Improved V0 fitter class. More...

#include <NewV0Fitter.h>

Collaboration diagram for NewV0Fitter:

[legend]

Classes
struct	FittedTrack
	Structure to save track data of the last successful iteration. More...

Public Member Functions
	NewV0Fitter (const std::string &trackFitResultsName="", const std::string &v0sName="", const std::string &v0ValidationVerticesName="", const std::string &recoTracksName="", const std::string &copiedRecoTracksName="CopiedRecoTracks", bool enableValidation=false)
	Constructor. More...

void	initializeCuts (double vertexDistanceCut, double vertexChi2Cut, const std::tuple< double, double > &invMassRangeKshort, const std::tuple< double, double > &invMassRangeLambda, const std::tuple< double, double > &invMassRangePhoton)
	Initialization of cuts applied during the fit and store process. More...

void	setFitterMode (int fitterMode)
	Setter for the fitter mode. More...

bool	fitAndStore (const Track trackPlus, const Track trackMinus, const Const::ParticleType &v0Hypothesis, bool &isForceStored, bool &isHitRemoved)
	Fit V0 with given hypothesis and store results if fit is successful. More...

Static Public Member Functions
static std::pair< Const::ParticleType, Const::ParticleType >	getTrackHypotheses (const Const::ParticleType &v0Hypothesis)
	Returns daughter particle types for a given V0 hypothesis. More...

Private Types
enum	ErrorStatus { c_NoTrackRepresentation = -4 , c_VertexFitFailed = -3 , c_ExtrapolationFailed = -2 , c_NotSelected = -1 }
	Error status codes returned by the vertexFit method. More...

enum	EInnerHitBits { c_BitTrackPlus = 0x1 , c_BitTrackMinus = 0x2 }
	Bits used to signal that track has hits inside the V0 vertex. More...

Private Member Functions
int	vertexFit (const RecoTrack recoTrackPlus, const RecoTrack recoTrackMinus, int pdgTrackPlus, int pdgTrackMinus, const Const::ParticleType &v0Hypothesis)
	Performs a vertex fit. More...

const genfit::AbsTrackRep *	getTrackRepresentation (const RecoTrack *recoTrack, int pdgCode)
	Returns track representation for a given PDG code. More...

bool	setCardinalRep (genfit::Track &gfTrack, int pdgCode)
	Sets cardinal representation of a given genfit track and PDG code. More...

bool	fitGFRaveVertex (genfit::Track &trackPlus, genfit::Track &trackMinus, genfit::GFRaveVertex &vertex)
	Genfit Rave vertex fit called by vertexFit method. More...

int	extrapolateToVertex (genfit::MeasuredStateOnPlane &statePlus, genfit::MeasuredStateOnPlane &stateMinus, const genfit::GFRaveVertex &vertex)
	Extrapolation of both tracks to the vertex. More...

RecoTrack *	copyRecoTrack (const RecoTrack *origRecoTrack, const genfit::MeasuredStateOnPlane &state)
	Make a copy of reco track. More...

const RecoTrack *	removeHitsAndRefit (const RecoTrack origRecoTrack, const RecoTrack lastRecoTrack, const Const::ParticleType &ptype)
	Remove track inner hits and refit the track. More...

int	isInnermostClusterShared (const RecoTrack recoTrackPlus, const RecoTrack recoTrackMinus)
	Returns bit flags indicating that the innermost cluster is shared between both tracks. More...

const TrackFitResult *	saveTrackFitResult (const FittedTrack &trk, int sharedInnermostCluster)
	Append track fit result to the collection. More...

Private Attributes
std::string	m_recoTracksName
	name of the RecoTracks collection

StoreArray< RecoTrack >	m_recoTracks
	RecoTracks collection.

StoreArray< TrackFitResult >	m_trackFitResults
	TrackFitResults collection.

StoreArray< V0 >	m_v0s
	V0s collection.

