base class for all particles More...

#include <ParticleBase.h>

Inheritance diagram for ParticleBase:

[legend]

Collaboration diagram for ParticleBase:

[legend]

Public Types
enum	TFParticleType { kInteractionPoint , kOrigin , kComposite , kRecoResonance , kInternalParticle , kRecoTrack , kResonance , kRecoPhoton , kRecoKlong , kMissingParticle }
	particle types More...

typedef std::vector< Constraint >	constraintlist
	alias

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

Public Member Functions
	ParticleBase (Belle2::Particle particle, const ParticleBase mother, const ConstraintConfiguration *config=nullptr)
	default constructor

	ParticleBase (const std::string &name)
	constructor only used by interaction point (ip constraint)

virtual	~ParticleBase ()
	destructor, actually does something

virtual ErrCode	initMotherlessParticle (FitParams &)=0
	init particle that does not need a mother vertex

virtual ErrCode	initParticleWithMother (FitParams &)=0
	init particle that does need a mother vertex

virtual ErrCode	initCovariance (FitParams &) const
	init covariance matrix

virtual int	dim () const =0
	get dimension of constraint

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

virtual std::string	parname (int index) const
	get name of parameter i

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()

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

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

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

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

virtual ErrCode	projectConstraint (Constraint::Type, const FitParams &, Projection &) const
	project constraint.

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

virtual int	type () const =0
	get particle type

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

virtual int	tauIndex () const
	get tau index

virtual int	momIndex () const
	get momentum index

virtual bool	hasEnergy () const
	get momentum dimension

virtual bool	hasPosition () const
	get false

int	eneIndex () const
	get energy index

virtual double	chiSquare (const FitParams &) const
	get chi2

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

virtual void	addToConstraintList (constraintlist &alist, int depth) const =0
	add to constraint list

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

virtual int	nFinalChargedCandidates () const
	number of charged candidates

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

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
int	m_index
	index

std::string	m_name
	name

Detailed Description

base class for all particles

Definition at line 25 of file ParticleBase.h.

Member Typedef Documentation

◆ constraintlist

typedef std::vector<Constraint> constraintlist

alias

Definition at line 52 of file ParticleBase.h.

◆ indexmap

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

alias

Definition at line 55 of file ParticleBase.h.

◆ ParticleContainer

typedef std::vector<ParticleBase*> ParticleContainer

protected

just an alias

Definition at line 178 of file ParticleBase.h.

Member Enumeration Documentation

◆ TFParticleType

enum TFParticleType

particle types

Definition at line 30 of file ParticleBase.h.

                        {kInteractionPoint,
                         kOrigin,
                         kComposite,
                         kRecoResonance,
                         kInternalParticle,
                         kRecoTrack,
                         kResonance,
                         kRecoPhoton,
                         kRecoKlong,
                         kMissingParticle
                        };

Constructor & Destructor Documentation

◆ ParticleBase() [1/2]

ParticleBase	(	Belle2::Particle *	particle,
		const ParticleBase *	mother,
		const ConstraintConfiguration *	config = `nullptr`
	)

default constructor

Definition at line 30 of file ParticleBase.cc.

                                                                                                                        :
    m_particle(particle),
    m_mother(mother),
    m_isStronglyDecayingResonance(false),
    m_config(config),
    m_index(0),
    m_name("Unknown")
  {
    if (particle) {
      m_isStronglyDecayingResonance = isAResonance(particle);
      const int pdgcode = particle->getPDGCode();
      if (pdgcode) { // PDG code != 0
        m_name = particle->getName();
      }
    }
  }

◆ ParticleBase() [2/2]

ParticleBase ( const std::string & name )

constructor only used by interaction point (ip constraint)

Definition at line 47 of file ParticleBase.cc.

                                                  :
    m_particle(nullptr),
    m_mother(nullptr),
    m_isStronglyDecayingResonance(false),
    m_config(nullptr),
    m_index(0),
    m_name(name)
  {}

◆ ~ParticleBase()

~ParticleBase ( )

virtual

destructor, actually does something

Definition at line 57 of file ParticleBase.cc.

