representation of the photon constraint More...

#include <RecoPhoton.h>

Inheritance diagram for RecoPhoton:

Collaboration diagram for RecoPhoton:

[legend]

Public Types
enum	TFParticleType { kInteractionPoint, kOrigin, kRecoComposite, kRecoResonance, kInternalParticle, kRecoTrack, kResonance, kRecoPhoton, kRecoKlong, kMissingParticle, kFeedthroughParticle, kInternalTrack }
	particle types

typedef std::vector< Constraint >	constraintlist
	alias

typedef std::vector< std::pair< const ParticleBase *, int > >	indexmap
	alias

Public Member Functions
	RecoPhoton (Belle2::Particle bc, const ParticleBase mother)
	constructor

virtual	~RecoPhoton ()
	destructor

virtual ErrCode	initParticleWithMother (FitParams &fitparams) override
	init particle with mother

virtual ErrCode	initMotherlessParticle (FitParams &fitparams) override
	init particle without mother

ErrCode	initCovariance (FitParams &fitparams) const override
	init covariance

ErrCode	initParams ()
	update or init params

ErrCode	projectRecoConstraint (const FitParams &fitparams, Projection &p) const override
	project photon constraint More...

virtual int	dimM () const override
	sets the size of the corresponding residual projection

virtual bool	hasEnergy () const override
	how should the energy be calculated ? from momentum or from E ?

virtual int	dim () const override
	set the size of the particle in the statevector

virtual int	type () const override
	type

virtual void	addToConstraintList (constraintlist &alist, int depth) const override
	add to list

virtual std::string	parname (int index) const override
	name

virtual int	momIndex () const override
	get momentum index

virtual ErrCode	projectConstraint (Constraint::Type, const FitParams &, Projection &) const override
	abstract abstract projection

virtual void	updateIndex (int &offset)
	this sets the index for momentum, position, etc. More...

const ParticleBase *	locate (Belle2::Particle *particle) const
	get particle base from basf2 particle

Belle2::Particle *	particle () const
	get basf2 particle

int	index () const
	get index

const ParticleBase *	mother () const
	getMother() / hasMother()

const std::string &	name () const
	get name of the particle

virtual ErrCode	projectGeoConstraint (const FitParams &, Projection &) const
	project geometrical constraint More...

virtual ErrCode	projectMassConstraintParticle (const FitParams &, Projection &) const
	project mass constraint using the particles parameters More...

virtual ErrCode	projectMassConstraintDaughters (const FitParams &, Projection &) const
	project mass constraint using the parameters of the daughters More...

virtual ErrCode	projectMassConstraint (const FitParams &, Projection &) const
	project mass constraint abstract

virtual void	forceP4Sum (FitParams &) const
	force p4 sum conservation all allong the tree

virtual int	posIndex () const
	get vertex index (in statevector!)

virtual int	tauIndex () const
	get tau index

virtual bool	hasPosition () const
	get false

int	eneIndex () const
	get energy index

virtual double	chiSquare (const FitParams &) const
	get chi2

double	pdgMass () const
	get pdg mass

double	pdgWidth () const
	get pdg width

double	pdgLifeTime () const
	get pdg lifetime

double	pdgTime () const
	get Tau

int	charge () const
	get charge

virtual ParticleBase *	addDaughter (Belle2::Particle *, const ConstraintConfiguration &config, bool forceFitAll=false)
	add daughter

virtual void	removeDaughter (const ParticleBase *pb)
	remove daughter

virtual void	retrieveIndexMap (indexmap &anindexmap) const
	get index map

void	setMother (const ParticleBase *m)
	set mother

void	collectVertexDaughters (std::vector< ParticleBase * > &particles, int posindex)
	get vertex daughters

virtual int	nFinalChargedCandidates () const
	number of charged candidates

void	setParticle (Belle2::Particle *particle)
	set the relation to basf2 particle type

Static Public Member Functions
static bool	useEnergy (const Belle2::Particle &cand)
	has energy in fit params?

static ParticleBase *	createParticle (Belle2::Particle particle, const ParticleBase mother, const ConstraintConfiguration &config, bool forceFitAll=false)
	create the according treeFitter particle obj for a basf2 particle type

static ParticleBase *	createOrigin (Belle2::Particle *daughter, const ConstraintConfiguration &config, bool forceFitAll)
	create a custom origin particle or a beamspot

