TSCPBuilderNoMaterial Class Reference

#include <TSCPBuilderNoMaterial.h>

Inheritance diagram for TSCPBuilderNoMaterial:

Public Member Functions
virtual TrajectoryStateClosestToPoint	operator() (const FTS &originalFTS, const GlobalPoint &referencePoint) const
virtual TrajectoryStateClosestToPoint	operator() (const TSOS &originalTSOS, const GlobalPoint &referencePoint) const
virtual	~TSCPBuilderNoMaterial ()
Public Member Functions inherited from TrajectoryStateClosestToPointBuilder
bool	positionEqual (const GlobalPoint &ptB, const GlobalPoint &ptA) const
virtual	~TrajectoryStateClosestToPointBuilder ()

Private Types
typedef Point3DBase< double, GlobalTag >	GlobalPointDouble
typedef Vector3DBase< double, GlobalTag >	GlobalVectorDouble
typedef std::pair< bool, FreeTrajectoryState >	PairBoolFTS

Private Member Functions
PairBoolFTS	createFTSatTransverseImpactPoint (const FTS &originalFTS, const GlobalPoint &referencePoint) const
PairBoolFTS	createFTSatTransverseImpactPointCharged (const FTS &originalFTS, const GlobalPoint &referencePoint) const
PairBoolFTS	createFTSatTransverseImpactPointNeutral (const FTS &originalFTS, const GlobalPoint &referencePoint) const

Additional Inherited Members
Public Types inherited from TrajectoryStateClosestToPointBuilder
typedef FreeTrajectoryState	FTS
typedef TrajectoryStateOnSurface	TSOS
Protected Member Functions inherited from TrajectoryStateClosestToPointBuilder
TrajectoryStateClosestToPoint	constructTSCP (const FTS &originalFTS, const GlobalPoint &referencePoint) const

Detailed Description

This class builds a TrajectoryStateClosestToPoint given an original TrajectoryStateOnSurface or FreeTrajectoryState. This new state is then defined at the point of closest approach to the reference point. In case the propagation was not successful, this state can be invalid.

Definition at line 16 of file TSCPBuilderNoMaterial.h.

Member Typedef Documentation

typedef Point3DBase< double, GlobalTag> TSCPBuilderNoMaterial::GlobalPointDouble

private

Definition at line 31 of file TSCPBuilderNoMaterial.h.

typedef Vector3DBase< double, GlobalTag> TSCPBuilderNoMaterial::GlobalVectorDouble

private

Definition at line 32 of file TSCPBuilderNoMaterial.h.

typedef std::pair<bool, FreeTrajectoryState> TSCPBuilderNoMaterial::PairBoolFTS

private

Definition at line 33 of file TSCPBuilderNoMaterial.h.

Constructor & Destructor Documentation

virtual TSCPBuilderNoMaterial::~TSCPBuilderNoMaterial ( )

inlinevirtual

Definition at line 21 of file TSCPBuilderNoMaterial.h.

{}

Member Function Documentation

TSCPBuilderNoMaterial::PairBoolFTS TSCPBuilderNoMaterial::createFTSatTransverseImpactPoint ( const FTS &  originalFTS, const GlobalPoint &  referencePoint  ) const

private

Definition at line 49 of file TSCPBuilderNoMaterial.cc.

References createFTSatTransverseImpactPointCharged(), createFTSatTransverseImpactPointNeutral(), ExpressReco_HICollisions_FallBack::e, and FreeTrajectoryState::transverseCurvature().

Referenced by operator()().

{
  //
  // Straight line approximation? |rho|<1.e-10 equivalent to ~ 1um 
  // difference in transversal position at 10m.
  //
  if( fabs(originalFTS.transverseCurvature())<1.e-10 ) {
    return createFTSatTransverseImpactPointNeutral(originalFTS, referencePoint);
  } else {
    return createFTSatTransverseImpactPointCharged(originalFTS, referencePoint);
  }
}

TSCPBuilderNoMaterial::PairBoolFTS TSCPBuilderNoMaterial::createFTSatTransverseImpactPointCharged ( const FTS &  originalFTS, const GlobalPoint &  referencePoint  ) const

private

Definition at line 64 of file TSCPBuilderNoMaterial.cc.