  {
    for (auto daughter : m_daughters) {
      delete daughter;
    }
    m_daughters.clear();
  }

Member Function Documentation

◆ addDaughter()

ParticleBase * addDaughter	(	Belle2::Particle *	cand,
		const ConstraintConfiguration &	config,
		bool	forceFitAll = `false`
	)

virtual

add daughter

Definition at line 65 of file ParticleBase.cc.

  {
    auto newDaughter = ParticleBase::createParticle(cand, this, config, forceFitAll);
    m_daughters.push_back(newDaughter);
    return m_daughters.back();
  }

◆ addToConstraintList()

virtual void addToConstraintList	(	constraintlist &	alist,
		int	depth
	)		const

pure virtual

add to constraint list

Implemented in Composite, RecoKlong, RecoPhoton, RecoTrack, InternalParticle, Origin, and RecoResonance.

◆ charge()

int charge ( ) const

inline

get charge

Definition at line 144 of file ParticleBase.h.

    {
      if (m_particle->getPDGCode()) {
        double fltcharge = m_particle->getCharge();
        return fltcharge < 0 ? int(fltcharge - 0.5) : int(fltcharge + 0.5);
      } else {
        return m_particle->getCharge() > 0 ? 1 : (m_particle->getCharge() < 0 ? -1 : 0);
      }
    }

◆ chiSquare()

double chiSquare ( const FitParams & fitparams ) const

virtual

get chi2

Definition at line 231 of file ParticleBase.cc.

  {
    double rc = 0;
    for (auto* daughter : m_daughters) {
      rc += daughter->chiSquare(fitparams);
    }
    return rc;
  }

◆ collectVertexDaughters()

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

get vertex daughters

Definition at line 156 of file ParticleBase.cc.

  {
    if (mother() && mother()->posIndex() == posindex) {
      particles.push_back(this);
    }
 
    for (auto* daughter : m_daughters) {
      daughter->collectVertexDaughters(particles, posindex);
    }
  }

◆ createOrigin()

ParticleBase * createOrigin	(	Belle2::Particle *	daughter,
		const ConstraintConfiguration &	config,
		bool	forceFitAll
	)

static

create a custom origin particle or a beamspot

Definition at line 93 of file ParticleBase.cc.

  {
    return new Origin(daughter, config, forceFitAll);
  }

◆ createParticle()

ParticleBase * createParticle	(	Belle2::Particle *	particle,
		const ParticleBase *	mother,
		const ConstraintConfiguration &	config,
		bool	forceFitAll = `false`
	)

static

create the according treeFitter particle obj for a basf2 particle type

Definition at line 102 of file ParticleBase.cc.

  {
    ParticleBase* rc = nullptr;
 
    if (!mother) { // If there is no mother, this is the 'head of tree' particle (is never a resonance)
      rc = new InternalParticle(particle, nullptr, config, forceFitAll);
    } else if (particle->hasExtraInfo("bremsCorrected") // Has Bremsstrahlungs-recovery
               && particle->getExtraInfo("bremsCorrected") != 0) { // and gammas are attached
      rc = new Composite(particle, mother, config, true);
      // if no gamma is attached, it is treated as a RecoTrack
    } else if (particle->hasExtraInfo("treeFitterTreatMeAsInvisible")
               && particle->getExtraInfo("treeFitterTreatMeAsInvisible") == 1) { // dummy particles with invisible flag
      rc = new RecoResonance(particle, mother, config);
    } else if (particle->getTrack()) { // external reconstructed track
      rc = new RecoTrack(particle, mother);
    } else if (particle->getECLCluster()) { // external reconstructed photon
      rc = new RecoPhoton(particle, mother);
    } else if (particle->getKLMCluster()) { // external reconstructed klong
      rc = new RecoKlong(particle, mother);
    } else if (particle->getMdstArrayIndex()) { // external composite e.g. V0
      rc = new InternalParticle(particle, mother, config, forceFitAll);
    } else { // 'internal' particles
      if (isAResonance(particle)) {
        rc = new Resonance(particle, mother, config, forceFitAll);
      } else {
        rc = new InternalParticle(particle, mother, config, forceFitAll);
      }
    }
    return rc;
  }

◆ dim()

virtual int dim ( ) const

pure virtual

get dimension of constraint

Implemented in Composite, InternalParticle, Origin, RecoKlong, RecoParticle, RecoPhoton, RecoResonance, and Resonance.