Protected Types
typedef std::vector< ParticleBase * >	ParticleContainer
	just an alias

Protected Member Functions
ErrCode	initTau (FitParams &par) const
	initialises tau as a length

void	setIndex (int i)
	set Index (in statevector)

Static Protected Member Functions
static double	pdgLifeTime (Belle2::Particle *particle)
	get pdg lifetime

static bool	isAResonance (Belle2::Particle *particle)
	controls if a particle is treated as a resonance(lifetime=0) or a particle that has a finite lifetime. More...

static double	bFieldOverC ()
	Bz/c

Protected Attributes
Belle2::Particle *	m_particle
	pointer to framework type

const ParticleBase *	m_mother
	motherparticle

std::vector< ParticleBase * >	m_daughters
	daughter container

bool	m_isStronglyDecayingResonance
	decay length less than 1 micron

const ConstraintConfiguration *	m_config
	has all the constraint config

Private Attributes
const int	m_dim
	dimension of residuals and 'width' of H

bool	m_init
	was initialized*

bool	m_useEnergy
	has energy ins statevector

Eigen::Matrix< double, 1, 4 >	m_clusterPars
	constrains measured params (x_c, y_c, z_c, E_c)

Eigen::Matrix< double, 4, 4 >	m_covariance
	covariance (x_c,y_c,z_c,E_c) of measured pars

int	m_i1
	index with the highest momentum. More...

int	m_i2
	random other index

int	m_i3
	another random index

int	m_index
	index

const double	m_pdgMass
	pdg mass

double	m_pdgWidth
	particle width

const double	m_pdgLifeTime
	lifetime in cm

int	m_charge
	charge

std::string	m_name
	name

Detailed Description

representation of the photon constraint

Definition at line 25 of file RecoPhoton.h.

Member Function Documentation

◆ isAResonance()

bool isAResonance ( Belle2::Particle * particle )

staticprotectedinherited

controls if a particle is treated as a resonance(lifetime=0) or a particle that has a finite lifetime.

A finite life time means it will register a geo constraint for this particle

Definition at line 235 of file ParticleBase.cc.

◆ projectGeoConstraint()

ErrCode projectGeoConstraint	(	const FitParams &	fitparams,
		Projection &	p
	)		const

virtualinherited

project geometrical constraint

the direction of the momentum is very well known from the kinematic constraints that is why we do not extract the distance as a vector here

Definition at line 359 of file ParticleBase.cc.

◆ projectMassConstraintDaughters()

ErrCode projectMassConstraintDaughters	(	const FitParams &	fitparams,
		Projection &	p
	)		const

virtualinherited

project mass constraint using the parameters of the daughters

be aware that the signs here are important E-|p|-m extracts a negative mass and messes with the momentum !

Definition at line 435 of file ParticleBase.cc.

◆ projectMassConstraintParticle()

ErrCode projectMassConstraintParticle	(	const FitParams &	fitparams,
		Projection &	p
	)		const

virtualinherited

project mass constraint using the particles parameters

be aware that the signs here are important E-|p|-m extracts a negative mass and messes with the momentum !

Definition at line 496 of file ParticleBase.cc.

◆ projectRecoConstraint()

ErrCode projectRecoConstraint	(	const FitParams &	fitparams,
		Projection &	p
	)		const

overridevirtual

project photon constraint

m : decay vertex mother p : momentum photon c : position cluster so: m + p = c thus (tau converts p to the correct units): 0 = c - m - tau * p we have 3 geometric equations and eliminate tau using the dimension with the highest momentum (because we have to divide by that momentum) only downside is we have to figure out which dimension this is the 4th equation is the energy which we keep as: 0 = E - |p| just to be sure, essentially this is always zero because p is build from E

Implements RecoParticle.

Definition at line 171 of file RecoPhoton.cc.

