The class 'FourHitFilters' bundles filter methods using 4 hits which are stored in B2Vector3Ds. More...

#include <FourHitFilters.h>

Public Member Functions
	FourHitFilters ()
	Empty constructor.

	FourHitFilters (const B2Vector3D &outer, const B2Vector3D &outerCenter, const B2Vector3D &innerCenter, const B2Vector3D &inner, const double magneticFieldStrength=1.5)
	Constructor.

	~FourHitFilters ()
	Destructor.

void	resetValues (const B2Vector3D &outer, const B2Vector3D &outerCenter, const B2Vector3D &innerCenter, const B2Vector3D &inner)
	Overrides Constructor-Setup.

void	resetMagneticField (const double magneticFieldStrength=1.5)
	Overrides Constructor-Setup for magnetic field.

double	calcDeltapT ()
	calculates dpt-value (dpt= difference in transverse momentum of 2 subsets of the hits), returning unit: GeV/c

double	deltapT ()
	legacy - compatibility for old cases

double	calcDeltaDistCircleCenter ()
	calculates ddist2IP-value directly (ddist2IP= difference in magnitude of the points of closest approach of two circles calculated using 2 subsets of the hits)

double	deltaDistCircleCenter ()
	legacy - compatibility for old cases

Protected Member Functions
void	calcCircle ()
	calculates an estimation of circleCenter position including an estimation for the circle radius

Protected Attributes
B2Vector3D	m_hitA
	outer hit (position relevant for useful filter calculation) used for the filter calculation

B2Vector3D	m_hitB
	outerCenter hit (position relevant for useful filter calculation) used for the filter calculation

B2Vector3D	m_hitC
	innerCenter hit (position relevant for useful filter calculation) used for the filter calculation

B2Vector3D	m_hitD
	inner hit (position relevant for useful filter calculation) used for the filter calculation

B2Vector3D	m_centerABC
	estimation of a circleCenterPosition using hits A, B & C

B2Vector3D	m_centerBCD
	estimation of a circleCenterPosition using hitsBA, C & D

double	m_radiusABC
	estimation of the radius of the circle using hits A, B & C

double	m_radiusBCD
	estimation of a radius of the circle using hitsBA, C & D

ThreeHitFilters	m_threeHitFilter
	instance of ThreeHitFilters-class used for some internal calculations

bool	m_circleCalculated
	initially set to false, will be set true if calcCircle() is used at least once

Detailed Description

The class 'FourHitFilters' bundles filter methods using 4 hits which are stored in B2Vector3Ds.

Definition at line 23 of file FourHitFilters.h.

Constructor & Destructor Documentation

◆ FourHitFilters() [1/2]

FourHitFilters ( )

inline

Empty constructor.

For initialisation only, an object generated this way is useless unless resetValues(a, b) is called at least once

Definition at line 28 of file FourHitFilters.h.

                    :
      m_radiusABC(0.),
      m_radiusBCD(0.),
      m_circleCalculated(false) {}

◆ FourHitFilters() [2/2]

FourHitFilters	(	const B2Vector3D &	outer,
		const B2Vector3D &	outerCenter,
		const B2Vector3D &	innerCenter,
		const B2Vector3D &	inner,
		const double	magneticFieldStrength = `1.5`
	)

inline

Constructor.

expects 4 hits in B2Vector3D format, first parameter is outer hit, second is outerCenter hit, third is innercenter hit, last one is the innermost hit, optional parameter sets strength of magnetic field (standard is 1.5T)

Definition at line 34 of file FourHitFilters.h.

                                                            :
      m_hitA(outer),
      m_hitB(outerCenter),
      m_hitC(innerCenter),
      m_hitD(inner),
      m_radiusABC(0.),
      m_radiusBCD(0.),
      m_circleCalculated(false) { m_threeHitFilter.resetMagneticField(magneticFieldStrength); }

◆ ~FourHitFilters()

~FourHitFilters ( )

inline

Destructor.

Definition at line 46 of file FourHitFilters.h.

46{}

Member Function Documentation

◆ calcCircle()

void calcCircle ( )

inlineprotected

calculates an estimation of circleCenter position including an estimation for the circle radius

Definition at line 81 of file FourHitFilters.h.

    {
      m_threeHitFilter.calcCircleCenter(m_hitA, m_hitB, m_hitC, m_centerABC);
      m_radiusABC = m_threeHitFilter.calcRadius(m_hitA, m_hitB, m_hitC, m_centerABC);
      m_threeHitFilter.calcCircleCenter(m_hitB, m_hitC, m_hitD, m_centerBCD);
      m_radiusBCD = m_threeHitFilter.calcRadius(m_hitB, m_hitC, m_hitD, m_centerBCD);
 
      m_circleCalculated = true;
    }

◆ calcDeltaDistCircleCenter()

double calcDeltaDistCircleCenter ( )

calculates ddist2IP-value directly (ddist2IP= difference in magnitude of the points of closest approach of two circles calculated using 2 subsets of the hits)

Definition at line 26 of file FourHitFilters.cc.