StoreArray< V0ValidationVertex >	m_validationV0s
	V0ValidationVertex collection (optional)

StoreArray< RecoTrack >	m_copiedRecoTracks
	copied RecoTracks collection

double	m_vertexDistanceCut = 0
	cut on the transverse radius

double	m_vertexChi2Cut = 0
	Chi2 cut.

std::map< int, std::pair< double, double > >	m_invMassCuts
	invariant mass cuts, key = abs(PDG)

int	m_fitterMode = 1
	fitter mode

bool	m_validation = false
	validation flag

genfit::GFRaveVertex	m_fittedVertex
	last successfully fitted vertex

double	m_momentum = 0
	momentum of last successfully fitted vertex

double	m_invMass = 0
	invariant mass of last successfully fitted vertex

FittedTrack	m_trkPlus
	positively charged track data of last successfully fitted vertex

FittedTrack	m_trkMinus
	negatively charged track data of last successfully fitted vertex

Detailed Description

Improved V0 fitter class.

Definition at line 30 of file NewV0Fitter.h.

Member Enumeration Documentation

◆ EInnerHitBits

enum EInnerHitBits

private

Bits used to signal that track has hits inside the V0 vertex.

Enumerator
c_BitTrackPlus	positive track has inner hits
c_BitTrackMinus	negative track has inner hits

Definition at line 139 of file NewV0Fitter.h.

                        {
       c_BitTrackPlus = 0x1, 
       c_BitTrackMinus = 0x2 
     };

◆ ErrorStatus

enum ErrorStatus

private

Error status codes returned by the vertexFit method.

Enumerator
c_NoTrackRepresentation	no track representation for given PDG code
c_VertexFitFailed	vertex fit failed
c_ExtrapolationFailed	track extrapolation failed
c_NotSelected	fitted vertex not passing the cuts

Definition at line 128 of file NewV0Fitter.h.

Constructor & Destructor Documentation

◆ NewV0Fitter()

NewV0Fitter	(	const std::string &	trackFitResultsName = `""`,
		const std::string &	v0sName = `""`,
		const std::string &	v0ValidationVerticesName = `""`,
		const std::string &	recoTracksName = `""`,
		const std::string &	copiedRecoTracksName = `"CopiedRecoTracks"`,
		bool	enableValidation = `false`
	)

Constructor.

Parameters

trackFitResultsName	name of the StoreArray TrackFitResults
v0sName	name of the StoreArray V0s
v0ValidationVerticesName	name of the StoreArray V0ValidationVertex
recoTracksName	name of the StoreArray RecoTracks
copiedRecoTracksName	name of the StoreArray of copied RecoTracks
enableValidation	on true store additional data for validation

Definition at line 27 of file NewV0Fitter.cc.

   : m_recoTracksName(recoTracksName), m_validation(enableValidation)
 {
   B2ASSERT("V0Fitter: material effects not set up.  Please use SetupGenfitExtrapolationModule.",
            genfit::MaterialEffects::getInstance()->isInitialized());
   B2ASSERT("V0Fitter: magnetic field not set up.  Please use SetupGenfitExtrapolationModule.",
            genfit::FieldManager::getInstance()->isInitialized());
  
   m_recoTracks.isRequired(m_recoTracksName);
   m_trackFitResults.isRequired(trackFitResultsName);
  
   m_v0s.registerInDataStore(v0sName, DataStore::c_WriteOut | DataStore::c_ErrorIfAlreadyRegistered);
   m_copiedRecoTracks.registerInDataStore(copiedRecoTracksName, DataStore::c_ErrorIfAlreadyRegistered);
   RecoTrack::registerRequiredRelations(m_copiedRecoTracks);
   m_copiedRecoTracks.registerRelationTo(m_recoTracks);
  
   if (m_validation) {
     m_validationV0s.registerInDataStore(v0ValidationVerticesName, DataStore::c_ErrorIfAlreadyRegistered);
     m_v0s.registerRelationTo(m_validationV0s);
   }
  
 }

Member Function Documentation

◆ copyRecoTrack()

RecoTrack * copyRecoTrack	(	const RecoTrack *	origRecoTrack,
		const genfit::MeasuredStateOnPlane &	state
	)

private

Make a copy of reco track.

Parameters

origRecoTrack	source
state	measured state for the track fit seeding

Returns: a copy of source

Definition at line 396 of file NewV0Fitter.cc.