◆ eneIndex()

int eneIndex ( ) const

inline

get energy index

Definition at line 138 of file ParticleBase.h.

138{ return hasEnergy() ? momIndex() + 3 : -1 ; }

TreeFitter::ParticleBase::momIndex

virtual int momIndex() const

get momentum index

Definition: ParticleBase.h:128

TreeFitter::ParticleBase::hasEnergy

virtual bool hasEnergy() const

get momentum dimension

Definition: ParticleBase.h:132

◆ forceP4Sum()

virtual void forceP4Sum ( FitParams & ) const

inlinevirtual

force p4 sum conservation all along the tree

Reimplemented in InternalParticle.

Definition at line 116 of file ParticleBase.h.

116{} ;

◆ hasEnergy()

virtual bool hasEnergy ( ) const

inlinevirtual

get momentum dimension

Reimplemented in Composite, InternalParticle, Origin, RecoKlong, RecoParticle, and RecoPhoton.

Definition at line 132 of file ParticleBase.h.

132{ return false ; }

◆ hasPosition()

virtual bool hasPosition ( ) const

inlinevirtual

get false

Reimplemented in Composite, InternalParticle, and Resonance.

Definition at line 135 of file ParticleBase.h.

135{ return false ; }

◆ index()

int index ( ) const

inline

get index

Definition at line 95 of file ParticleBase.h.

95{ return m_index ; }

◆ initCovariance()

ErrCode initCovariance ( FitParams & fitparams ) const

virtual

init covariance matrix

Reimplemented in InternalParticle, Origin, RecoKlong, RecoPhoton, and RecoTrack.

Definition at line 167 of file ParticleBase.cc.

  {
    // this is very sensitive and can heavily affect the efficiency of the fit
    ErrCode status;
 
    const int posindex = posIndex();
    if (posindex >= 0) {
      for (int i = 0; i < 3; ++i) {
        fitparams.getCovariance()(posindex + i, posindex + i) = 1;
      }
    }
 
    const int momindex = momIndex();
    if (momindex >= 0) {
      const int maxrow = hasEnergy() ? 4 : 3;
      for (int i = 0; i < maxrow; ++i) {
        fitparams.getCovariance()(momindex + i, momindex + i) = 10.;
      }
    }
 
    const int tauindex = tauIndex();
    if (tauindex >= 0) {
      fitparams.getCovariance()(tauindex, tauindex) = 1.;
    }
    return status;
  }

◆ initMotherlessParticle()

virtual ErrCode initMotherlessParticle ( FitParams & )

pure virtual

init particle that does not need a mother vertex

Implemented in Composite, InternalParticle, Origin, RecoKlong, RecoParticle, RecoPhoton, RecoResonance, RecoTrack, and Resonance.

◆ initParticleWithMother()

virtual ErrCode initParticleWithMother ( FitParams & )

pure virtual

init particle that does need a mother vertex

Implemented in Composite, InternalParticle, Origin, RecoKlong, RecoPhoton, RecoResonance, RecoTrack, and Resonance.

◆ initTau()

ErrCode initTau ( FitParams & par ) const

protected

initialises tau as a length

Definition at line 426 of file ParticleBase.cc.

  {
    const int tauindex = tauIndex();
    if (tauindex >= 0 && hasPosition()) {
 
      const int posindex = posIndex();
      const int mother_ps_index = mother()->posIndex();
      const int dim  = m_config->m_originDimension; // TODO can we configure this to be particle specific?
 
