#include <PropagateToCal.h>

Public Member Functions
bool	propagate (const GlobalPoint &vertex, GlobalVector &Cand, int charge, const MagneticField *bField) const
	PropagateToCal ()
	PropagateToCal (double radius, double minZ, double maxZ, bool theIgnoreMaterial)
	~PropagateToCal ()
Private Attributes
double	maxZ_
double	minZ_
double	radius_
	whether or not propagation should ignore material
bool	theIgnoreMaterial_

Detailed Description

Definition at line 26 of file PropagateToCal.h.

Constructor & Destructor Documentation

PropagateToCal::PropagateToCal ( )

PropagateToCal::~PropagateToCal ( )

Definition at line 18 of file PropagateToCal.cc.

{
}

PropagateToCal::PropagateToCal	(	double	radius,
		double	minZ,
		double	maxZ,
		bool	theIgnoreMaterial
	)

Definition at line 3 of file PropagateToCal.cc.

References Exception, CosmicsPD_Skims::maxZ, maxZ_, cmsRun_displayProdMFGeom_cfg::minZ, minZ_, CosmicsPD_Skims::radius, radius_, and theIgnoreMaterial_.

{ 
  radius_ = radius; 
  maxZ_ = maxZ; 
  minZ_ = minZ; 
  theIgnoreMaterial_ = theIgnoreMaterial;
  if (maxZ_ < minZ_ || radius < 0.0) 
    throw cms::Exception("BadConfig") << "PropagateToCal: CalMaxZ (" 
                                      << maxZ_
                                      << ") smaller than CalMinZ (" 
                                      << minZ_ << ") or invalid radius ("
                                      << radius_ << ").";
}

Member Function Documentation

bool PropagateToCal::propagate	(	const GlobalPoint &	vertex,
		GlobalVector &	Cand,
		int	charge,
		const MagneticField *	bField
	)		const

the code is inspired by Gero's CosmicGenFilterHelix class:

target cylinder, around z-axis

plane closing cylinder at 'negative' side

plane closing cylinder at 'positive' side

The result is the vector connecting the extrapolation endPoint on the Calorimeter surface and the origin of the coordinate system, point (0,0,0).

Successfully propagated to the calorimeter or not

Definition at line 23 of file PropagateToCal.cc.

References newFWLiteAna::build, maxZ_, minZ_, SteppingHelixPropagator::propagateWithPath(), LargeD0_PixelPairStep_cff::propagator, radius_, query::result, SteppingHelixPropagator::setMaterialMode(), SteppingHelixPropagator::setNoErrorPropagation(), and theIgnoreMaterial_.

{
  bool result = true;
  typedef std::pair<TrajectoryStateOnSurface, double> TsosPath;

  SteppingHelixPropagator propagator(field); // should we somehow take it from ESetup???
  propagator.setMaterialMode(theIgnoreMaterial_); // no material effects if set to true
  propagator.setNoErrorPropagation(true);

  const FreeTrajectoryState fts(GlobalTrajectoryParameters(vertex, Cand, charge, field));
  const Surface::RotationType dummyRot;

  Cylinder::ConstCylinderPointer theTargetCylinder = 
    Cylinder::build(Surface::PositionType(0.,0.,0.), dummyRot, radius_);

  Plane::ConstPlanePointer theTargetPlaneMin = 
    Plane::build(Surface::PositionType(0.,0.,minZ_), dummyRot);

  Plane::ConstPlanePointer theTargetPlaneMax = 
    Plane::build(Surface::PositionType(0.,0.,maxZ_), dummyRot);

  TsosPath aTsosPath(propagator.propagateWithPath(fts, *theTargetCylinder));
  if (!aTsosPath.first.isValid()) {
    result = false;
  } else if (aTsosPath.first.globalPosition().z() < theTargetPlaneMin->position().z()) {
    // If on cylinder, but outside minimum z, try minimum z-plane:
    // (Would it be possible to miss rdius on plane, but reach cylinder afterwards in z-range?
    //  No, at least not in B-field parallel to z-axis which is cylinder axis.)
    aTsosPath = propagator.propagateWithPath(fts, *theTargetPlaneMin);
    if (!aTsosPath.first.isValid()
        || aTsosPath.first.globalPosition().perp() > theTargetCylinder->radius()) {
      result = false;
    }
  } else if (aTsosPath.first.globalPosition().z() > theTargetPlaneMax->position().z()) {
    // Analog for outside maximum z:
    aTsosPath = propagator.propagateWithPath(fts, *theTargetPlaneMax);
    if (!aTsosPath.first.isValid()
        || aTsosPath.first.globalPosition().perp() > theTargetCylinder->radius()) {
      result = false;
    }
  }
  if (result) {
    Cand = GlobalVector(aTsosPath.first.globalPosition().x(),
                        aTsosPath.first.globalPosition().y(),
                        aTsosPath.first.globalPosition().z() );
  }
  return result;
}