#include <MdcTrackUtil.h>

Public Member Functions
	MdcTrackUtil ()

	~MdcTrackUtil ()

int	nLayerTrackPassed (const HepVector helix)

int	nLayerTrackPassed (const double helix[5])

HepVector	patRecPar2BesPar (const HepVector &helixPar)

HepSymMatrix	patRecErr2BesErr (const HepSymMatrix &err)

Static Public Member Functions
static MdcTrackUtil *	instance ()

Detailed Description

Definition at line 8 of file MdcTrackUtil.h.

Constructor & Destructor Documentation

◆ MdcTrackUtil()

MdcTrackUtil::MdcTrackUtil ( )

Definition at line 39 of file MdcTrackUtil.cxx.

                          {
  //Initalze magnetic flied 
  IService* svc;
  Gaudi::svcLocator()->getService("MagneticFieldSvc",svc);
  m_pIMF = dynamic_cast<IMagneticFieldSvc*> (svc);
  if(! m_pIMF){
    std::cout<<" ERROR Unable to open Magnetic field service "<<std::endl;
  }
  //get Bz for Check TEMP, Bz may be changed by run
  double gaussToTesla = 1000.;
  Bz = m_pIMF->getReferField()*gaussToTesla;
 
  // Initialize MdcGeomSvc
  Gaudi::svcLocator()->getService("MdcGeomSvc",svc);
  m_mdcGeomSvc= dynamic_cast<MdcGeomSvc*> (svc);
  if(! m_mdcGeomSvc){
    std::cout<<" FATAL Could not load MdcGeomSvc!  "<<std::endl;
  }
}

Referenced by instance().

◆ ~MdcTrackUtil()

MdcTrackUtil::~MdcTrackUtil ( )

inline

Definition at line 12 of file MdcTrackUtil.h.

12{};

Member Function Documentation

◆ instance()

MdcTrackUtil * MdcTrackUtil::instance ( )

static

Definition at line 31 of file MdcTrackUtil.cxx.

                                     {
  if( 0 == _myself ) {
    _myself = new MdcTrackUtil();
  }
  return _myself;
}

◆ nLayerTrackPassed() [1/2]

int MdcTrackUtil::nLayerTrackPassed ( const double helix[5] )

Definition at line 68 of file MdcTrackUtil.cxx.

                                                        {
  int nLayer = 0;
 
  for(unsigned iLayer=0; iLayer<43; iLayer++){
    //flightLength is the path length of track in the x-y plane
    //guess flightLength by the radius in middle of the wire.
    double rMidLayer = m_mdcGeomSvc->Layer(iLayer)->Radius();
    double flightLength = rMidLayer;
 
    HepPoint3D pivot(0.,0.,0.);
    double dz = helix[3];
    double c = CLHEP::c_light * 100.; //unit from m/s to cm/s
    double alpha = 1/(c * Bz);//~333.567
    double kappa = helix[2];
    double rc = (-1.)*alpha/kappa;
    //std::cout<<"MdcTrackUtil alpha   "<<alpha<<std::endl;
    double tanl = helix[4];
    double phi0 = helix[1];
    double phi = flightLength/rc + phi0;//turning angle
    double z = pivot.z() + dz - (alpha/kappa) * tanl * phi;
 
    double layerHalfLength = m_mdcGeomSvc->Layer(iLayer)->Length()/2.;
 
    //std::cout<<"MdcTrackUtil length  "<<layerHalfLength<<std::endl;
 
    if (fabs(z) < fabs(layerHalfLength)) ++nLayer;
  }
 
  return nLayer;
}

◆ nLayerTrackPassed() [2/2]

int MdcTrackUtil::nLayerTrackPassed ( const HepVector helix )

Definition at line 60 of file MdcTrackUtil.cxx.

                                                        {
  double helixParam[5];
  for(int i=0; i<5; ++i) helixParam[i] = helix[i];
 
  return nLayerTrackPassed(helixParam);
}

Referenced by nLayerTrackPassed().

◆ patRecErr2BesErr()

HepSymMatrix MdcTrackUtil::patRecErr2BesErr ( const HepSymMatrix & err )

Definition at line 117 of file MdcTrackUtil.cxx.

                                                                  {
  //error matrix
  //std::cout<<" err1  "<<err<<" "<<err.num_row()<<std::endl;
  //V(Y)=S * V(X) * ST , mS = S , mVy = V(Y) , err() = V(X)
  //int n = err.num_row();
  HepSymMatrix mS(err.num_row(),0);
  mS[0][0]=-1.;//dr0=-d0
  mS[1][1]=1.;
  mS[2][2]=Bz/-333.567;//pxy -> cpa
  mS[3][3]=1.;
  mS[4][4]=1.;
  HepSymMatrix mVy= err.similarity(mS);
  //std::cout<<" err2  "<<n<<" "<<mVy<<std::endl;
  return mVy;
}

◆ patRecPar2BesPar()

HepVector MdcTrackUtil::patRecPar2BesPar ( const HepVector & helixPar )

Definition at line 100 of file MdcTrackUtil.cxx.

                                                                 {
  HepVector helix(5,0);
  double d0 = -helixPar[0];    //cm
  double phi0 = helixPar[1]+ CLHEP::halfpi;
  double omega = Bz*helixPar[2]/-333.567;
  double z0 = helixPar[3];    //cm
  double tanl = helixPar[4];
  helix[0] = d0;
  helix[1] = phi0;
  helix[2] = omega;
  helix[3] = z0;
  helix[4] = tanl;
  //std::cout<<"helix   "<<helix<<std::endl;
  return helix;
}

The documentation for this class was generated from the following files:

Public Member Functions

Static Public Member Functions