References anyDirection, FreeTrajectoryState::charge(), FreeTrajectoryState::curvilinearError(), HelixBarrelPlaneCrossingByCircle::direction(), FreeTrajectoryState::hasError(), MagneticField::inInverseGeV(), AnalyticalCurvilinearJacobian::jacobian(), PV3DBase< T, PVType, FrameType >::mag(), GlobalTrajectoryParameters::magneticField(), CurvilinearTrajectoryError::matrix(), FreeTrajectoryState::momentum(), FreeTrajectoryState::parameters(), HelixBarrelPlaneCrossingByCircle::pathLength(), pos, HelixBarrelPlaneCrossingByCircle::position(), FreeTrajectoryState::position(), asciidump::s, FreeTrajectoryState::transverseCurvature(), Vector3DBase< T, FrameTag >::unit(), X, PV3DBase< T, PVType, FrameType >::x(), Basic3DVector< T >::x(), PV3DBase< T, PVType, FrameType >::y(), Basic3DVector< T >::y(), PV3DBase< T, PVType, FrameType >::z(), and Basic3DVector< T >::z().

Referenced by createFTSatTransverseImpactPoint().

{

  GlobalVector pvecOrig = originalFTS.momentum();
  GlobalPoint xvecOrig = originalFTS.position();
  double kappa = originalFTS.transverseCurvature();
  double pxOrig = pvecOrig.x();
  double pyOrig = pvecOrig.y();
  double pzOrig = pvecOrig.z();
  double xOrig = xvecOrig.x();
  double yOrig = xvecOrig.y();
  double zOrig = xvecOrig.z();

//  double fac = 1./originalFTS.charge()/MagneticField::inInverseGeV(referencePoint).z();
  double fac = 1./originalFTS.charge()/
    (originalFTS.parameters().magneticField().inInverseGeV(referencePoint).z());
  GlobalVectorDouble xOrig2Centre = GlobalVectorDouble(fac * pyOrig, -fac * pxOrig, 0.);
  GlobalVectorDouble xOrigProj = GlobalVectorDouble(xOrig, yOrig, 0.);
  GlobalVectorDouble xRefProj = GlobalVectorDouble(referencePoint.x(), referencePoint.y(), 0.);
  GlobalVectorDouble deltax = xRefProj-xOrigProj-xOrig2Centre;
  GlobalVectorDouble ndeltax = deltax.unit();

  PropagationDirection direction = anyDirection;
  Surface::PositionType pos(referencePoint);
  // Need to define plane with orientation as the
  // ImpactPointSurface
  GlobalVector X(ndeltax.x(), ndeltax.y(), ndeltax.z());
  GlobalVector Y(0.,0.,1.);
  Surface::RotationType rot(X,Y);
  BoundPlane* plane = new BoundPlane(pos,rot);
  // Using Teddy's HelixBarrelPlaneCrossingByCircle for general barrel planes. 
  // A large variety of other,
  // direct solutions turned out to be not so stable numerically.
  HelixBarrelPlaneCrossingByCircle 
    planeCrossing(HelixPlaneCrossing::PositionType(xOrig, yOrig, zOrig),
          HelixPlaneCrossing::DirectionType(pxOrig, pyOrig, pzOrig), 
          kappa, direction);
  std::pair<bool,double> propResult = planeCrossing.pathLength(*plane);
  if ( !propResult.first ) {
    edm::LogWarning ("TSCPBuilderNoMaterial") << "Propagation to perigee plane failed!";
    return PairBoolFTS(false, FreeTrajectoryState() );
  }
  double s = propResult.second;
  HelixPlaneCrossing::PositionType xGen = planeCrossing.position(s);
  GlobalPoint xPerigee = GlobalPoint(xGen.x(),xGen.y(),xGen.z());
  // direction (reconverted to GlobalVector, renormalised)
  HelixPlaneCrossing::DirectionType pGen = planeCrossing.direction(s);
  pGen *= pvecOrig.mag()/pGen.mag();
  GlobalVector pPerigee = GlobalVector(pGen.x(),pGen.y(),pGen.z());
  delete plane;
          
  if (originalFTS.hasError()) {
    const AlgebraicSymMatrix55 &errorMatrix = originalFTS.curvilinearError().matrix();
    AnalyticalCurvilinearJacobian curvilinJacobian(originalFTS.parameters(), xPerigee,
                           pPerigee, s);
    const AlgebraicMatrix55 &jacobian = curvilinJacobian.jacobian();
    CurvilinearTrajectoryError cte( ROOT::Math::Similarity(jacobian, errorMatrix) );
  
    return PairBoolFTS(true,
    FreeTrajectoryState(GlobalTrajectoryParameters(xPerigee, pPerigee, originalFTS.charge(), 
                &(originalFTS.parameters().magneticField())), cte) );
  } 
  else {
    return PairBoolFTS(true,
    FreeTrajectoryState(GlobalTrajectoryParameters(xPerigee, pPerigee, originalFTS.charge(), 
                &(originalFTS.parameters().magneticField()))) );
  }
  
}

TSCPBuilderNoMaterial::PairBoolFTS TSCPBuilderNoMaterial::createFTSatTransverseImpactPointNeutral ( const FTS &  originalFTS, const GlobalPoint &  referencePoint  ) const

private

Definition at line 137 of file TSCPBuilderNoMaterial.cc.

