#include <IVertexLinearizedTrackFactory.h>

Inheritance diagram for Trk::IVertexLinearizedTrackFactory:

Collaboration diagram for Trk::IVertexLinearizedTrackFactory:

Public Member Functions
virtual	~IVertexLinearizedTrackFactory ()
	Virtual destructor. More...

virtual void	linearize (VxTrackAtVertex &theTrack, const Amg::Vector3D &linPoint) const =0
	Interface for Trk::VxTrackAtVertex: Takes a Trk::TrackParameters from Trk::VxTrackAtVertex and a lineariztion point. More...

virtual LinearizedTrack *	linearizedTrack (const TrackParameters *perigee, const Amg::Vector3D &linPoint) const =0
	Linearization method: Takes a Trk::TrackParameters and a linearization point. More...

virtual LinearizedTrack *	linearizedTrack (const NeutralParameters *perigee, const Amg::Vector3D &linPoint) const =0
	Linearization method: Takes a Trk::NeutralParameters and a linearization point. More...

Static Public Member Functions
static const InterfaceID &	interfaceID ()
	AlgTool interface methods. More...

Detailed Description

An Abstract Base Class for the LinearizedTrackFactories. Aim: Linearizes the measurement equation (dependance of track parameters on the vertex position and track mometum at vertex) at the vicinity of the user-provided linearization point.

The measurement equation is linearized in the following way:

q_k= A_k (x_k - x_0k) + B_k (p_k - p_0k) + c_k

where q_k are the parameters at perigee nearest to the lin point, x_k is the position of the vertex, p_k the track momentum at the vertex, and c_k is the constant term of expansion. A_k and B_k are matrices of derivatives, denoted hereafter as "positionJacobian" and "momentumJacobian" respectively.

Result of the calculation is stored in the object of type TrkEvent/VxVertex/PerigeeLinearizedTrack. Due to the present EDM structure, the current implementation of
this class supports only the perigee parametrization of the track. Extension for the arbitrary track parametrization is foreseen.