◆ extrapolateToVertex()

int extrapolateToVertex	(	genfit::MeasuredStateOnPlane &	statePlus,
		genfit::MeasuredStateOnPlane &	stateMinus,
		const genfit::GFRaveVertex &	vertex
	)

private

Extrapolation of both tracks to the vertex.

On success the return value indicates if tracks have inner hits (see EInnerHitBits).

Parameters

statePlus	measured state of positively charged track from which the extrapolation is performed [in/out]
stateMinus	measured state of negatively charged track from which the extrapolation is performed [in/out]
vertex	vertex

Returns: value >= 0 on success, value < 0 on failure

extrapolate the first (innermost) hit to the V0 vertex position the value will be positive (negative) if the direction of the extrapolation is (counter)momentum-wise

plus track has hits inside the V0 vertex.

minus track has hits inside the V0 vertex.

This shouldn't ever happen, but I can see the extrapolation code trying several windings before giving up, so this happens occasionally. Something more stable would perhaps be desirable.

Definition at line 286 of file NewV0Fitter.cc.

◆ fitAndStore()

bool fitAndStore	(	const Track *	trackPlus,
		const Track *	trackMinus,
		const Const::ParticleType &	v0Hypothesis,
		bool &	isForceStored,
		bool &	isHitRemoved
	)

Fit V0 with given hypothesis and store results if fit is successful.

Parameters

trackPlus	positively charged track
trackMinus	negatively charged track
v0Hypothesis	V0 hypothesis
isForceStored	true if V0 is forced to store when hit removal failed [out]
isHitRemoved	true if inner hits have been removed (or at least tried to be removed) [out]

Returns: true on success

Initialize status flags and result storage

Get related recoTracks

PDG codes actually used in track fitting

initial vertex fit

try to refit tracks by removing inner hits and refit the vertex

Usually this procedure converges in up to 3 iterations (mostly in a single iteration), but for a small fraction of track pairs it does not converge at all, so we set the limit at 5.

save the results

Definition at line 83 of file NewV0Fitter.cc.

◆ fitGFRaveVertex()

bool fitGFRaveVertex	(	genfit::Track &	trackPlus,
		genfit::Track &	trackMinus,
		genfit::GFRaveVertex &	vertex
	)

private

Genfit Rave vertex fit called by vertexFit method.

Parameters

trackPlus	positively charged genfit track
trackMinus	negatively charged genfit track
vertex	fitted vertex [out]

Returns: true on success

Definition at line 254 of file NewV0Fitter.cc.

◆ getTrackHypotheses()

std::pair< Const::ParticleType, Const::ParticleType > getTrackHypotheses ( const Const::ParticleType & v0Hypothesis )

static

Returns daughter particle types for a given V0 hypothesis.

Parameters

v0Hypothesis V0 hypothesis

Returns: a pair of daughter particle types

Definition at line 67 of file NewV0Fitter.cc.

◆ getTrackRepresentation()

const genfit::AbsTrackRep * getTrackRepresentation	(	const RecoTrack *	recoTrack,
		int	pdgCode
	)

private

Returns track representation for a given PDG code.

Parameters

recoTrack	track
pdgCode	PDG code

Returns: track representation on success or nullptr on failure

Definition at line 229 of file NewV0Fitter.cc.

◆ initializeCuts()

void initializeCuts	(	double	vertexDistanceCut,
		double	vertexChi2Cut,
		const std::tuple< double, double > &	invMassRangeKshort,
		const std::tuple< double, double > &	invMassRangeLambda,
		const std::tuple< double, double > &	invMassRangePhoton
	)

Initialization of cuts applied during the fit and store process.

Parameters

vertexDistanceCut	cut on the transverse radius to cut-off vertices within the beam pipe
vertexChi2Cut	cut on the vertex chi^2
invMassRangeKshort	selection mass window for Ks
invMassRangeLambda	selection mass window for Lambda
invMassRangePhoton	selection mass window for converted gamma

Definition at line 53 of file NewV0Fitter.cc.

