PXDRecoHit Class Reference

PXDRecoHit - an extended form of PXDCluster containing geometry information. More...

#include <PXDRecoHit.h>

Inheritance diagram for PXDRecoHit:

Public Member Functions
	PXDRecoHit ()
	Default constructor for ROOT IO.
	PXDRecoHit (const PXDTrueHit *hit, const genfit::TrackCandHit *trackCandHit=NULL, float sigmaU=-1, float sigmaV=-1)
	Construct PXDRecoHit from a PXDTrueHit for Monte Carlo based tracking.
	PXDRecoHit (const PXDCluster *hit, float sigmaU, float sigmaV, float covUV)
	Construct PXDRecoHit from a PXD cluster.
	PXDRecoHit (const PXDCluster *hit, const genfit::TrackCandHit *trackCandHit=NULL)
	Construct PXDRecoHit from a PXD cluster This constructor is intended as a temporary solution for people who want to test the impact of realistic clusters right now using the current tracking stack and before the final error handling is implemented.
genfit::AbsMeasurement *	clone () const override
	Creating a deep copy of this hit.
virtual std::vector< genfit::MeasurementOnPlane * >	constructMeasurementsOnPlane (const genfit::StateOnPlane &state) const override
	Methods that actually interface to Genfit.
VxdID	getSensorID () const
	Get the compact ID.
const PXDTrueHit *	getTrueHit () const
	Get pointer to the TrueHit used when creating this RecoHit, can be NULL if created from something else.
const PXDCluster *	getCluster () const
	Get pointer to the Cluster used when creating this RecoHit, can be NULL if created from something else.
float	getU () const
	Get u coordinate.
float	getV () const
	Get v coordinate.
float	getUVariance () const
	Get u coordinate variance.
float	getVVariance () const
	Get v coordinate variance.
float	getUVCov () const
	Get u-v error covariance.
float	getEnergyDep () const
	Get deposited energy.
float	getShapeLikelyhood (const genfit::StateOnPlane &state) const
	Get deposited energy error.
virtual const genfit::AbsHMatrix *	constructHMatrix (const genfit::AbsTrackRep *) const override
	Construct the hessian matrix.

Private Types
enum	{ HIT_DIMENSIONS = 2 }

Private Member Functions
void	setDetectorPlane ()
	Set up Detector plane information.
TVectorD	applyPlanarDeformation (TVectorD hitCoords, std::vector< double > planarParameters, const genfit::StateOnPlane &state) const
	Apply planar deformation of sensors.

Private Attributes
unsigned short	m_sensorID
	Unique sensor identifier.
const PXDTrueHit *	m_trueHit
	Pointer to the TrueHit used when creating this object.
const PXDCluster *	m_cluster
	transient member (not written out during streaming)
float	m_energyDep
	transient member (not written out during streaming)

Detailed Description

PXDRecoHit - an extended form of PXDCluster containing geometry information.

To create a list of PXDRecoHits for all PXDTrueHits belonging to one MCParticle do something like:

//Get the MCParticle in question
MCParticle* mcParticle = ...
//Assume some error on the position
float sigmaU = 10 * Unit::um;
float sigmaV = 15 * Unit::um;
 
//Iterate over the relation and create a list of hits
vector<PXDRecoHit*> hits;
RelationIndex<MCParticle,PXDTrueHit> relMCTrueHit;
RelationIndex<MCParticle,PXDTrueHit>::range_from it = relMCTrueHit.getElementsFrom(mcParticle);
for(; it.first!=it.second; ++it.first){
  hits.push_back(new PXDRecoHit(it.first->to, sigmaU, sigmaV));
}

Definition at line 49 of file PXDRecoHit.h.

Member Enumeration Documentation

anonymous enum

anonymous enum

private

Enumerator
HIT_DIMENSIONS	sensitive Dimensions of the Hit

Definition at line 134 of file PXDRecoHit.h.

{ HIT_DIMENSIONS = 2  };

Constructor & Destructor Documentation

PXDRecoHit() [1/4]

PXDRecoHit

(

)

Default constructor for ROOT IO.

Definition at line 26 of file PXDRecoHit.cc.