      // tau has different meaning depending on the dimension of the constraint
      // 2-> use x-y projection
      const Eigen::Matrix < double, 1, -1, 1, 1, 3 > vertex_dist =
        fitparams.getStateVector().segment(posindex, dim) - fitparams.getStateVector().segment(mother_ps_index, dim);
      const Eigen::Matrix < double, 1, -1, 1, 1, 3 >
      mom = fitparams.getStateVector().segment(posindex, dim) - fitparams.getStateVector().segment(mother_ps_index, dim);
 
      // if an intermediate vertex is not well defined by a track or so it will be initialised with 0
      // same for the momentum of for example B0, it might be initialised with 0
      // in those cases use pdg value
      const double mom_norm = mom.norm();
      const double dot = std::abs(vertex_dist.dot(mom));
      const double tau = dot / mom_norm;
      if (0 == mom_norm || 0 == dot) {
        const double mass = m_particle->getPDGMass();
        if (mass > 0)
          fitparams.getStateVector()(tauindex) = m_particle->getPDGLifetime() * 1e9 * Belle2::Const::speedOfLight / mass;
        else
          fitparams.getStateVector()(tauindex) = 0;
      } else {
        fitparams.getStateVector()(tauindex) = tau;
      }
    }
 
    return ErrCode(ErrCode::Status::success);
  }

◆ isAResonance()

bool isAResonance ( Belle2::Particle * particle )

staticprotected

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 134 of file ParticleBase.cc.

  {
    bool rc = false ;
    const int pdgcode = std::abs(particle->getPDGCode());
 
    if (pdgcode && !(particle->getMdstArrayIndex())) {
      switch (pdgcode) {
        case 22:  //photon conversion
          rc = false;
          break ;
 
        case -11: //bremsstrahlung
        case 11:
          rc = true ;
          break ;
        default: //everything with boosted flight length less than 1 micrometer
          rc = (pdgcode && particle->getPDGLifetime() < 1e-14);
      }
    }
    return rc ;
  }

◆ locate()

const ParticleBase * locate ( Belle2::Particle * particle ) const

get particle base from basf2 particle

Definition at line 211 of file ParticleBase.cc.

  {
    const ParticleBase* rc = (m_particle == particle) ? this : nullptr;
    if (!rc) {
      for (auto* daughter : m_daughters) {
        rc = daughter->locate(particle);
        if (rc) {break;}
      }
    }
    return rc;
  }

◆ momIndex()

virtual int momIndex ( ) const

inlinevirtual

get momentum index

Reimplemented in Composite, InternalParticle, Origin, RecoParticle, RecoResonance, and Resonance.

Definition at line 128 of file ParticleBase.h.

128{ return -1 ; }

◆ mother()

const ParticleBase * mother ( ) const

inline

getMother() / hasMother()

Definition at line 98 of file ParticleBase.h.

98{ return m_mother; };

◆ nFinalChargedCandidates()

int nFinalChargedCandidates ( ) const

virtual

number of charged candidates

Reimplemented in RecoTrack.

Definition at line 240 of file ParticleBase.cc.

  {
    int rc = 0;
    for (auto* daughter : m_daughters) {
      rc += daughter->nFinalChargedCandidates();
    }
    return rc;
  }

◆ parname()

std::string parname ( int index ) const

virtual

get name of parameter i

Reimplemented in InternalParticle, RecoParticle, RecoResonance, and Resonance.

Definition at line 194 of file ParticleBase.cc.

  {
    std::string rc = m_name;
    switch (thisindex) {
      case 0: rc += "_x  "; break;
      case 1: rc += "_y  "; break;
      case 2: rc += "_z  "; break;
      case 3: rc += "_tau"; break;
      case 4: rc += "_px "; break;
      case 5: rc += "_py "; break;
      case 6: rc += "_pz "; break;
      case 7: rc += "_E  "; break;
      default:;
    }
    return rc;
  }

◆ particle()

Belle2::Particle * particle ( ) const

inline

get basf2 particle

Definition at line 92 of file ParticleBase.h.

92{ return m_particle ; }

◆ posIndex()

virtual int posIndex ( ) const

inlinevirtual

get vertex index (in statevector!)

Reimplemented in Composite, InternalParticle, Origin, RecoResonance, and Resonance.

Definition at line 122 of file ParticleBase.h.

122{ return -1 ; }

◆ projectConstraint()

ErrCode projectConstraint	(	Constraint::Type	type,
		const FitParams &	fitparams,
		Projection &	p
	)		const

virtual

project constraint.

Reimplemented in InternalParticle, Composite, Origin, RecoParticle, and RecoResonance.

Definition at line 416 of file ParticleBase.cc.

