Acts::KalmanVertexUpdater Namespace Reference

Functions
void	updateTrackWithVertex (TrackAtVertex &track, const Vertex &vtx, unsigned int nDimVertex)
	Based on Ref.
void	updateVertexWithTrack (Vertex &vtx, TrackAtVertex &trk, unsigned int nDimVertex)
	KalmanVertexUpdater.

Function Documentation

updateTrackWithVertex()

void Acts::KalmanVertexUpdater::updateTrackWithVertex	(	TrackAtVertex &	track,
		const Vertex &	vtx,
		unsigned int	nDimVertex )

Based on Ref.

(1): R. Frühwirth et al. Vertex reconstruction and track bundling at the lep collider using robust algorithms Computer Physics Comm.: 96 (1996) 189 Chapter 2.1

Refits a single track with the knowledge of the vertex it has originated from

Parameters

track	Track to update
vtx	Vertex to use for updating the track
nDimVertex	number of dimensions of the vertex. Can be 3 (if we only fit its spatial coordinates) or 4 (if we also fit time).

updateVertexWithTrack()

void Acts::KalmanVertexUpdater::updateVertexWithTrack	(	Vertex &	vtx,
		TrackAtVertex &	trk,
		unsigned int	nDimVertex )

KalmanVertexUpdater.

adds or removes track from or updates current vertex Based on Ref. (1): R. Frühwirth et al. Vertex reconstruction and track bundling at the lep collider using robust algorithms Computer Physics Comm.: 96 (1996) 189 Chapter 2.1

For remarks on the weighted formalism, which we use here, see Ref. (2): Giacinto Piacquadio Identification of b-jets and investigation of the discovery potential of a Higgs boson in the WH−−>lvbb¯ channel with the ATLAS experiment CERN-THESIS-2010-027 Section 5.3.5

Updates vertex with knowledge of new track

Note

KalmanVertexUpdater updates the vertex when trk is added to the fit. However, it does not add the track to the TrackAtVertex list. This to be done manually after calling the method.

Parameters

vtx	Vertex to be updated
trk	Track to be used for updating the vertex
nDimVertex	number of dimensions of the vertex. Can be 3 (if we only fit its spatial coordinates) or 4 (if we also fit time).