                      :
  genfit::PlanarMeasurement(HIT_DIMENSIONS), m_sensorID(0), m_trueHit(0), m_cluster(0),
  m_energyDep(0)//, m_energyDepError(0)
{}

PXDRecoHit() [2/4]

PXDRecoHit ( const PXDTrueHit *  hit, const genfit::TrackCandHit *  trackCandHit = NULL, float  sigmaU = -1, float  sigmaV = -1  )

explicit

Construct PXDRecoHit from a PXDTrueHit for Monte Carlo based tracking.

This requires a valid random number generator to be initialized at gRandom. The Hit position will be smeared using a gaussian smearing with sigmaU and sigmaV along u and v respectively

If one of the errors is set <0, a default resolution will be assumed for both values by dividing the pixel size by sqrt(12).

Parameters

hit	PXDTrueHit to use as base
trackCandHit	actually not used, should be removed?
sigmaU	Error of the Hit along u
sigmaV	Error of the Hit along v

Definition at line 31 of file PXDRecoHit.cc.

                                                                                                  :
  genfit::PlanarMeasurement(HIT_DIMENSIONS), m_sensorID(0), m_trueHit(hit), m_cluster(0),
  m_energyDep(0)//, m_energyDepError(0)
{
  if (!gRandom) B2FATAL("gRandom not initialized, please set up gRandom first");
 
  // Set the sensor UID
  m_sensorID = hit->getSensorID();
 
  //If no error is given, estimate the error by dividing the pixel size by sqrt(12)
  if (sigmaU < 0 || sigmaV < 0) {
    const PXD::SensorInfo& geometry = dynamic_cast<const PXD::SensorInfo&>(VXD::GeoCache::getInstance().getSensorInfo(m_sensorID));
    sigmaU = geometry.getUPitch(hit->getV()) / sqrt(12);
    sigmaV = geometry.getVPitch(hit->getV()) / sqrt(12);
  }
 
  // Set positions
  rawHitCoords_(0) = gRandom->Gaus(hit->getU(), sigmaU);
  rawHitCoords_(1) = gRandom->Gaus(hit->getV(), sigmaV);
  // Set the error covariance matrix
  rawHitCov_(0, 0) = sigmaU * sigmaU;
  rawHitCov_(0, 1) = 0;
  rawHitCov_(1, 0) = 0;
  rawHitCov_(1, 1) = sigmaV * sigmaV;
  // Set physical parameters
  m_energyDep = hit->getEnergyDep();
  // Setup geometry information
  setDetectorPlane();
}

PXDRecoHit() [3/4]

PXDRecoHit ( const PXDCluster *  hit, float  sigmaU, float  sigmaV, float  covUV  )

explicit

Construct PXDRecoHit from a PXD cluster.

For users that want to supply their own errors on construction

Parameters

hit	PXDCluster to use as base
sigmaU	Error of the Hit along u
sigmaV	Error of the Hit along v
covUV	Covariance between u and v

Definition at line 61 of file PXDRecoHit.cc.

                                                                                    :
  genfit::PlanarMeasurement(HIT_DIMENSIONS), m_sensorID(0), m_trueHit(0), m_cluster(hit),
  m_energyDep(0)//, m_energyDepError(0)
{
  // Set the sensor UID
  m_sensorID = hit->getSensorID();
  // Set positions
  rawHitCoords_(0) = hit->getU();
  rawHitCoords_(1) = hit->getV();
  // Set the error covariance matrix
  rawHitCov_(0, 0) = sigmaU * sigmaU;
  rawHitCov_(0, 1) = covUV;
  rawHitCov_(1, 0) = covUV;
  rawHitCov_(1, 1) = sigmaV * sigmaV;
  // Set physical parameters
  const PXD::SensorInfo& SensorInfo = dynamic_cast<const PXD::SensorInfo&>(VXD::GeoCache::getInstance().getSensorInfo(m_sensorID));
  auto ADUToEnergy = PXD::PXDGainCalibrator::getInstance().getADUToEnergy(m_sensorID, SensorInfo.getUCellID(hit->getU()),
                     SensorInfo.getVCellID(hit->getV()));
  m_energyDep = hit->getCharge() * ADUToEnergy;
  //m_energyDepError = 0;
  // Setup geometry information
  setDetectorPlane();
}

PXDRecoHit() [4/4]

PXDRecoHit ( const PXDCluster *  hit, const genfit::TrackCandHit *  trackCandHit = NULL  )

explicit

Construct PXDRecoHit from a PXD cluster This constructor is intended as a temporary solution for people who want to test the impact of realistic clusters right now using the current tracking stack and before the final error handling is implemented.