          :
      * m + p = c
      * thus (tau converts p to the correct units):
      * 0 = c - m - tau * p
      * we have 3 geometric equations and eliminate tau using the dimension with the highest momentum
      * (because we have to divide by that momentum)
      * only downside is we have to figure out which dimension this is
      * the 4th equation is the energy which we keep as:
      * 0 = E - |p|
      * just to be sure, essentially this is always zero because p is build from E
      * */
  
     const Eigen::Matrix<double, 1, 3> x_vertex = fitparams.getStateVector().segment(posindex, 3);
     const Eigen::Matrix<double, 1, 3> p_vec = fitparams.getStateVector().segment(momindex, 3);
  
     if (0 == p_vec[m_i1]) { return ErrCode(ErrCode::photondimerror); }
  
     // p_vec[m_i1] must not be 0
     const double elim = (m_clusterPars[m_i1] - x_vertex[m_i1]) / p_vec[m_i1];
     const double mom = p_vec.norm();
  
     // r'
     Eigen::Matrix<double, 3, 1> residual3 = Eigen::Matrix<double, 3, 1>::Zero(3, 1);
     residual3(0) = m_clusterPars[m_i2] - x_vertex[m_i2] - p_vec[m_i2] * elim;
     residual3(1) = m_clusterPars[m_i3] - x_vertex[m_i3] - p_vec[m_i3] * elim;
     residual3(2) = m_clusterPars[3] - mom;
  
     // dr'/dm | m:={xc,yc,zc,Ec} the measured quantities
     Eigen::Matrix<double, 3, 4> P = Eigen::Matrix<double, 3, 4>::Zero(3, 4);
     // deriving by the cluster pars
     P(0, m_i2) = 1;
     P(0, m_i1) = - p_vec[m_i2] / p_vec[m_i1];
  
     P(1, m_i3) = 1;
     P(1, m_i1) = - p_vec[m_i3] / p_vec[m_i1];
     P(2, 3) = 1; // dE/dEc
  
     p.getResiduals().segment(0, 3) = residual3;
  
     p.getV() = P * m_covariance.selfadjointView<Eigen::Lower>() * P.transpose();
  
     // dr'/dm  | m:={x,y,z,px,py,pz,E}
     // x := x_vertex (decay vertex of mother)
     p.getH()(0, posindex + m_i1) =  p_vec[m_i2] / p_vec[m_i1];
     p.getH()(0, posindex + m_i2) = -1.0;
     p.getH()(0, posindex + m_i3) = 0;
  
     p.getH()(1, posindex + m_i1) =  p_vec[m_i3] / p_vec[m_i1];
     p.getH()(1, posindex + m_i2) = 0;
     p.getH()(1, posindex + m_i3) = -1.0;
  
     // elim already devided by p_vec[m_i1]
     p.getH()(0, momindex + m_i1) = p_vec[m_i2] * elim / p_vec[m_i1];
     p.getH()(0, momindex + m_i2) = -1. * elim;
     p.getH()(0, momindex + m_i3) = 0;
  
     p.getH()(1, momindex + m_i1) = p_vec[m_i3] * elim / p_vec[m_i1];
     p.getH()(1, momindex + m_i2) = 0;
     p.getH()(1, momindex + m_i3) = -1. * elim;
  
     p.getH()(2, momindex + m_i1) = -1. * p_vec[m_i1] / mom;
     p.getH()(2, momindex + m_i2) = -1. * p_vec[m_i2] / mom;
     p.getH()(2, momindex + m_i3) = -1. * p_vec[m_i3] / mom;
     // the photon does not store an energy in the state vector
     // so no p.getH()(2, momindex + 3) here
  
     return ErrCode(ErrCode::Status::success);
   }
  
 }
  
  

◆ updateIndex()

void updateIndex ( int & offset )

virtualinherited

this sets the index for momentum, position, etc.

in the statevector

Definition at line 138 of file ParticleBase.cc.

Member Data Documentation

◆ m_i1

int m_i1

private

index with the highest momentum.

We have to make sure this does not change during the fit.

Definition at line 96 of file RecoPhoton.h.

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

analysis/VertexFitting/TreeFitter/include/RecoPhoton.h
analysis/VertexFitting/TreeFitter/src/RecoPhoton.cc

Public Types

Public Member Functions

Static Public Member Functions

Protected Types

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Private Attributes

Detailed Description

Member Function Documentation

◆ isAResonance()

◆ projectGeoConstraint()

◆ projectMassConstraintDaughters()

◆ projectMassConstraintParticle()

◆ projectRecoConstraint()

◆ updateIndex()

Member Data Documentation

◆ m_i1