[0]); //A side
+ ((TH1F*)fResiduals->At(43))->Fill(t->GetZ()-p[1]);
+ }
+ }
+ if (layer==6) { // SSD2 absolute residuals
+ if (p[1]<0) {
+ ((TH1F*)fResiduals->At(44))->Fill(t->GetY()-p[0]); //C side
+ ((TH1F*)fResiduals->At(45))->Fill(t->GetZ()-p[1]);
+ } else {
+ ((TH1F*)fResiduals->At(46))->Fill(t->GetY()-p[0]); //A side
+ ((TH1F*)fResiduals->At(47))->Fill(t->GetZ()-p[1]);
+ }
+ }
+
+}
+