The pitch / sqrt(12) will be added as measurement error estimation. This is of course not the exact error of the cluster and one cannot expect perfect tracking results when using this constructor

Parameters

hit	PXDCluster to use as base
trackCandHit	actually not used, should be removed?

Definition at line 86 of file PXDRecoHit.cc.

                                                                      :
  genfit::PlanarMeasurement(HIT_DIMENSIONS), m_sensorID(0), m_trueHit(0), m_cluster(hit),
  m_energyDep(0)//, m_energyDepError(0)
{
  // Set the sensor UID
  m_sensorID = hit->getSensorID();
  // Set positions
  rawHitCoords_(0) = hit->getU();
  rawHitCoords_(1) = hit->getV();
  // Set the error covariance matrix
  rawHitCov_(0, 0) = hit->getUSigma() * hit->getUSigma();
  rawHitCov_(0, 1) = hit->getRho() * hit->getUSigma() * hit->getVSigma();
  rawHitCov_(1, 0) = hit->getRho() * hit->getUSigma() * hit->getVSigma();
  rawHitCov_(1, 1) = hit->getVSigma() * hit->getVSigma();
  // Set physical parameters
  const PXD::SensorInfo& SensorInfo = dynamic_cast<const PXD::SensorInfo&>(VXD::GeoCache::getInstance().getSensorInfo(m_sensorID));
  auto ADUToEnergy = PXD::PXDGainCalibrator::getInstance().getADUToEnergy(m_sensorID, SensorInfo.getUCellID(hit->getU()),
                     SensorInfo.getVCellID(hit->getV()));
  m_energyDep = hit->getCharge() * ADUToEnergy;
  //m_energyDepError = 0;
  // Setup geometry information
  setDetectorPlane();
}

Member Function Documentation

applyPlanarDeformation()

TVectorD applyPlanarDeformation ( TVectorD  hitCoords, std::vector< double >  planarParameters, const genfit::StateOnPlane &  state  ) const

private

Apply planar deformation of sensors.

Definition at line 148 of file PXDRecoHit.cc.

{
  // Legendre parametrization of deformation
  auto L1 = [](double x) {return x;};
  auto L2 = [](double x) {return (3 * x * x - 1) / 2;};
  auto L3 = [](double x) {return (5 * x * x * x - 3 * x) / 2;};
  auto L4 = [](double x) {return (35 * x * x * x * x - 30 * x * x + 3) / 8;};
 
  const PXD::SensorInfo& geometry = dynamic_cast<const PXD::SensorInfo&>(VXD::GeoCache::getInstance().getSensorInfo(m_sensorID));
 
  double u = hitCoords[0];
  double v = hitCoords[1];
  double width = geometry.getWidth(v);              // Width of sensor (U side)
  double length = geometry.getLength();             // Length of sensor (V side)
  u = u * 2 / width;                                // Legendre parametrization required U in (-1, 1)
  v = v * 2 / length;                               // Legendre parametrization required V in (-1, 1)
 
  /* Planar deformation using Legendre parametrization
     w(u, v) = L_{31} * L2(u) + L_{32} * L1(u) * L1(v) + L_{33} * L2(v) +
               L_{41} * L3(u) + L_{42} * L2(u) * L1(v) + L_{43} * L1(u) * L2(v) + L_{44} * L3(v) +
               L_{51} * L4(u) + L_{52} * L3(u) * L1(v) + L_{53} * L2(u) * L2(v) + L_{54} * L1(u) * L3(v) + L_{55} * L4(v); */
  double dw =
    planarParameters[0] * L2(u) + planarParameters[1] * L1(u) * L1(v) + planarParameters[2] * L2(v) +
    planarParameters[3] * L3(u) + planarParameters[4] * L2(u) * L1(v) + planarParameters[5] * L1(u) * L2(v) + planarParameters[6] * L3(
      v) +
    planarParameters[7] * L4(u) + planarParameters[8] * L3(u) * L1(v) + planarParameters[9] * L2(u) * L2(v) + planarParameters[10] * L1(
      u) * L3(v) + planarParameters[11] * L4(v);
 