  {
    if (type == Constraint::mass) {
      return projectMassConstraint(fitparams, p);
    } else {
      B2FATAL("Trying to project constraint of ParticleBase type. This is undefined.");
    }
    return ErrCode(ErrCode::Status::badsetup);
  }

◆ projectGeoConstraint()

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

virtual

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 249 of file ParticleBase.cc.

  {
    assert(m_config);
    // only allow 2d for head of tree particles that are beam constrained
    const int dim = m_config->m_originDimension == 2 && std::abs(m_particle->getPDGCode()) == m_config->m_headOfTreePDG ? 2 : 3;
    const int posindexmother = mother()->posIndex();
    const int posindex = posIndex();
    const int tauindex = tauIndex();
    const int momindex = momIndex();
 
    const double tau = fitparams.getStateVector()(tauindex);
    Eigen::Matrix < double, 1, -1, 1, 1, 3 > x_vec = fitparams.getStateVector().segment(posindex, dim);
    Eigen::Matrix < double, 1, -1, 1, 1, 3 > x_m = fitparams.getStateVector().segment(posindexmother, dim);
    Eigen::Matrix < double, 1, -1, 1, 1, 3 > p_vec = fitparams.getStateVector().segment(momindex, dim);
    const double mom = p_vec.norm();
    const double mom3 = mom * mom * mom;
 
    if (3 == dim) {
      // we can already set these
      //diagonal momentum
      p.getH()(0, momindex)     = tau * (p_vec(1) * p_vec(1) + p_vec(2) * p_vec(2)) / mom3 ;
      p.getH()(1, momindex + 1) = tau * (p_vec(0) * p_vec(0) + p_vec(2) * p_vec(2)) / mom3 ;
      p.getH()(2, momindex + 2) = tau * (p_vec(0) * p_vec(0) + p_vec(1) * p_vec(1)) / mom3 ;
 
      //offdiagonal momentum
      p.getH()(0, momindex + 1) = - tau * p_vec(0) * p_vec(1) / mom3 ;
      p.getH()(0, momindex + 2) = - tau * p_vec(0) * p_vec(2) / mom3 ;
 
      p.getH()(1, momindex + 0) = - tau * p_vec(1) * p_vec(0) / mom3 ;
      p.getH()(1, momindex + 2) = - tau * p_vec(1) * p_vec(2) / mom3 ;
 
      p.getH()(2, momindex + 0) = - tau * p_vec(2) * p_vec(0) / mom3 ;
      p.getH()(2, momindex + 1) = - tau * p_vec(2) * p_vec(1) / mom3 ;
 
    } else if (2 == dim) {
 
      // NOTE THAT THESE ARE DIFFERENT IN 2d
      p.getH()(0, momindex)     = tau * (p_vec(1) * p_vec(1)) / mom3 ;
      p.getH()(1, momindex + 1) = tau * (p_vec(0) * p_vec(0)) / mom3 ;
 
      //offdiagonal momentum
      p.getH()(0, momindex + 1) = - tau * p_vec(0) * p_vec(1) / mom3 ;
      p.getH()(1, momindex + 0) = - tau * p_vec(1) * p_vec(0) / mom3 ;
    } else {
      B2FATAL("Dimension of Geometric constraint is not 2 or 3. This will crash many things. You should feel bad.");
    }
 
    for (int row = 0; row < dim; ++row) {
 
      double posxmother = x_m(row);
      double posx       = x_vec(row);
      double momx       = p_vec(row);
 
      p.getResiduals()(row) = posxmother + tau * momx / mom - posx ;
      p.getH()(row, posindexmother + row) = 1;
      p.getH()(row, posindex + row) = -1;
      p.getH()(row, tauindex) = momx / mom;
    }
 
    return ErrCode(ErrCode::Status::success);
  }

◆ projectMassConstraint()

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

virtual

project mass constraint abstract

Definition at line 405 of file ParticleBase.cc.

  {
    assert(m_config);
    if (m_config->m_massConstraintType == 0) {
      return projectMassConstraintParticle(fitparams, p);
    } else {
      return projectMassConstraintDaughters(fitparams, p);
    }
  }

◆ projectMassConstraintDaughters()

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

virtual

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 314 of file ParticleBase.cc.