References FreeTrajectoryState::charge(), funct::cos(), FreeTrajectoryState::curvilinearError(), FreeTrajectoryState::hasError(), AnalyticalCurvilinearJacobian::jacobian(), GlobalTrajectoryParameters::magneticField(), CurvilinearTrajectoryError::matrix(), FreeTrajectoryState::momentum(), FreeTrajectoryState::parameters(), phi, PV3DBase< T, PVType, FrameType >::phi(), FreeTrajectoryState::position(), asciidump::s, funct::sin(), funct::tan(), PV3DBase< T, PVType, FrameType >::theta(), theta(), PV3DBase< T, PVType, FrameType >::x(), PV3DBase< T, PVType, FrameType >::y(), and PV3DBase< T, PVType, FrameType >::z().

Referenced by createFTSatTransverseImpactPoint().

{

  GlobalPoint xvecOrig = originalFTS.position();
  double phi = originalFTS.momentum().phi();
  double theta = originalFTS.momentum().theta();
  double xOrig = xvecOrig.x();
  double yOrig = xvecOrig.y();
  double zOrig = xvecOrig.z();
  double xR = referencePoint.x();
  double yR = referencePoint.y();

  double s2D = (xR - xOrig)  * cos(phi) + (yR - yOrig)  * sin(phi);
  double s = s2D / sin(theta);
  double xGen = xOrig + s2D*cos(phi);
  double yGen = yOrig + s2D*sin(phi);
  double zGen = zOrig + s2D/tan(theta);
  GlobalPoint xPerigee = GlobalPoint(xGen, yGen, zGen);

  GlobalVector pPerigee = originalFTS.momentum();
          
  if (originalFTS.hasError()) {
    const AlgebraicSymMatrix55 &errorMatrix = originalFTS.curvilinearError().matrix();
    AnalyticalCurvilinearJacobian curvilinJacobian(originalFTS.parameters(), xPerigee,
                           pPerigee, s);
    const AlgebraicMatrix55 &jacobian = curvilinJacobian.jacobian();
    CurvilinearTrajectoryError cte( ROOT::Math::Similarity(jacobian, errorMatrix) );
  
    return PairBoolFTS(true,
    FreeTrajectoryState(GlobalTrajectoryParameters(xPerigee, pPerigee, originalFTS.charge(), 
                &(originalFTS.parameters().magneticField())), cte));
  } 
  else {
    return PairBoolFTS(true,
    FreeTrajectoryState(GlobalTrajectoryParameters(xPerigee, pPerigee, originalFTS.charge(),
                &(originalFTS.parameters().magneticField()))) );
  }
  
}

TrajectoryStateClosestToPoint TSCPBuilderNoMaterial::operator() ( const FTS &  originalFTS, const GlobalPoint &  referencePoint  ) const

virtual

Implements TrajectoryStateClosestToPointBuilder.

Definition at line 13 of file TSCPBuilderNoMaterial.cc.

References TrajectoryStateClosestToPointBuilder::constructTSCP(), createFTSatTransverseImpactPoint(), FreeTrajectoryState::position(), and TrajectoryStateClosestToPointBuilder::positionEqual().

{
  if (positionEqual(referencePoint, originalFTS.position()))
    return constructTSCP(originalFTS, referencePoint);

  // Now do the propagation or whatever...

  PairBoolFTS newStatePair =
    createFTSatTransverseImpactPoint(originalFTS, referencePoint);
  if (newStatePair.first) {
    return constructTSCP(newStatePair.second, referencePoint);
  } else {
    return TrajectoryStateClosestToPoint();
  }  
}

TrajectoryStateClosestToPoint TSCPBuilderNoMaterial::operator() ( const TSOS &  originalTSOS, const GlobalPoint &  referencePoint  ) const

virtual

Implements TrajectoryStateClosestToPointBuilder.

Definition at line 31 of file TSCPBuilderNoMaterial.cc.

References TrajectoryStateClosestToPointBuilder::constructTSCP(), createFTSatTransverseImpactPoint(), TrajectoryStateOnSurface::freeState(), TrajectoryStateOnSurface::globalPosition(), and TrajectoryStateClosestToPointBuilder::positionEqual().

{
  if (positionEqual(referencePoint, originalTSOS.globalPosition()))
    return constructTSCP(*originalTSOS.freeState(), referencePoint);

  // Now do the propagation
  
  PairBoolFTS newStatePair =
    createFTSatTransverseImpactPoint(*originalTSOS.freeState(), referencePoint);
  if (newStatePair.first) {
    return constructTSCP(newStatePair.second, referencePoint);
  } else {
    return TrajectoryStateClosestToPoint();
  }
}