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TSCPBuilderNoMaterial Class Reference

This class builds a TrajectoryStateClosestToPoint given an original TrajectoryStateOnSurface or FreeTrajectoryState. More...

#include <TrackingTools/PatternTools/interface/TSCPBuilderNoMaterial.h>

Inheritance diagram for TSCPBuilderNoMaterial:

TrajectoryStateClosestToPointBuilder

List of all members.

Public Member Functions

virtual
TrajectoryStateClosestToPoint 		operator() (const TSOS &originalTSOS, const GlobalPoint &referencePoint) const
virtual
TrajectoryStateClosestToPoint 		operator() (const FTS &originalFTS, const GlobalPoint &referencePoint) const
virtual ~TSCPBuilderNoMaterial ()

Private Types

typedef Point3DBase< double,
GlobalTag > 		GlobalPointDouble
typedef Vector3DBase< double,
GlobalTag > 		GlobalVectorDouble

Private Member Functions

FreeTrajectoryState createFTSatTransverseImpactPoint (const FTS &originalFTS, const GlobalPoint &referencePoint) const
FreeTrajectoryState createFTSatTransverseImpactPointCharged (const FTS &originalFTS, const GlobalPoint &referencePoint) const
FreeTrajectoryState createFTSatTransverseImpactPointNeutral (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.

Definition at line 15 of file TSCPBuilderNoMaterial.h.

Member Typedef Documentation

typedef Point3DBase< double, GlobalTag> TSCPBuilderNoMaterial::GlobalPointDouble [private]

Definition at line 30 of file TSCPBuilderNoMaterial.h.

typedef Vector3DBase< double, GlobalTag> TSCPBuilderNoMaterial::GlobalVectorDouble [private]

Definition at line 31 of file TSCPBuilderNoMaterial.h.

Constructor & Destructor Documentation

virtual TSCPBuilderNoMaterial::~TSCPBuilderNoMaterial (  )  [inline, virtual]

Definition at line 20 of file TSCPBuilderNoMaterial.h.

00020 {}

Member Function Documentation

FreeTrajectoryState TSCPBuilderNoMaterial::createFTSatTransverseImpactPoint ( const FTS &  originalFTS,
const GlobalPoint &  referencePoint 
) const [private]

Definition at line 41 of file TSCPBuilderNoMaterial.cc.

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

Referenced by operator()().

00043 {
00044   //
00045   // Straight line approximation? |rho|<1.e-10 equivalent to ~ 1um 
00046   // difference in transversal position at 10m.
00047   //
00048   if( fabs(originalFTS.transverseCurvature())<1.e-10 ) {
00049     return createFTSatTransverseImpactPointNeutral(originalFTS, referencePoint);
00050   } else {
00051     return createFTSatTransverseImpactPointCharged(originalFTS, referencePoint);
00052   }
00053 }

FreeTrajectoryState TSCPBuilderNoMaterial::createFTSatTransverseImpactPointCharged ( const FTS &  originalFTS,
const GlobalPoint &  referencePoint 
) const [private]

Definition at line 56 of file TSCPBuilderNoMaterial.cc.

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

Referenced by createFTSatTransverseImpactPoint().

00058 {
00059 
00060   GlobalVector pvecOrig = originalFTS.momentum();
00061   GlobalPoint xvecOrig = originalFTS.position();
00062   double kappa = originalFTS.transverseCurvature();
00063   double pxOrig = pvecOrig.x();
00064   double pyOrig = pvecOrig.y();
00065   double pzOrig = pvecOrig.z();
00066   double xOrig = xvecOrig.x();
00067   double yOrig = xvecOrig.y();
00068   double zOrig = xvecOrig.z();
00069 
00070 //  double fac = 1./originalFTS.charge()/MagneticField::inInverseGeV(referencePoint).z();
00071   double fac = 1./originalFTS.charge()/
00072     (originalFTS.parameters().magneticField().inInverseGeV(referencePoint).z());
00073   GlobalVectorDouble xOrig2Centre = GlobalVectorDouble(fac * pyOrig, -fac * pxOrig, 0.);
00074   GlobalVectorDouble xOrigProj = GlobalVectorDouble(xOrig, yOrig, 0.);
00075   GlobalVectorDouble xRefProj = GlobalVectorDouble(referencePoint.x(), referencePoint.y(), 0.);
00076   GlobalVectorDouble deltax = xRefProj-xOrigProj-xOrig2Centre;
00077   GlobalVectorDouble ndeltax = deltax.unit();
00078 
00079   PropagationDirection direction = anyDirection;
00080   Surface::PositionType pos(referencePoint);
00081   // Need to define plane with orientation as the
00082   // ImpactPointSurface
00083   GlobalVector X(ndeltax.x(), ndeltax.y(), ndeltax.z());
00084   GlobalVector Y(0.,0.,1.);
00085   Surface::RotationType rot(X,Y);
00086   BoundPlane* plane = new BoundPlane(pos,rot);
00087   // Using Teddy's HelixBarrelPlaneCrossingByCircle for general barrel planes. 
00088   // A large variety of other,
00089   // direct solutions turned out to be not so stable numerically.
00090   HelixBarrelPlaneCrossingByCircle 
00091     planeCrossing(HelixPlaneCrossing::PositionType(xOrig, yOrig, zOrig),
00092                   HelixPlaneCrossing::DirectionType(pxOrig, pyOrig, pzOrig), 
00093                   kappa, direction);
00094   std::pair<bool,double> propResult = planeCrossing.pathLength(*plane);
00095   if ( !propResult.first ) 
00096     throw TrajectoryStateException("Propagation to perigee plane failed!");
00097   double s = propResult.second;
00098   HelixPlaneCrossing::PositionType xGen = planeCrossing.position(s);
00099   GlobalPoint xPerigee = GlobalPoint(xGen.x(),xGen.y(),xGen.z());
00100   // direction (reconverted to GlobalVector, renormalised)
00101   HelixPlaneCrossing::DirectionType pGen = planeCrossing.direction(s);
00102   pGen *= pvecOrig.mag()/pGen.mag();
00103   GlobalVector pPerigee = GlobalVector(pGen.x(),pGen.y(),pGen.z());
00104   delete plane;
00105                   
00106   if (originalFTS.hasError()) {
00107     const AlgebraicSymMatrix55 &errorMatrix = originalFTS.curvilinearError().matrix();
00108     AnalyticalCurvilinearJacobian curvilinJacobian(originalFTS.parameters(), xPerigee,
00109                                                    pPerigee, s);
00110     const AlgebraicMatrix55 &jacobian = curvilinJacobian.jacobian();
00111     CurvilinearTrajectoryError cte( ROOT::Math::Similarity(jacobian, errorMatrix) );
00112   
00113     return FreeTrajectoryState(GlobalTrajectoryParameters(xPerigee, pPerigee, originalFTS.charge(), 
00114                                         &(originalFTS.parameters().magneticField())),
00115                                 cte);
00116   } 
00117   else {
00118     return FreeTrajectoryState(GlobalTrajectoryParameters(xPerigee, pPerigee, originalFTS.charge(), 
00119                                         &(originalFTS.parameters().magneticField())));
00120   }
00121   
00122 }

