Pmt Namespace Reference

Enumerations
enum	ParamDefs {   d0 = 0, z0 = 1, phi0 = 2, theta = 3,   qOverP = 4, x = 0, y = 1, z = 2 }
	This file defines the parameter enums in the Trk namespace. More...

Functions
Eigen::Vector3d	getPosition (const xAOD::TrackParticle &trk)
double	getSigmaD0 (const xAOD::TrackParticle &trk, const Eigen::Matrix2d &vtxCov)
double	getSigmaD0 (const xAOD::TrackParticle &trk, const xAOD::Vertex &vtx)
double	getSigmaD0WithRespectToBeamspot (const xAOD::TrackParticle &trk, const xAOD::EventInfo &evt)
double	getSigmaZ0SinTheta (const xAOD::TrackParticle &trk, double vxZCov)
double	getSigmaZ0SinTheta (const xAOD::TrackParticle &trk, const xAOD::Vertex &vtx)

Enumeration Type Documentation

ParamDefs

enum Pmt::ParamDefs

This file defines the parameter enums in the Trk namespace.

Note that the enums refer to the [] operator and not to the () operator which makes a big difference in classes inherited or used from CLHEP. CLHEP::HepVector and not CLHEP::Hep2Vector is taken, as CLHEP::Hep2Vector provides additional functions like x(), y(), phi() which might be meaningless when using specific natural detector frames.

Usage examples:

• Access the y-coordinate of the cartesian local frame:
  LocalPosition locpos(2.3, 4.5);
  double x = locpos[Trk::locX];
• Access the eta-value of a track state on a surface (Tsos):
  double theEta = Tsos[Trk::eta]
• Access the eta-value of a track state on a surface (Tsos):
  double theEta = Tsos[Trk::eta]

Author

Andre.nosp@m.as.S.nosp@m.alzbu.nosp@m.rger.nosp@m.@cern.nosp@m..ch

Enumerator
d0
z0
phi0
theta
qOverP
x
y
z

Definition at line 26 of file PoorMansIpAugmenterAlg.cxx.

                 {
    // Track defining parameters
    d0 = 0,
    z0 = 1,
    phi0 = 2,
    theta = 3,
    qOverP = 4,
    // Cartesian
    x = 0,
    y = 1,
    z = 2,
  };

Function Documentation

getPosition()

Eigen::Vector3d Pmt::getPosition

(

const xAOD::TrackParticle &

trk

)

Definition at line 43 of file PoorMansIpAugmenterAlg.cxx.

                                  {
    double d0 = trk.d0();
    double phi = trk.phi();
    return Amg::Vector3D(
      d0 * -std::sin(phi),
      d0 *  std::cos(phi),
      trk.z0());
  }

getSigmaD0() [1/2]

double Pmt::getSigmaD0	(	const xAOD::TrackParticle &	trk,
		const Eigen::Matrix2d &	vtxCov
	)

Definition at line 55 of file PoorMansIpAugmenterAlg.cxx.

                                                 {
 
    // start with the track part
    double trackComponent = trk.definingParametersCovMatrixDiagVec().at(
      Pmt::d0);
 
    // now do the vertex part
    double phi = trk.phi();
    // The sign seems inverted below, but maybe that doesn't
    // matter. I'm just following TrackToVertexIPEstimator...
    Eigen::Vector2d vtxJacobian(-std::sin(phi), std::cos(phi));
    double vertexComponent = vtxJacobian.transpose()*vtxCov*vtxJacobian;
 
    return std::sqrt(trackComponent + vertexComponent);
 
  }

getSigmaD0() [2/2]

double Pmt::getSigmaD0	(	const xAOD::TrackParticle &	trk,
		const xAOD::Vertex &	vtx
	)

Definition at line 73 of file PoorMansIpAugmenterAlg.cxx.

                                           {
 
    // first two elements of the vertex covariance is xy
    Eigen::Matrix2d vtxCov = vtx.covariancePosition().block<2,2>(0,0);
    return getSigmaD0(trk, vtxCov);
 
  }

getSigmaD0WithRespectToBeamspot()

double Pmt::getSigmaD0WithRespectToBeamspot	(	const xAOD::TrackParticle &	trk,
		const xAOD::EventInfo &	evt
	)

Definition at line 82 of file PoorMansIpAugmenterAlg.cxx.

                                                                   {
    Eigen::Matrix2d bsCov;
    // based on what I read in the beamspot code [1] and some code
    // that copies it to the EventInfo [2] I'm pretty sure the
    // beamPosSigmaX and beamPosSigmaY need to be squared in the
    // covariance matrix, whereas beamPosSigmaXY does not.
    //
    // [1]: https://acode-browser1.usatlas.bnl.gov/lxr/source/athena/InnerDetector/InDetConditions/BeamSpotConditionsData/src/BeamSpotData.cxx
    // [2]: https://acode-browser1.usatlas.bnl.gov/lxr/source/athena/Simulation/BeamEffects/src/BeamSpotFixerAlg.cxx#0068
    bsCov(0, 0) = std::pow(evt.beamPosSigmaX(),2);
    bsCov(0, 1) = evt.beamPosSigmaXY();
    bsCov(1, 0) = evt.beamPosSigmaXY();
    bsCov(1, 1) = std::pow(evt.beamPosSigmaY(),2);
    return getSigmaD0(trk, bsCov);
  }

getSigmaZ0SinTheta() [1/2]

double Pmt::getSigmaZ0SinTheta	(	const xAOD::TrackParticle &	trk,
		const xAOD::Vertex &	vtx
	)

Definition at line 122 of file PoorMansIpAugmenterAlg.cxx.

                                                   {
    double vxZCov = vtx.covariancePosition()(Pmt::z,Pmt::z);
    return getSigmaZ0SinTheta(trk, vxZCov);
  }

getSigmaZ0SinTheta() [2/2]

double Pmt::getSigmaZ0SinTheta	(	const xAOD::TrackParticle &	trk,
		double	vxZCov
	)

Definition at line 100 of file PoorMansIpAugmenterAlg.cxx.

                                           {
 
    // first do the track part
    const auto& fullCov = trk.definingParametersCovMatrix();
    Eigen::Matrix2d trkCov;
    trkCov(0,0)=fullCov(Pmt::z0,    Pmt::z0);
    trkCov(0,1)=fullCov(Pmt::z0,    Pmt::theta);
    trkCov(1,0)=fullCov(Pmt::theta, Pmt::z0);
    trkCov(1,1)=fullCov(Pmt::theta, Pmt::theta);
    double theta = trk.theta();
    Eigen::Vector2d trkJacobian(
      std::sin(theta),
      trk.z0()*std::cos(theta));
    double trackComponent = trkJacobian.transpose()*trkCov*trkJacobian;
 
    // now do the vertex part
    double vertexComponent = std::sin(theta)*vxZCov*std::sin(theta);
 
    return std::sqrt(trackComponent + vertexComponent);
 
  }