SignedImpactParameter3D Class Reference

#include <SignedImpactParameter3D.h>

Public Member Functions
std::pair< bool, Measurement1D >	apply (const reco::TransientTrack &, const GlobalVector &direction, const reco::Vertex &vertex) const
int	id () const
	SignedImpactParameter3D ()

Static Public Member Functions
static std::pair< double, Measurement1D >	distanceWithJetAxis (const reco::TransientTrack &transientTrack, const GlobalVector &direction, const reco::Vertex &vertex)

Static Private Member Functions
static TrajectoryStateOnSurface	closestApproachToJet (const FreeTrajectoryState &, const reco::Vertex &, const GlobalVector &, const MagneticField *)
static GlobalVector	distance (const TrajectoryStateOnSurface &, const reco::Vertex &, const GlobalVector &)

Detailed Description

Threedimensional track impact parameter signed according to the jet direction

Definition at line 13 of file SignedImpactParameter3D.h.

Constructor & Destructor Documentation

SignedImpactParameter3D()

SignedImpactParameter3D::SignedImpactParameter3D ( )

inline

Definition at line 17 of file SignedImpactParameter3D.h.

{};

Member Function Documentation

apply()

pair< bool, Measurement1D > SignedImpactParameter3D::apply	(	const reco::TransientTrack &	transientTrack,
		const GlobalVector &	direction,
		const reco::Vertex &	vertex
	)		const

Definition at line 17 of file SignedImpactParameter3D.cc.

                                                                                     {
  double theValue = 0.;
  double theError = 0.;
  bool theIsValid = false;
 
  TrajectoryStateOnSurface TSOS = transientTrack.impactPointState();
 
  if (!TSOS.isValid()) {
    cout << "====>>>> SignedImpactParameter3D::apply : TSOS not valid = " << TSOS.isValid() << endl;
    return pair<bool, Measurement1D>(theIsValid, Measurement1D(0., 0.));
  }
 
  const FreeTrajectoryState* FTS = TSOS.freeTrajectoryState();
 
  const GlobalVector& JetDirection(direction);
 
  TrajectoryStateOnSurface theTSOS = closestApproachToJet(*FTS, vertex, JetDirection, transientTrack.field());
  theIsValid = theTSOS.isValid();
 
  if (theIsValid) {
    GlobalVector D = distance(theTSOS, vertex, JetDirection);
    GlobalVector J = JetDirection.unit();
    GlobalPoint vertexPosition(vertex.x(), vertex.y(), vertex.z());
    double theDistanceAlongJetAxis = J.dot(theTSOS.globalPosition() - vertexPosition);
    theValue = D.mag() * (theDistanceAlongJetAxis / abs(theDistanceAlongJetAxis));
 
    GlobalVector DD = D.unit();
    GlobalPoint T0 = theTSOS.globalPosition();
    GlobalVector T1 = theTSOS.globalMomentum();
    GlobalVector TT1 = T1.unit();
    GlobalVector Xi(T0.x() - vertex.position().x(), T0.y() - vertex.position().y(), T0.z() - vertex.position().z());
 
    AlgebraicVector6 deriv;
    AlgebraicVector3 deriv_v;
 
    deriv_v[0] = -DD.x();
    deriv_v[1] = -DD.y();
    deriv_v[2] = -DD.z();
 
    deriv[0] = DD.x();
    deriv[1] = DD.y();
    deriv[2] = DD.z();
    deriv[3] = -(TT1.dot(Xi) * DD.x()) / T1.mag();
    deriv[4] = -(TT1.dot(Xi) * DD.y()) / T1.mag();
    deriv[5] = -(TT1.dot(Xi) * DD.z()) / T1.mag();
 
    double E1 = ROOT::Math::Similarity(deriv, theTSOS.cartesianError().matrix());
    double E2 = ROOT::Math::Similarity(deriv_v, vertex.covariance());
    //    double E2 = RecoVertex::convertError(vertex.covariance()).matrix().similarity(deriv_v);
    //    double E2 = 0.; // no vertex error because of stupid use of hundreds of different types for same thing
    theError = sqrt(E1 + E2);
 
    Measurement1D A(theValue, theError);
 
    return pair<bool, Measurement1D>(theIsValid, A);
  } else {
    return pair<bool, Measurement1D>(theIsValid, Measurement1D(0., 0.));
  }  // endif (isValid)
}