  double du_dw = state.getState()[1]; // slope in U direction
  double dv_dw = state.getState()[2]; // slope in V direction
 
  u = u * width / 2;  // from Legendre to Local parametrization
  v = v * length / 2; // from Legendre to Local parametrization
 
  TVectorD pos(2);
 
  pos[0] = u + dw * du_dw;
  pos[1] = v + dw * dv_dw;
 
  return pos;
}

clone()

genfit::AbsMeasurement * clone ( ) const

override

Creating a deep copy of this hit.

Definition at line 110 of file PXDRecoHit.cc.

{
  return new PXDRecoHit(*this);
}

constructHMatrix()

virtual const genfit::AbsHMatrix * constructHMatrix ( const genfit::AbsTrackRep *  ) const

inlineoverridevirtual

Construct the hessian matrix.

Definition at line 130 of file PXDRecoHit.h.

{ return new genfit::HMatrixUV(); };

constructMeasurementsOnPlane()

std::vector< genfit::MeasurementOnPlane * > constructMeasurementsOnPlane ( const genfit::StateOnPlane &  state ) const

overridevirtual

Methods that actually interface to Genfit.

Definition at line 191 of file PXDRecoHit.cc.

{
  // Track-based update only takes place when the RecoHit has an associated cluster
  if (this->getCluster()) {
    // Check if we can correct position coordinates based on track info
    const TVectorD& state5 = state.getState();
    auto offset = PXD::PXDClusterPositionEstimator::getInstance().getClusterOffset(*this->getCluster(), state5[1], state5[2]);
 
    if (offset != nullptr) {
      // Found a valid offset, lets apply it
      const Belle2::VxdID& sensorID = (*this->getCluster()).getSensorID();
      const Belle2::PXD::SensorInfo& Info = dynamic_cast<const Belle2::PXD::SensorInfo&>(VXD::GeoCache::getInstance().getSensorInfo(
                                              sensorID));
      double posU = Info.getUCellPosition((*this->getCluster()).getUStart());
      double posV = Info.getVCellPosition((*this->getCluster()).getVStart());
 
      TVectorD hitCoords(2);
      hitCoords(0) = posU + offset->getU();
      hitCoords(1) = posV + offset->getV();
      TMatrixDSym hitCov(2);
      hitCov(0, 0) = offset->getUSigma2();
      hitCov(0, 1) = offset->getUVCovariance();
      hitCov(1, 0) = offset->getUVCovariance();
      hitCov(1, 1) = offset->getVSigma2();
 
      // Apply planar deformation
      TVectorD pos = applyPlanarDeformation(hitCoords, VXD::GeoCache::getInstance().getSensorInfo(m_sensorID).getSurfaceParameters(),
                                            state);
 
      return std::vector<genfit::MeasurementOnPlane*>(1, new genfit::MeasurementOnPlane(
                                                        pos, hitCov, state.getPlane(), state.getRep(), this->constructHMatrix(state.getRep())
                                                      ));
    }
  }
 
  // Apply planar deformation
  TVectorD pos = applyPlanarDeformation(rawHitCoords_, VXD::GeoCache::getInstance().getSensorInfo(m_sensorID).getSurfaceParameters(),
                                        state);
 
  // If we reach here, we can do no better than what we have
  return std::vector<genfit::MeasurementOnPlane*>(1, new genfit::MeasurementOnPlane(
                                                    pos, rawHitCov_, state.getPlane(), state.getRep(), this->constructHMatrix(state.getRep())
                                                  ));
}

getCluster()

const PXDCluster * getCluster ( ) const

inline

Get pointer to the Cluster used when creating this RecoHit, can be NULL if created from something else.

Definition at line 106 of file PXDRecoHit.h.

{ return m_cluster; }

getEnergyDep()

float getEnergyDep ( ) const

inline

Get deposited energy.

