Acts::HelicalTrackLinearizer< propagator_t, propagator_options_t > Class Template Reference

#include <acts/blob/master/Core/include/Acts/Vertexing/HelicalTrackLinearizer.hpp>

Collaboration diagram for Acts::HelicalTrackLinearizer< propagator_t, propagator_options_t >:

Classes
struct	Config
	Configuration struct. More...

Public Types
using	Propagator_t = propagator_t
using	BField_t = typename Propagator_t::Stepper::BField

Public Member Functions
	HelicalTrackLinearizer (const Config &config)
	Constructor.
Result< LinearizedTrack >	linearizeTrack (const BoundParameters &params, const SpacePointVector &linPoint, const Acts::GeometryContext &gctx, const Acts::MagneticFieldContext &mctx) const
	Function that linearizes BoundParameters at given linearization point.

Private Attributes
const Config	m_cfg
	Configuration object.

Detailed Description

template<typename propagator_t, typename propagator_options_t = PropagatorOptions<>>
class Acts::HelicalTrackLinearizer< propagator_t, propagator_options_t >

Linearizes the measurement equation (dependance of track parameters on the vertex position and track momentum 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.

Ref.(1) - CERN-THESIS-2010-027, Giacinto Piacquadio (Freiburg U.)

Template Parameters

propagator_t	Propagator type
propagator_options_t	Propagator options type

Definition at line 44 of file HelicalTrackLinearizer.hpp.

View newest version in sPHENIX GitHub at line 44 of file HelicalTrackLinearizer.hpp

Member Typedef Documentation

template<typename propagator_t , typename propagator_options_t = PropagatorOptions<>>

using Acts::HelicalTrackLinearizer< propagator_t, propagator_options_t >::BField_t = typename Propagator_t::Stepper::BField

Definition at line 47 of file HelicalTrackLinearizer.hpp.

View newest version in sPHENIX GitHub at line 47 of file HelicalTrackLinearizer.hpp

template<typename propagator_t , typename propagator_options_t = PropagatorOptions<>>

using Acts::HelicalTrackLinearizer< propagator_t, propagator_options_t >::Propagator_t = propagator_t

Definition at line 46 of file HelicalTrackLinearizer.hpp.

View newest version in sPHENIX GitHub at line 46 of file HelicalTrackLinearizer.hpp

Constructor & Destructor Documentation

template<typename propagator_t , typename propagator_options_t = PropagatorOptions<>>

Acts::HelicalTrackLinearizer< propagator_t, propagator_options_t >::HelicalTrackLinearizer ( const Config &  config )

inline

Constructor.

Parameters

config

Configuration object

Definition at line 80 of file HelicalTrackLinearizer.hpp.

View newest version in sPHENIX GitHub at line 80 of file HelicalTrackLinearizer.hpp

Member Function Documentation

template<typename propagator_t , typename propagator_options_t >

Acts::Result< Acts::LinearizedTrack > Acts::HelicalTrackLinearizer< propagator_t, propagator_options_t >::linearizeTrack	(	const BoundParameters &	params,
		const SpacePointVector &	linPoint,
		const Acts::GeometryContext &	gctx,
		const Acts::MagneticFieldContext &	mctx
	)		const

Function that linearizes BoundParameters at given linearization point.

Parameters

params	Parameters to linearize
linPoint	Linearization point
gctx	The geometry context
mctx	The magnetic field context

Returns

Linearized track

F(V, p_i) at PCA in Billoir paper (see FullBilloirVertexFitter.hpp for paper reference, Page 140, Eq. (2) )

Definition at line 13 of file HelicalTrackLinearizer.ipp.

View newest version in sPHENIX GitHub at line 13 of file HelicalTrackLinearizer.ipp

References kdfinder::abs(), Acts::backward, Acts::IntegrationTest::Bz, Acts::SingleTrackParameters< ChargePolicy >::covariance(), Acts::ePHI, Acts::eQOP, Acts::eTHETA, Acts::eZ, Acts::SingleTrackParameters< ChargePolicy >::get(), M_PI, Acts::SingleTrackParameters< ChargePolicy >::parameters(), Acts::SingleTrackParameters< ChargePolicy >::position(), position, Q, Acts::IntegrationTest::R, S(), X, and Y.

Referenced by Acts::Test::BOOST_AUTO_TEST_CASE().

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Member Data Documentation

template<typename propagator_t , typename propagator_options_t = PropagatorOptions<>>

const Config Acts::HelicalTrackLinearizer< propagator_t, propagator_options_t >::m_cfg

private

Configuration object.

Definition at line 98 of file HelicalTrackLinearizer.hpp.

View newest version in sPHENIX GitHub at line 98 of file HelicalTrackLinearizer.hpp

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The documentation for this class was generated from the following files:

• acts/blob/master/Core/include/Acts/Vertexing/HelicalTrackLinearizer.hpp
• acts/blob/master/Core/include/Acts/Vertexing/HelicalTrackLinearizer.ipp