Algorithm for hit finding in sensors with orthogonal strips. More...

#include <CbmStsAlgoFindHitsOrtho.h>

Public Member Functions
	CbmStsAlgoFindHitsOrtho ()
	Constructor.

	CbmStsAlgoFindHitsOrtho (const CbmStsAlgoFindHitsOrtho &)=delete
	Copy constructor (disabled)

CbmStsAlgoFindHitsOrtho &	operator= (const CbmStsAlgoFindHitsOrtho &)=delete
	Assignment operator (disabled)

virtual	~CbmStsAlgoFindHitsOrtho ()
	Destructor

Long64_t	Exec (const std::vector< CbmStsCluster > &clustersF, const std::vector< CbmStsCluster > &clustersB, std::vector< CbmStsHit > &hits, UInt_t address, Double_t timeCutSig, Double_t timeCutAbs, UInt_t nStripsF, UInt_t nStripsB, Double_t pitchF, Double_t pitchB, Double_t lorentzF, Double_t lorentzB, TGeoHMatrix *matrix)
	Execute algorithm.

Private Member Functions
void	CreateHit (Double_t xLocal, Double_t yLocal, Double_t varX, Double_t varY, Double_t varXY, const CbmStsCluster &clusterF, const CbmStsCluster &clusterB, UInt_t indexF, UInt_t indexB, Double_t du=0., Double_t dv=0.)
	Create a new hit in the output array.

void	GetClusterPosition (Double_t ClusterCentre, Double_t &xCluster, Int_t &side)

Int_t	GetSide (Double_t channel) const

std::pair< Int_t, Int_t >	GetStrip (UInt_t channel) const
	Get strip and side from module channel.

Int_t	IntersectClusters (const CbmStsCluster &clusterF, const CbmStsCluster &clusterB, UInt_t indexF, UInt_t indexB)
	Find the intersection points of two clusters.

Bool_t	IsInside (Double_t x, Double_t y)
	Check whether a point (x,y) is inside the active area.

	ClassDef (CbmStsAlgoFindHitsOrtho, 1)

Private Attributes
UInt_t	fAddress = 0
	Unique address for hits (sensor)

Double_t	fTimeCutSig = 0.
	Time cut on clusters in error units.

Double_t	fTimeCutAbs = 0.
	Time cut on clusters in ns.

UInt_t	fNofStripsF = 0
	Number of strips front side.

UInt_t	fNofStripsB = 0
	Number of strips backs side.

Double_t	fDx = 0.
	Active size in x [cm].

Double_t	fDy = 0.
	Active size in y [cm].

Double_t	fPitchF = 0.
	Strip pitch front side [cm].

Double_t	fPitchB = 0.
	Strip pitch back side [cm].

Double_t	fLorentzF = 0.
	Lorentz shift correction front side [cm].

Double_t	fLorentzB = 0.
	Lorentz shift correction back side [cm].

TGeoHMatrix *	fMatrix = nullptr

std::vector< CbmStsHit > *	fHits = nullptr
	///< Transformation matrix to global C.S.

Detailed Description

Algorithm for hit finding in sensors with orthogonal strips.

Author: V.Friese v.fri.nosp@m.ese@.nosp@m.gsi.d.nosp@m.e; F. Boeck (FIAS)

Since: 23.03.2020

A hit is constructed from two clusters, one from the front side, the other one from the back side of the sensor, if they two clusters have a geometrical intersection in the active sensor area, and if they are compatible in time. The algorithm combines front-side with back-side clusters and checks for these conditions. The hit coordinates are transformed into the global coordinate system.

The loop over the clusters was optimised by F. Boeck for application to free-streaming data (not sorted into events).

Definition at line 40 of file CbmStsAlgoFindHitsOrtho.h.

Constructor & Destructor Documentation

◆ CbmStsAlgoFindHitsOrtho() [1/2]

CbmStsAlgoFindHitsOrtho::CbmStsAlgoFindHitsOrtho ( )

Constructor.

Definition at line 28 of file CbmStsAlgoFindHitsOrtho.cxx.

◆ CbmStsAlgoFindHitsOrtho() [2/2]

CbmStsAlgoFindHitsOrtho::CbmStsAlgoFindHitsOrtho ( const CbmStsAlgoFindHitsOrtho & )

delete

Copy constructor (disabled)

◆ ~CbmStsAlgoFindHitsOrtho()

virtual CbmStsAlgoFindHitsOrtho::~CbmStsAlgoFindHitsOrtho ( )

inlinevirtual

Destructor

Definition at line 56 of file CbmStsAlgoFindHitsOrtho.h.

Member Function Documentation

◆ ClassDef()

CbmStsAlgoFindHitsOrtho::ClassDef	(	CbmStsAlgoFindHitsOrtho	,
		1	)

private

◆ CreateHit()

void CbmStsAlgoFindHitsOrtho::CreateHit	(	Double_t	xLocal,
		Double_t	yLocal,
		Double_t	varX,
		Double_t	varY,
		Double_t	varXY,
		const CbmStsCluster &	clusterF,
		const CbmStsCluster &	clusterB,
		UInt_t	indexF,
		UInt_t	indexB,
		Double_t	du = 0.,
		Double_t	dv = 0. )

private

Create a new hit in the output array.

