MdcTrackUtil Class Reference

#include <MdcTrackUtil.h>

List of all members.

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 ()
Private Attributes
MdcGeomSvc *	m_mdcGeomSvc
IMagneticFieldSvc *	m_pIMF
double	Bz
Static Private Attributes
static MdcTrackUtil *	_myself = 0

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Detailed Description

Definition at line 8 of file MdcTrackUtil.h.

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Constructor & Destructor Documentation

MdcTrackUtil::MdcTrackUtil

(

)

Definition at line 39 of file MdcTrackUtil.cxx.

References Bz, IMagneticFieldSvc::getReferField(), m_mdcGeomSvc, and m_pIMF.

Referenced by instance().

                          {
  //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;
  }
}

MdcTrackUtil::~MdcTrackUtil

(

)

[inline]

Definition at line 12 of file MdcTrackUtil.h.

{};

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Member Function Documentation

MdcTrackUtil * MdcTrackUtil::instance

(

)

[static]

Definition at line 31 of file MdcTrackUtil.cxx.

References _myself, and MdcTrackUtil().

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

int MdcTrackUtil::nLayerTrackPassed

(

const double

helix[5]

)

Definition at line 68 of file MdcTrackUtil.cxx.

References alpha, Bz, MdcGeomSvc::Layer(), MdcGeoLayer::Length(), m_mdcGeomSvc, phi0, and MdcGeoLayer::Radius().

                                                        {
  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;
}

int MdcTrackUtil::nLayerTrackPassed

(

const HepVector

helix

)

Definition at line 60 of file MdcTrackUtil.cxx.

References genRecEmupikp::i.

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

  return nLayerTrackPassed(helixParam);
}

HepSymMatrix MdcTrackUtil::patRecErr2BesErr

(

const HepSymMatrix &

err

)

Definition at line 117 of file MdcTrackUtil.cxx.

References Bz.

                                                                  {
  //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;
}

HepVector MdcTrackUtil::patRecPar2BesPar

(

const HepVector &

helixPar

)

Definition at line 100 of file MdcTrackUtil.cxx.

References Bz, and phi0.

                                                                 {
  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;
}

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Member Data Documentation

MdcTrackUtil * MdcTrackUtil::_myself = 0 [static, private]

Definition at line 20 of file MdcTrackUtil.h.

Referenced by instance().

double MdcTrackUtil::Bz [private]

Definition at line 24 of file MdcTrackUtil.h.

Referenced by MdcTrackUtil(), nLayerTrackPassed(), patRecErr2BesErr(), and patRecPar2BesPar().

MdcGeomSvc* MdcTrackUtil::m_mdcGeomSvc [private]

Definition at line 22 of file MdcTrackUtil.h.

Referenced by MdcTrackUtil(), and nLayerTrackPassed().

IMagneticFieldSvc* MdcTrackUtil::m_pIMF [private]

Definition at line 23 of file MdcTrackUtil.h.

Referenced by MdcTrackUtil().

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