References MaterialEffects_cfi::A, funct::abs(), TrajectoryStateOnSurface::cartesianError(), IPTools::closestApproachToJet(), gather_cfg::cout, L1DTConfigTraco_cff::DD, HLT_FULL_cff::distance, Vector3DBase< T, FrameTag >::dot(), reco::TransientTrack::field(), TrajectoryStateOnSurface::freeTrajectoryState(), TrajectoryStateOnSurface::globalMomentum(), TrajectoryStateOnSurface::globalPosition(), reco::TransientTrack::impactPointState(), TrajectoryStateOnSurface::isValid(), PV3DBase< T, PVType, FrameType >::mag(), CartesianTrajectoryError::matrix(), mathSSE::sqrt(), Vector3DBase< T, FrameTag >::unit(), bphysicsOniaDQM_cfi::vertex, PV3DBase< T, PVType, FrameType >::x(), PV3DBase< T, PVType, FrameType >::y(), and PV3DBase< T, PVType, FrameType >::z().

Referenced by heavyIonTools.ConfigureHeavyIons::__call__(), coreTools.RunOnData::__call__(), trackTools.MakeAODTrackCandidates::__call__(), runJetUncertainties.RunJetUncertainties::__call__(), metTools.AddMETCollection::__call__(), heavyIonTools.ProductionDefaults::__call__(), coreTools.RemoveMCMatching::__call__(), trackTools.MakePATTrackCandidates::__call__(), trigTools.SwitchOnTrigger::__call__(), runMETCorrectionsAndUncertainties.RunMETCorrectionsAndUncertainties::__call__(), heavyIonTools.SelectionDefaults::__call__(), heavyIonTools.DisbaleMonteCarloDeps::__call__(), trigTools.SwitchOnTriggerStandAlone::__call__(), tauTools.AddTauCollection::__call__(), trackTools.MakeTrackCandidates::__call__(), trigTools.SwitchOnTriggerMatching::__call__(), trigTools.SwitchOnTriggerMatchingStandAlone::__call__(), trigTools.SwitchOnTriggerMatchEmbedding::__call__(), jetTools.AddJetCollection::__call__(), jetTools.SwitchJetCollection::__call__(), jetTools.UpdateJetCollection::__call__(), jetTools.AddJetID::__call__(), jetTools.SetTagInfos::__call__(), and ImpactParameterAlgorithm::tag().

closestApproachToJet()

TrajectoryStateOnSurface SignedImpactParameter3D::closestApproachToJet ( const FreeTrajectoryState &  aFTS, const reco::Vertex &  vertex, const GlobalVector &  aJetDirection, const MagneticField *  field  )

staticprivate

Definition at line 79 of file SignedImpactParameter3D.cc.

                                                                                                   {
  GlobalVector J = aJetDirection.unit();
 
  Line::PositionType pos(GlobalPoint(vertex.x(), vertex.y(), vertex.z()));
  Line::DirectionType dir(J);
  Line Jet(pos, dir);
 
  AnalyticalTrajectoryExtrapolatorToLine TETL(field);
 
  return TETL.extrapolate(aFTS, Jet);
}

References DeadROC_duringRun::dir, AnalyticalTrajectoryExtrapolatorToLine::extrapolate(), L1TRate_cfi::Jet, Vector3DBase< T, FrameTag >::unit(), and bphysicsOniaDQM_cfi::vertex.

distance()

GlobalVector SignedImpactParameter3D::distance ( const TrajectoryStateOnSurface &  aTSOS, const reco::Vertex &  vertex, const GlobalVector &  aJetDirection  )

staticprivate

Definition at line 94 of file SignedImpactParameter3D.cc.

                                                                                  {
  Line::PositionType pos2(aTSOS.globalPosition());
  Line::DirectionType dir2((aTSOS.globalMomentum()).unit());
  Line T(pos2, dir2);
 
  GlobalPoint X = GlobalPoint(vertex.x(), vertex.y(), vertex.z());  // aVertex.position();
 
  GlobalVector D = T.distance(X);
 
  return D;
}

References L1TDiffHarvesting_cfi::dir2, TrajectoryStateOnSurface::globalMomentum(), TrajectoryStateOnSurface::globalPosition(), unit(), bphysicsOniaDQM_cfi::vertex, and X.

distanceWithJetAxis()

pair< double, Measurement1D > SignedImpactParameter3D::distanceWithJetAxis ( const reco::TransientTrack &  transientTrack, const GlobalVector &  direction, const reco::Vertex &  vertex  )

static

Return a pair: first is the decay length second is the distance of the track from jet axis

Definition at line 108 of file SignedImpactParameter3D.cc.