Parameters

xLocal	hit x coordinate in sensor system [cm]
yLocal	hit y coordinate in sensor system [cm]
varX	Variance in x [cm^2]
varY	Variance in y [cm^2]
varXY	Covariance of x and y [cm^2]
clusterF	Front-side cluster
clusterB	Back-side cluster
indexF	Index of front-side cluster
indexB	Index of back-side cluster
du	Error in u coordinate (across strips front side) [cm]
dv	Error in v coordinate (across strips back side) [cm]

Definition at line 33 of file CbmStsAlgoFindHitsOrtho.cxx.

References fAddress, fHits, fMatrix, CbmStsCluster::GetTime(), and CbmStsCluster::GetTimeError().

Referenced by IntersectClusters().

◆ Exec()

Long64_t CbmStsAlgoFindHitsOrtho::Exec	(	const std::vector< CbmStsCluster > &	clustersF,
		const std::vector< CbmStsCluster > &	clustersB,
		std::vector< CbmStsHit > &	hits,
		UInt_t	address,
		Double_t	timeCutSig,
		Double_t	timeCutAbs,
		UInt_t	nStripsF,
		UInt_t	nStripsB,
		Double_t	pitchF,
		Double_t	pitchB,
		Double_t	lorentzF,
		Double_t	lorentzB,
		TGeoHMatrix *	matrix )

Execute algorithm.

Parameters

clustersF	Input clusters front side
clusterB	Input clusters back side
hits	Output hits
Hit	address ( = module address)
timeCutSig	Time cut in units of cluster time error
timeCutAbs	Time cut in ns
dY	Vertical size of the active sensor area [cm]
nStripsF	Number of strips on front side
nStripsB	Number of strips on back side
pitchF	Strip pitch on front side [cm]
pitchB	Strip pitch on back side [cm]
lorentzF	Mean Lorentz shift front side (electrons) [cm]
lorentzB	Mean Lorentz shift back side (holes) [cm]
matrix	Transformation matrix from local to global C.S.

Returns: Number of created hits

Definition at line 73 of file CbmStsAlgoFindHitsOrtho.cxx.

References fAddress, fDx, fDy, fHits, fLorentzB, fLorentzF, fMatrix, fNofStripsB, fNofStripsF, fPitchB, fPitchF, CbmStsCluster::GetTime(), CbmStsCluster::GetTimeError(), hits, and IntersectClusters().

Referenced by CbmStsRecoModule::FindHits().

◆ GetClusterPosition()

void CbmStsAlgoFindHitsOrtho::GetClusterPosition	(	Double_t	ClusterCentre,
		Double_t &	xCluster,
		Int_t &	side )

private

Get the cluster position at the top edge of the sensor.

Parameters

[in]	centre	Cluster centre in (module) channel units
[out]	xCluster	Cluster position at readout edge
[out]	side	Sensor side [0 = front, 1 = back]

A correction for the Lorentz shift is applied.

Definition at line 163 of file CbmStsAlgoFindHitsOrtho.cxx.

References fLorentzB, fLorentzF, fPitchB, fPitchF, and GetStrip().

Referenced by IntersectClusters().

◆ GetSide()

Int_t CbmStsAlgoFindHitsOrtho::GetSide ( Double_t channel ) const

inlineprivate

Get the side of the sensor from the module channel number The channel number can also be the cluster position, so it needs not be integer.

Parameters

channel Channel number

Returns: Sensor side ( 0 = front, 1 = back)

Definition at line 117 of file CbmStsAlgoFindHitsOrtho.h.

References fNofStripsB, and fNofStripsF.

◆ GetStrip()

pair< Int_t, Int_t > CbmStsAlgoFindHitsOrtho::GetStrip ( UInt_t channel ) const

private

Get strip and side from module channel.

Parameters

[in]	channel	Channel number in module
[in]	sensorId	Sensor index in module @value Pair of strip number and side

Note: This must be the inverse of GetModuleChannel.

Definition at line 201 of file CbmStsAlgoFindHitsOrtho.cxx.

References fNofStripsF.

Referenced by GetClusterPosition().

◆ IntersectClusters()

Int_t CbmStsAlgoFindHitsOrtho::IntersectClusters	(	const CbmStsCluster &	clusterF,
		const CbmStsCluster &	clusterB,
		UInt_t	indexF,
		UInt_t	indexB )

private

Find the intersection points of two clusters.

Parameters

clusterF	Cluster on front side
clusterB	Cluster on back side
indexF	Index of cluster on front side
indexB	Index of cluster on back side

Returns: Number of intersection points inside active area

For each intersection point, a hit is created.

Definition at line 223 of file CbmStsAlgoFindHitsOrtho.cxx.

References CreateHit(), fDx, fDy, fPitchB, fPitchF, GetClusterPosition(), CbmStsCluster::GetPosition(), and CbmStsCluster::GetPositionError().

Referenced by Exec().