FreeTrajectoryState TSCPBuilderNoMaterial::createFTSatTransverseImpactPointNeutral ( const FTS &  originalFTS,
const GlobalPoint &  referencePoint 
) const [private]

Definition at line 126 of file TSCPBuilderNoMaterial.cc.

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

Referenced by createFTSatTransverseImpactPoint().

00128 {
00129 
00130   GlobalPoint xvecOrig = originalFTS.position();
00131   double phi = originalFTS.momentum().phi();
00132   double theta = originalFTS.momentum().theta();
00133   double xOrig = xvecOrig.x();
00134   double yOrig = xvecOrig.y();
00135   double zOrig = xvecOrig.z();
00136   double xR = referencePoint.x();
00137   double yR = referencePoint.y();
00138 
00139   double s2D = (xR - xOrig)  * cos(phi) + (yR - yOrig)  * sin(phi);
00140   double s = s2D / sin(theta);
00141   double xGen = xOrig + s2D*cos(phi);
00142   double yGen = yOrig + s2D*sin(phi);
00143   double zGen = zOrig + s2D/tan(theta);
00144   GlobalPoint xPerigee = GlobalPoint(xGen, yGen, zGen);
00145 
00146   GlobalVector pPerigee = originalFTS.momentum();
00147                   
00148   if (originalFTS.hasError()) {
00149     const AlgebraicSymMatrix55 &errorMatrix = originalFTS.curvilinearError().matrix();
00150     AnalyticalCurvilinearJacobian curvilinJacobian(originalFTS.parameters(), xPerigee,
00151                                                    pPerigee, s);
00152     const AlgebraicMatrix55 &jacobian = curvilinJacobian.jacobian();
00153     CurvilinearTrajectoryError cte( ROOT::Math::Similarity(jacobian, errorMatrix) );
00154   
00155     return FreeTrajectoryState(GlobalTrajectoryParameters(xPerigee, pPerigee, originalFTS.charge(), 
00156                                         &(originalFTS.parameters().magneticField())),
00157                                 cte);
00158   } 
00159   else {
00160     return FreeTrajectoryState(GlobalTrajectoryParameters(xPerigee, pPerigee, originalFTS.charge(),
00161                                         &(originalFTS.parameters().magneticField())));
00162   }
00163   
00164 }

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

Implements TrajectoryStateClosestToPointBuilder.

Definition at line 27 of file TSCPBuilderNoMaterial.cc.

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

00029 {
00030   if (positionEqual(referencePoint, originalTSOS.globalPosition()))
00031     return constructTSCP(*originalTSOS.freeState(), referencePoint);
00032 
00033   // Now do the propagation
00034   
00035   FreeTrajectoryState ftsAtTransverseImpactPoint = 
00036     createFTSatTransverseImpactPoint(*originalTSOS.freeState(), referencePoint);
00037   return constructTSCP(ftsAtTransverseImpactPoint, referencePoint);
00038 }

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

Implements TrajectoryStateClosestToPointBuilder.

Definition at line 12 of file TSCPBuilderNoMaterial.cc.

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

00014 {
00015   if (positionEqual(referencePoint, originalFTS.position()))
00016     return constructTSCP(originalFTS, referencePoint);
00017 
00018   // Now do the propagation or whatever...
00019 
00020   FreeTrajectoryState 
00021     ftsAtTransverseImpactPoint = createFTSatTransverseImpactPoint(originalFTS, referencePoint);
00022   return constructTSCP(ftsAtTransverseImpactPoint, referencePoint);
00023   
00024 }

The documentation for this class was generated from the following files:
Generated on Tue Jun 9 18:34:37 2009 for CMSSW by  doxygen 1.5.4