Definition at line 121 of file PXDRecoHit.h.

{ return m_energyDep; }

getSensorID()

VxdID getSensorID ( ) const

inline

Get the compact ID.

Definition at line 101 of file PXDRecoHit.h.

{ return m_sensorID; }

getShapeLikelyhood()

float getShapeLikelyhood

(

const genfit::StateOnPlane &

state

)

const

Get deposited energy error.

Get the likelyhood that cluster shape is likely to be created from track state.

Definition at line 136 of file PXDRecoHit.cc.

{
  // We need an associated cluster
  if (this->getCluster()) {
    // Likelyhood depends on the fitted incidence angles into the sensor
    const TVectorD& state5 = state.getState();
    return PXD::PXDClusterPositionEstimator::getInstance().getShapeLikelyhood(*this->getCluster(), state5[1], state5[2]);
  }
  // If we reach here, we can do no better than return zero
  return 0;
}

getTrueHit()

const PXDTrueHit * getTrueHit ( ) const

inline

Get pointer to the TrueHit used when creating this RecoHit, can be NULL if created from something else.

Definition at line 104 of file PXDRecoHit.h.

{ return m_trueHit; }

getU()

float getU ( ) const

inline

Get u coordinate.

Definition at line 109 of file PXDRecoHit.h.

{ return rawHitCoords_(0); }

getUVariance()

float getUVariance ( ) const

inline

Get u coordinate variance.

Definition at line 114 of file PXDRecoHit.h.

{ return rawHitCov_(0, 0); }

getUVCov()

float getUVCov ( ) const

inline

Get u-v error covariance.

Definition at line 118 of file PXDRecoHit.h.

{ return rawHitCov_(0, 1); }

getV()

float getV ( ) const

inline

Get v coordinate.

Definition at line 111 of file PXDRecoHit.h.

{ return rawHitCoords_(1); }

getVVariance()

float getVVariance ( ) const

inline

Get v coordinate variance.

Definition at line 116 of file PXDRecoHit.h.

{ return rawHitCov_(1, 1); }

setDetectorPlane()

void setDetectorPlane ( )

private

Set up Detector plane information.

Definition at line 116 of file PXDRecoHit.cc.

{
  // Construct a finite detector plane and set it.
  const PXD::SensorInfo& geometry = dynamic_cast<const PXD::SensorInfo&>(VXD::GeoCache::getInstance().getSensorInfo(m_sensorID));
 
  // Construct vectors o, u, v
  ROOT::Math::XYZVector uLocal(1, 0, 0);
  ROOT::Math::XYZVector vLocal(0, 1, 0);
  ROOT::Math::XYZVector origin  = geometry.pointToGlobal(ROOT::Math::XYZVector(0, 0, 0), true);
  ROOT::Math::XYZVector uGlobal = geometry.vectorToGlobal(uLocal, true);
  ROOT::Math::XYZVector vGlobal = geometry.vectorToGlobal(vLocal, true);
 
  //Construct the detector plane
  VXD::SensorPlane* finitePlane = new VXD::SensorPlane(m_sensorID, 20.0, 20.0);
  genfit::SharedPlanePtr detPlane(new genfit::DetPlane(XYZToTVector(origin), XYZToTVector(uGlobal), XYZToTVector(vGlobal),
                                                       finitePlane));
  setPlane(detPlane, m_sensorID);
}

Member Data Documentation

m_cluster

const PXDCluster* m_cluster

private

transient member (not written out during streaming)

Pointer to the Cluster used when creating this object

Definition at line 140 of file PXDRecoHit.h.

m_energyDep

float m_energyDep

private

transient member (not written out during streaming)

deposited energy.

Definition at line 141 of file PXDRecoHit.h.

m_sensorID

unsigned short m_sensorID

private

Unique sensor identifier.

Definition at line 136 of file PXDRecoHit.h.

m_trueHit

const PXDTrueHit* m_trueHit

private

Pointer to the TrueHit used when creating this object.

Definition at line 138 of file PXDRecoHit.h.

---

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

• pxd/reconstruction/include/PXDRecoHit.h
• pxd/reconstruction/src/PXDRecoHit.cc