◆ isInnermostClusterShared()

int isInnermostClusterShared	(	const RecoTrack *	recoTrackPlus,
		const RecoTrack *	recoTrackMinus
	)

private

Returns bit flags indicating that the innermost cluster is shared between both tracks.

Bit 0 is set if U cluster is shared, bit 1 is set if V cluster is shared, and both if shared cluster is PXD.

Parameters

recoTrackPlus	positively charged track
recoTrackMinus	negatively charged track

Returns: bit flags

Definition at line 409 of file NewV0Fitter.cc.

◆ removeHitsAndRefit()

const RecoTrack * removeHitsAndRefit	(	const RecoTrack *	origRecoTrack,
		const RecoTrack *	lastRecoTrack,
		const Const::ParticleType &	ptype
	)

private

Remove track inner hits and refit the track.

On success return the refitted one, otherwise return the track of last iteration (or the original one if no hits need to be removed).

Parameters

origRecoTrack	original track
lastRecoTrack	track at last hit-removal iteration
ptype	particle type for refit

Returns: refitted track on success, lastRecoTrack on failure, origRecoTrack if no hits removed

This shouldn't ever happen, but I can see the extrapolation code trying several windings before giving up, so this happens occasionally. Something more stable would perhaps be desirable.

Definition at line 308 of file NewV0Fitter.cc.

◆ saveTrackFitResult()

const TrackFitResult * saveTrackFitResult	(	const FittedTrack &	trk,
		int	sharedInnermostCluster
	)

private

Append track fit result to the collection.

Parameters

trk	track data
sharedInnermostCluster	bit flags of shared innermost clusters

Returns: track fit result

Definition at line 463 of file NewV0Fitter.cc.

◆ setCardinalRep()

bool setCardinalRep	(	genfit::Track &	gfTrack,
		int	pdgCode
	)

private

Sets cardinal representation of a given genfit track and PDG code.

Parameters

gfTrack	genfit track [in/out]
pdgCode	PDG code

Returns: true on success

Definition at line 239 of file NewV0Fitter.cc.

◆ setFitterMode()

void setFitterMode ( int fitterMode )

inline

Setter for the fitter mode.

0: store V0 at the first vertex fit, regardless of inner hits 1: remove hits inside the V0 vertex position (default) 2: mode 1 + don't use SVD hits if there is only one available SVD hit-pair

Parameters

fitterMode fitter mode

Definition at line 101 of file NewV0Fitter.h.

◆ vertexFit()

int vertexFit	(	const RecoTrack *	recoTrackPlus,
		const RecoTrack *	recoTrackMinus,
		int	pdgTrackPlus,
		int	pdgTrackMinus,
		const Const::ParticleType &	v0Hypothesis
	)

private

Performs a vertex fit.

On success the return value indicates if tracks have inner hits or not (see EInnerHitBits). On failure it returns ErrorStatus code.

Parameters

recoTrackPlus	positively charged track
recoTrackMinus	negatively charged track
pdgTrackPlus	PDG code used in the fit of positively charged track (closest mass to V0 daughter)
pdgTrackMinus	PDG code used in the fit of negatively charged track (closest mass to V0 daughter)
v0Hypothesis	V0 hypothesis

Returns: value >= 0 on success, value < 0 on failure

Definition at line 165 of file NewV0Fitter.cc.

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

tracking/v0Finding/fitter/include/NewV0Fitter.h
tracking/v0Finding/fitter/src/NewV0Fitter.cc

Classes

Public Member Functions

Static Public Member Functions

Private Types

Private Member Functions

Private Attributes

Detailed Description

Member Enumeration Documentation

◆ EInnerHitBits

◆ ErrorStatus

Constructor & Destructor Documentation

◆ NewV0Fitter()

Member Function Documentation

◆ copyRecoTrack()

◆ extrapolateToVertex()

◆ fitAndStore()

◆ fitGFRaveVertex()

◆ getTrackHypotheses()

◆ getTrackRepresentation()

◆ initializeCuts()

◆ isInnermostClusterShared()

◆ removeHitsAndRefit()

◆ saveTrackFitResult()

◆ setCardinalRep()

◆ setFitterMode()

◆ vertexFit()