  {
    const double mass = particle()->getPDGMass();
    const double mass2 = mass * mass;
    double px = 0;
    double py = 0;
    double pz = 0;
    double E  = 0;
 
    // the parameters of the daughters must be used otherwise the mass constraint does not have an effect on the extracted daughter momenta
    for (const auto* daughter : m_daughters) {
      const int momindex = daughter->momIndex();
      // in most cases the daughters will be final states so we cache the value to use it in the energy column
      const double px_daughter = fitparams.getStateVector()(momindex);
      const double py_daughter = fitparams.getStateVector()(momindex + 1);
      const double pz_daughter = fitparams.getStateVector()(momindex + 2);
 
      px += px_daughter;
      py += py_daughter;
      pz += pz_daughter;
      if (daughter->hasEnergy()) {
        E += fitparams.getStateVector()(momindex + 3);
      } else {
        // final states dont have an energy index
        const double m = daughter->particle()->getPDGMass();
        E += std::sqrt(m * m + px_daughter * px_daughter + py_daughter * py_daughter + pz_daughter * pz_daughter);
      }
    }
 
    p.getResiduals()(0) = mass2 - E * E + px * px + py * py + pz * pz;
 
    for (const auto* daughter : m_daughters) {
      //dr/dx = d/dx m2-{E1+E2+...}^2+{p1+p2+...}^2 = 2*x (x= E or p)
      const int momindex = daughter->momIndex();
      p.getH()(0, momindex)     = 2.0 * px;
      p.getH()(0, momindex + 1) = 2.0 * py;
      p.getH()(0, momindex + 2) = 2.0 * pz;
 
      if (daughter->hasEnergy()) {
        p.getH()(0, momindex + 3) = -2.0 * E;
      } else {
        const double px_daughter = fitparams.getStateVector()(momindex);
        const double py_daughter = fitparams.getStateVector()(momindex + 1);
        const double pz_daughter = fitparams.getStateVector()(momindex + 2);
        const double m = daughter->particle()->getPDGMass();
 
        const double E_daughter = std::sqrt(m * m + px_daughter * px_daughter + py_daughter * py_daughter + pz_daughter * pz_daughter);
        const double E_by_E_daughter = E / E_daughter;
        p.getH()(0, momindex)     -= 2.0 * E_by_E_daughter * px_daughter;
        p.getH()(0, momindex + 1) -= 2.0 * E_by_E_daughter * py_daughter;
        p.getH()(0, momindex + 2) -= 2.0 * E_by_E_daughter * pz_daughter;
      }
 
    }
    return ErrCode(ErrCode::Status::success);
  }

◆ projectMassConstraintParticle()

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

virtual

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 375 of file ParticleBase.cc.

  {
    const double mass = particle()->getPDGMass();
    const double mass2 = mass * mass;
    const int momindex = momIndex();
    const double px = fitparams.getStateVector()(momindex);
    const double py = fitparams.getStateVector()(momindex + 1);
    const double pz = fitparams.getStateVector()(momindex + 2);
    const double E  = fitparams.getStateVector()(momindex + 3);
 
    p.getResiduals()(0) = mass2 - E * E + px * px + py * py + pz * pz;
 
    p.getH()(0, momindex)     = 2.0 * px;
    p.getH()(0, momindex + 1) = 2.0 * py;
    p.getH()(0, momindex + 2) = 2.0 * pz;
    p.getH()(0, momindex + 3) = -2.0 * E;
 
    // TODO 0 in most cases -> needs special treatment if width=0 to not crash chi2 calculation
    // const double width = TDatabasePDG::Instance()->GetParticle(particle()->getPDGCode())->Width();
    // transport  measurement uncertainty into residual system
    // f' = sigma_x^2 * (df/dx)^2
    // p.getV()(0) = width * width * 4 * mass2;
 
    return ErrCode(ErrCode::Status::success);
  }

◆ removeDaughter()

void removeDaughter ( const ParticleBase * pb )

virtual

remove daughter

Definition at line 73 of file ParticleBase.cc.