                                                                                               {
  double theDistanceAlongJetAxis(0.);
  double theDistanceToJetAxis(0.);
  double theLDist_err(0.);
  TrajectoryStateOnSurface TSOS = track.impactPointState();
 
  if (!TSOS.isValid()) {
    cout << "====>>>> SignedImpactParameter3D::distanceWithJetAxis : TSOS not valid = " << TSOS.isValid() << endl;
    return pair<double, Measurement1D>(theDistanceAlongJetAxis, Measurement1D(theDistanceToJetAxis, theLDist_err));
  }
 
  const FreeTrajectoryState* FTS = TSOS.freeTrajectoryState();
 
  const GlobalVector& jetDirection(direction);
 
  //
  // Check whether the track has been used in the vertex
  //
 
  //FIXME
  float weight = 0.;  //vertex.trackWeight(aRecTrack);
 
  TrajectoryStateOnSurface stateAtOrigin = track.impactPointState();
  TrajectoryStateOnSurface aTSOS = closestApproachToJet(*FTS, vertex, jetDirection, track.field());
  bool isValid = stateAtOrigin.isValid();
  //  bool IsValid= aTSOS.isValid();
 
  if (isValid) {
    //get the Track line at origin
    Line::PositionType pos(stateAtOrigin.globalPosition());
    Line::DirectionType dir((stateAtOrigin.globalMomentum()).unit());
    Line track(pos, dir);
    // get the Jet  line
    // Vertex vertex(vertex);
    GlobalVector jetVector = jetDirection.unit();
    Line::PositionType pos2(GlobalPoint(vertex.x(), vertex.y(), vertex.z()));
    Line::DirectionType dir2(jetVector);
    Line jet(pos2, dir2);
    // now compute the distance between the two lines
    // If the track has been used to refit the Primary vertex then sign it positively, otherwise negative
 
    theDistanceToJetAxis = (jet.distance(track)).mag();
    if (weight < 1)
      theDistanceToJetAxis = -theDistanceToJetAxis;
 
    // ... and the flight distance along the Jet axis.
    GlobalPoint V = jet.position();
    GlobalVector Q = dir - jetVector.dot(dir) * jetVector;
    GlobalVector P = jetVector - jetVector.dot(dir) * dir;
    theDistanceAlongJetAxis = P.dot(V - pos) / Q.dot(dir);
 
    //
    // get the covariance matrix of the vertex and compute the error on theDistanceToJetAxis
    //
 
 
    // build the vector of closest approach between lines
 
    GlobalVector H((jetVector.cross(dir).unit()));
 
    CLHEP::HepVector Hh(3);
    Hh[0] = H.x();
    Hh[1] = H.y();
    Hh[2] = H.z();
 
    //  theLDist_err = sqrt(vertexError.similarity(Hh));
 
    //    cout << "distance to jet axis : "<< theDistanceToJetAxis <<" and error : "<< theLDist_err<<endl;
    // Now the impact parameter ...
 
    /*    GlobalPoint T0 = track.position();
    GlobalVector D = (T0-V)- (T0-V).dot(dir) * dir;
    double IP = D.mag();    
    GlobalVector Dold = distance(aTSOS, aJet.vertex(), jetDirection);
    double IPold = Dold.mag();
*/
  }
  Measurement1D DTJA(theDistanceToJetAxis, theLDist_err);
 
  return pair<double, Measurement1D>(theDistanceAlongJetAxis, DTJA);
}

References IPTools::closestApproachToJet(), gather_cfg::cout, Vector3DBase< T, FrameTag >::cross(), DeadROC_duringRun::dir, L1TDiffHarvesting_cfi::dir2, Vector3DBase< T, FrameTag >::dot(), TrajectoryStateOnSurface::freeTrajectoryState(), TrajectoryStateOnSurface::globalMomentum(), TrajectoryStateOnSurface::globalPosition(), class-composition::H, TrajectoryStateOnSurface::isValid(), metsig::jet, mag(), class-composition::Q, HLT_FULL_cff::track, Vector3DBase< T, FrameTag >::unit(), unit(), cms::cuda::V, and bphysicsOniaDQM_cfi::vertex.

id()

int SignedImpactParameter3D::id ( void  ) const

inline

Definition at line 23 of file SignedImpactParameter3D.h.

{ return 2; }