◆ IsInside()

Bool_t CbmStsAlgoFindHitsOrtho::IsInside	(	Double_t	x,
		Double_t	y )

private

Check whether a point (x,y) is inside the active area.

Parameters

x	x coordinate in the local c.s. [cm]
y	y coordinate in the local c.s. [cm]

Returns: kTRUE if inside active area.

The coordinates have to be given in the local coordinate system (origin in the sensor centre).

Definition at line 274 of file CbmStsAlgoFindHitsOrtho.cxx.

References fDx, fDy, x, and y.

◆ operator=()

CbmStsAlgoFindHitsOrtho & CbmStsAlgoFindHitsOrtho::operator= ( const CbmStsAlgoFindHitsOrtho & )

delete

Assignment operator (disabled)

Member Data Documentation

◆ fAddress

UInt_t CbmStsAlgoFindHitsOrtho::fAddress = 0

private

Unique address for hits (sensor)

Definition at line 159 of file CbmStsAlgoFindHitsOrtho.h.

Referenced by CreateHit(), and Exec().

◆ fDx

Double_t CbmStsAlgoFindHitsOrtho::fDx = 0.

private

Active size in x [cm].

Definition at line 164 of file CbmStsAlgoFindHitsOrtho.h.

Referenced by Exec(), IntersectClusters(), and IsInside().

◆ fDy

Double_t CbmStsAlgoFindHitsOrtho::fDy = 0.

private

Active size in y [cm].

Definition at line 165 of file CbmStsAlgoFindHitsOrtho.h.

Referenced by Exec(), IntersectClusters(), and IsInside().

◆ fHits

std::vector<CbmStsHit>* CbmStsAlgoFindHitsOrtho::fHits = nullptr

private

///< Transformation matrix to global C.S.

Output vector of hits

Definition at line 173 of file CbmStsAlgoFindHitsOrtho.h.

Referenced by CreateHit(), and Exec().

◆ fLorentzB

Double_t CbmStsAlgoFindHitsOrtho::fLorentzB = 0.

private

Lorentz shift correction back side [cm].

Definition at line 169 of file CbmStsAlgoFindHitsOrtho.h.

Referenced by Exec(), and GetClusterPosition().

◆ fLorentzF

Double_t CbmStsAlgoFindHitsOrtho::fLorentzF = 0.

private

Lorentz shift correction front side [cm].

Definition at line 168 of file CbmStsAlgoFindHitsOrtho.h.

Referenced by Exec(), and GetClusterPosition().

◆ fMatrix

TGeoHMatrix* CbmStsAlgoFindHitsOrtho::fMatrix = nullptr

private

Definition at line 170 of file CbmStsAlgoFindHitsOrtho.h.

Referenced by CreateHit(), and Exec().

◆ fNofStripsB

UInt_t CbmStsAlgoFindHitsOrtho::fNofStripsB = 0

private

Number of strips backs side.

Definition at line 163 of file CbmStsAlgoFindHitsOrtho.h.

Referenced by Exec(), and GetSide().

◆ fNofStripsF

UInt_t CbmStsAlgoFindHitsOrtho::fNofStripsF = 0

private

Number of strips front side.

Definition at line 162 of file CbmStsAlgoFindHitsOrtho.h.

Referenced by Exec(), GetSide(), and GetStrip().

◆ fPitchB

Double_t CbmStsAlgoFindHitsOrtho::fPitchB = 0.

private

Strip pitch back side [cm].

Definition at line 167 of file CbmStsAlgoFindHitsOrtho.h.

Referenced by Exec(), GetClusterPosition(), and IntersectClusters().

◆ fPitchF

Double_t CbmStsAlgoFindHitsOrtho::fPitchF = 0.

private

Strip pitch front side [cm].

Definition at line 166 of file CbmStsAlgoFindHitsOrtho.h.

Referenced by Exec(), GetClusterPosition(), and IntersectClusters().

◆ fTimeCutAbs

Double_t CbmStsAlgoFindHitsOrtho::fTimeCutAbs = 0.

private

Time cut on clusters in ns.

Definition at line 161 of file CbmStsAlgoFindHitsOrtho.h.

◆ fTimeCutSig

Double_t CbmStsAlgoFindHitsOrtho::fTimeCutSig = 0.

private

Time cut on clusters in error units.

Definition at line 160 of file CbmStsAlgoFindHitsOrtho.h.

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

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ CbmStsAlgoFindHitsOrtho() [1/2]

◆ CbmStsAlgoFindHitsOrtho() [2/2]

◆ ~CbmStsAlgoFindHitsOrtho()

Member Function Documentation

◆ ClassDef()

◆ CreateHit()

◆ Exec()

◆ GetClusterPosition()

◆ GetSide()

◆ GetStrip()

◆ IntersectClusters()

◆ IsInside()

◆ operator=()

Member Data Documentation

◆ fAddress

◆ fDx

◆ fDy

◆ fHits

◆ fLorentzB

◆ fLorentzF

◆ fMatrix

◆ fNofStripsB

◆ fNofStripsF

◆ fPitchB

◆ fPitchF

◆ fTimeCutAbs

◆ fTimeCutSig