{
  if (m_circleCalculated == false) { calcCircle(); }
  return (fabs(m_centerABC.Perp() - m_centerBCD.Perp())); // distance between both guesses of the intersection point
} // return unit: cm

◆ calcDeltapT()

double calcDeltapT ( )

calculates dpt-value (dpt= difference in transverse momentum of 2 subsets of the hits), returning unit: GeV/c

TODO: evtly do a 'nan'-check for return values.

Definition at line 17 of file FourHitFilters.cc.

{
  if (m_circleCalculated == false) { calcCircle(); }
  return fabs(m_threeHitFilter.calcPt(m_radiusABC -
                                      m_radiusBCD)); // , or, pT[GeV/c] = 0.299710*B[T]*r[m] = 0,449565*r[cm]/100 = 0.00449565*r[cm]
}

◆ deltaDistCircleCenter()

double deltaDistCircleCenter ( )

inline

legacy - compatibility for old cases

Definition at line 77 of file FourHitFilters.h.

77{ return calcDeltaDistCircleCenter(); }

Belle2::FourHitFilters::calcDeltaDistCircleCenter

double calcDeltaDistCircleCenter()

calculates ddist2IP-value directly (ddist2IP= difference in magnitude of the points of closest approa...

Definition: FourHitFilters.cc:26

◆ deltapT()

double deltapT ( )

inline

legacy - compatibility for old cases

Definition at line 69 of file FourHitFilters.h.

69{ return calcDeltapT(); }

Belle2::FourHitFilters::calcDeltapT

double calcDeltapT()

calculates dpt-value (dpt= difference in transverse momentum of 2 subsets of the hits),...

Definition: FourHitFilters.cc:17

◆ resetMagneticField()

void resetMagneticField ( const double magneticFieldStrength = 1.5 )

inline

Overrides Constructor-Setup for magnetic field.

if no value is given, magnetic field is assumed to be Belle2-Detector standard of 1.5T

Definition at line 61 of file FourHitFilters.h.

61{ m_threeHitFilter.resetMagneticField(magneticFieldStrength); }

◆ resetValues()

void resetValues	(	const B2Vector3D &	outer,
		const B2Vector3D &	outerCenter,
		const B2Vector3D &	innerCenter,
		const B2Vector3D &	inner
	)

inline

Overrides Constructor-Setup.

Needed if you want to reuse the instance instead of recreating one

Definition at line 49 of file FourHitFilters.h.

    {
      m_hitA = outer;
      m_hitB = outerCenter;
      m_hitC = innerCenter;
      m_hitD = inner;
      m_radiusABC = 0.;
      m_radiusBCD = 0.;
      m_circleCalculated = false;
    }

Member Data Documentation

◆ m_centerABC

B2Vector3D m_centerABC

protected

estimation of a circleCenterPosition using hits A, B & C

Definition at line 95 of file FourHitFilters.h.

◆ m_centerBCD

B2Vector3D m_centerBCD

protected

estimation of a circleCenterPosition using hitsBA, C & D

Definition at line 96 of file FourHitFilters.h.

◆ m_circleCalculated

bool m_circleCalculated

protected

initially set to false, will be set true if calcCircle() is used at least once

Definition at line 100 of file FourHitFilters.h.

◆ m_hitA

B2Vector3D m_hitA

protected

outer hit (position relevant for useful filter calculation) used for the filter calculation

Definition at line 91 of file FourHitFilters.h.

◆ m_hitB

B2Vector3D m_hitB

protected

outerCenter hit (position relevant for useful filter calculation) used for the filter calculation

Definition at line 92 of file FourHitFilters.h.

◆ m_hitC

B2Vector3D m_hitC

protected

innerCenter hit (position relevant for useful filter calculation) used for the filter calculation

Definition at line 93 of file FourHitFilters.h.

◆ m_hitD

B2Vector3D m_hitD

protected

inner hit (position relevant for useful filter calculation) used for the filter calculation

Definition at line 94 of file FourHitFilters.h.

◆ m_radiusABC

double m_radiusABC

protected

estimation of the radius of the circle using hits A, B & C

Definition at line 97 of file FourHitFilters.h.

◆ m_radiusBCD

double m_radiusBCD

protected

estimation of a radius of the circle using hitsBA, C & D

Definition at line 98 of file FourHitFilters.h.

◆ m_threeHitFilter

ThreeHitFilters m_threeHitFilter

protected

instance of ThreeHitFilters-class used for some internal calculations

Definition at line 99 of file FourHitFilters.h.

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

tracking/vxdCaTracking/include/FourHitFilters.h
tracking/vxdCaTracking/src/FourHitFilters.cc

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ FourHitFilters() [1/2]

◆ FourHitFilters() [2/2]

◆ ~FourHitFilters()

Member Function Documentation

◆ calcCircle()

◆ calcDeltaDistCircleCenter()

◆ calcDeltapT()

◆ deltaDistCircleCenter()

◆ deltapT()

◆ resetMagneticField()

◆ resetValues()

Member Data Documentation

◆ m_centerABC

◆ m_centerBCD

◆ m_circleCalculated

◆ m_hitA

◆ m_hitB

◆ m_hitC

◆ m_hitD

◆ m_radiusABC

◆ m_radiusBCD

◆ m_threeHitFilter