  {
    auto iter = std::find(m_daughters.begin(), m_daughters.end(), pb);
    if (iter != m_daughters.end()) {
      delete *iter;
      m_daughters.erase(iter);
    } else {
      B2ERROR("Cannot remove particle, because not found ...");
    }
  }

◆ retrieveIndexMap()

void retrieveIndexMap ( indexmap & anindexmap ) const

virtual

get index map

Definition at line 223 of file ParticleBase.cc.

  {
    map.push_back(std::pair<const ParticleBase*, int>(this, index()));
    for (auto* daughter : m_daughters) {
      daughter->retrieveIndexMap(map);
    }
  }

◆ setIndex()

void setIndex ( int i )

inlineprotected

set Index (in statevector)

Definition at line 189 of file ParticleBase.h.

189{ m_index = i ; }

◆ setMother()

void setMother ( const ParticleBase * m )

inline

set mother

Definition at line 164 of file ParticleBase.h.

164{ m_mother = m ; }

◆ tauIndex()

virtual int tauIndex ( ) const

inlinevirtual

get tau index

Reimplemented in Composite, InternalParticle, Origin, RecoResonance, and Resonance.

Definition at line 125 of file ParticleBase.h.

125{ return -1 ; }

◆ type()

virtual int type ( ) const

pure virtual

get particle type

Implemented in Composite, InternalParticle, Origin, RecoKlong, RecoPhoton, RecoResonance, RecoTrack, and Resonance.

◆ updateIndex()

void updateIndex ( int & offset )

virtual

this sets the index for momentum, position, etc.

in the statevector

Definition at line 84 of file ParticleBase.cc.

  {
    for (auto* daughter : m_daughters) {
      daughter->updateIndex(offset);
    }
    m_index = offset;
    offset += dim();
  }

Member Data Documentation

◆ m_config

const ConstraintConfiguration* m_config

protected

has all the constraint config

Definition at line 204 of file ParticleBase.h.

◆ m_daughters

std::vector<ParticleBase*> m_daughters

protected

daughter container

Definition at line 198 of file ParticleBase.h.

◆ m_index

int m_index

private

index

Definition at line 208 of file ParticleBase.h.

◆ m_isStronglyDecayingResonance

bool m_isStronglyDecayingResonance

protected

decay length less than 1 micron

Definition at line 201 of file ParticleBase.h.

◆ m_mother

const ParticleBase* m_mother

protected

motherparticle

Definition at line 195 of file ParticleBase.h.

◆ m_name

std::string m_name

private

name

Definition at line 211 of file ParticleBase.h.

◆ m_particle

Belle2::Particle* m_particle

protected

pointer to framework type

Definition at line 192 of file ParticleBase.h.

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

analysis/VertexFitting/TreeFitter/include/ParticleBase.h
analysis/VertexFitting/TreeFitter/src/ParticleBase.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 Typedef Documentation

◆ constraintlist

◆ indexmap

◆ ParticleContainer

Member Enumeration Documentation

◆ TFParticleType

Constructor & Destructor Documentation

◆ ParticleBase() [1/2]

◆ ParticleBase() [2/2]

◆ ~ParticleBase()

Member Function Documentation

◆ addDaughter()

◆ addToConstraintList()

◆ charge()

◆ chiSquare()

◆ collectVertexDaughters()

◆ createOrigin()

◆ createParticle()

◆ dim()

◆ eneIndex()

◆ forceP4Sum()

◆ hasEnergy()

◆ hasPosition()

◆ index()

◆ initCovariance()

◆ initMotherlessParticle()

◆ initParticleWithMother()

◆ initTau()

◆ isAResonance()

◆ locate()

◆ momIndex()

◆ mother()

◆ nFinalChargedCandidates()

◆ parname()

◆ particle()

◆ posIndex()

◆ projectConstraint()

◆ projectGeoConstraint()

◆ projectMassConstraint()

◆ projectMassConstraintDaughters()

◆ projectMassConstraintParticle()

◆ removeDaughter()

◆ retrieveIndexMap()

◆ setIndex()

◆ setMother()

◆ tauIndex()

◆ type()

◆ updateIndex()

Member Data Documentation

◆ m_config

◆ m_daughters

◆ m_index

◆ m_isStronglyDecayingResonance

◆ m_mother

◆ m_name

◆ m_particle