PixelTrackBuilder Class Reference

#include <PixelTrackBuilder.h>

Public Member Functions
reco::Track *	build (const Measurement1D &pt, const Measurement1D &phi, const Measurement1D &cotTheta, const Measurement1D &tip, const Measurement1D &zip, float chi2, int charge, const std::vector< const TrackingRecHit * > &hits, const MagneticField *mf, const GlobalPoint &reference=GlobalPoint(0, 0, 0)) const

Detailed Description

Definition at line 13 of file PixelTrackBuilder.h.

Member Function Documentation

reco::Track * PixelTrackBuilder::build	(	const Measurement1D &	pt,
		const Measurement1D &	phi,
		const Measurement1D &	cotTheta,
		const Measurement1D &	tip,
		const Measurement1D &	zip,
		float	chi2,
		int	charge,
		const std::vector< const TrackingRecHit * > &	hits,
		const MagneticField *	mf,
		const GlobalPoint &	reference = GlobalPoint(0, 0, 0)
	)		const

Definition at line 123 of file PixelTrackBuilder.cc.

References BasicReferenceCounted::addReference(), BasicTrajectoryState::charge(), funct::cos(), CommonMethods::cp(), BasicTrajectoryState::curvilinearError(), Measurement1D::error(), relativeConstraints::error, BasicTrajectoryState::globalMomentum(), BasicTrajectoryState::globalPosition(), LogDebug, LogTrace, visualization-live-secondInstance_cfg::m, ndof, createTree::pp, print(), makeMuonMisalignmentScenario::rot, funct::sin(), sqr(), mathSSE::sqrt(), HLT_FULL_cff::track, Measurement1D::value(), PV3DBase< T, PVType, FrameType >::x(), PV3DBase< T, PVType, FrameType >::y(), and PV3DBase< T, PVType, FrameType >::z().

Referenced by PixelFitterByConformalMappingAndLine::run(), PixelFitterByHelixProjections::run(), TrackFitter::run(), and L1MuonPixelTrackFitter::run().

                                                                       {
  LogDebug("PixelTrackBuilder::build") << "";
  LogTrace("") << "Reconstructed triplet kinematics: " << print(pt, phi, cotTheta, tip, zip, chi2, charge);

  double sinTheta = 1 / std::sqrt(1 + sqr(cotTheta.value()));
  double cosTheta = cotTheta.value() * sinTheta;
  int tipSign = tip.value() > 0 ? 1 : -1;

  AlgebraicSymMatrix55 m;
  double invPtErr = 1. / sqr(pt.value()) * pt.error();
  m(0, 0) = sqr(sinTheta) * (sqr(invPtErr) + sqr(cotTheta.error() / pt.value() * cosTheta * sinTheta));
  m(0, 2) = sqr(cotTheta.error()) * cosTheta * sqr(sinTheta) / pt.value();
  m(1, 1) = sqr(phi.error());
  m(2, 2) = sqr(cotTheta.error());
  m(3, 3) = sqr(tip.error());
  m(4, 4) = sqr(zip.error());
  LocalTrajectoryError error(m);

  LocalTrajectoryParameters lpar(LocalPoint(tipSign * tip.value(), -tipSign * zip.value(), 0),
                                 LocalVector(0., -tipSign * pt.value() * cotTheta.value(), pt.value()),
                                 charge);

  float sp = std::sin(phi.value());
  float cp = std::cos(phi.value());
  Surface::RotationType rot(sp * tipSign, -cp * tipSign, 0, 0, 0, -tipSign, cp, sp, 0);

  // BTSOS hold Surface in a shared pointer and  will be autodeleted when BTSOS goes out of scope...
  // to avoid memory churn we allocate it locally and just avoid it be deleted by refcount...
  Plane impPointPlane(origin, rot);
  // (twice just to be sure!)
  impPointPlane.addReference();
  impPointPlane.addReference();
  // use Base (to avoid a useless new)
  BasicTrajectoryStateOnSurface impactPointState(lpar, error, impPointPlane, mf);

#ifdef DEBUG_STATE
  checkState(impactPointState, mf);
#endif
  LogTrace("") << "constructed TSOS:\n" << print(impactPointState);

  int ndof = 2 * hits.size() - 5;
  GlobalPoint vv = impactPointState.globalPosition();
  math::XYZPoint pos(vv.x(), vv.y(), vv.z());
  GlobalVector pp = impactPointState.globalMomentum();
  math::XYZVector mom(pp.x(), pp.y(), pp.z());

  reco::Track* track =
      new reco::Track(chi2, ndof, pos, mom, impactPointState.charge(), impactPointState.curvilinearError());

  return track;
}