xAOD::NeutralParticle_v1 Class Reference

Class describing a NeutralParticle. More...

#include <NeutralParticle_v1.h>

Inheritance diagram for xAOD::NeutralParticle_v1:

Collaboration diagram for xAOD::NeutralParticle_v1:

Public Member Functions
	NeutralParticle_v1 ()
	Default constructor.
	~NeutralParticle_v1 ()
	Destructor.
	NeutralParticle_v1 (const NeutralParticle_v1 &o)
	Copy ctor. This involves copying the entire Auxilary store, and is a slow operation which should be used sparingly.
NeutralParticle_v1 &	operator= (const NeutralParticle_v1 &tp)
	Assignment operator. This can involve creating and copying an Auxilary store, and so should be used sparingly.

xAOD::IParticle functions
The transverse momentum ( \(p_T\)) of the particle.
typedef IParticle::FourMom_t	FourMom_t
	Definition of the 4-momentum type.
typedef ROOT::Math::LorentzVector< ROOT::Math::PxPyPzM4D< double > >	GenVecFourMom_t
	Base 4 Momentum type for TrackParticle.
virtual double	pt () const
	The transverse momentum ( \(p_T\)) of the particle.
virtual double	eta () const
	The pseudorapidity ( \(\eta\)) of the particle.
virtual double	phi () const
	The azimuthal angle ( \(\phi\)) of the particle.
virtual double	m () const
	The invariant mass of the particle..
virtual double	e () const
	The total energy of the particle.
virtual double	rapidity () const
	The true rapidity (y) of the particle.
virtual FourMom_t	p4 () const
	The full 4-momentum of the particle.
GenVecFourMom_t	genvecP4 () const
	The full 4-momentum of the particle : GenVector form.
virtual Type::ObjectType	type () const
	The type of the object as a simple enumeration.

Defining parameters functions
The 'defining parameters' are key to the concept of a NeutralParticle, and give the values for the IParticle interface ( pt(), phi(), eta() etc.). They use the Trk::NeutralPerigee coordinate system, and are defined as: \(( d_0, z_0, \phi, \theta, q/p )\). The parameters are expressed with respect to an origin (returned by vx(), vy() and vy() ), currently intended to be the 'beamspot'. This origin is expected to be the same for all track particles in a collection (and this may be be enforced).
CxxUtils::CachedValue< Trk::NeutralPerigee >	m_perigeeParameters
	Cached NeutralPerigee, built from this object.
float	d0 () const
	Returns the \(d_0\) parameter.
float	z0 () const
	Returns the \(z_0\) parameter.
float	phi0 () const
	Returns the \(\phi\) parameter, which has range \(-\pi\) to \(+\pi\).
float	theta () const
	Returns the \(\theta\) parameter, which has range 0 to \(\pi\).
float	oneOverP () const
	Returns the \(q/p\) parameter.
const DefiningParameters_t	definingParameters () const
	Returns a SVector of the Perigee track parameters.
const ParametersCovMatrix_t	definingParametersCovMatrix () const
	Returns the 5x5 symmetric matrix containing the defining parameters covariance matrix.
const std::vector< float > &	definingParametersCovMatrixVec () const
	Returns the vector of the covariance values - 15 elements.
void	setDefiningParameters (float d0, float z0, float phi0, float theta, float qOverP)
	Set the defining parameters.
void	setDefiningParametersCovMatrix (const ParametersCovMatrix_t &cov)
	Set the defining parameters covariance matrix.
void	setDefiningParametersCovMatrixVec (const std::vector< float > &cov)
	Set the defining parameters covariance matrix using a length 15 vector.
float	vx () const
	The x origin for the parameters.
float	vy () const
	The y origin for the parameters.
float	vz () const
	The z origin for the parameters.
void	setParametersOrigin (float x, float y, float z)
	Set the origin for the parameters.
const Trk::NeutralPerigee &	perigeeParameters () const
	Returns the Trk::NeutralPerigee track parameters.
void	resetCache ()
	Reset the internal cache of the object.

Functions for getting and setting user properties
template<class T>
XAOD_AUXDATA_DEPRECATED T &	auxdata (const std::string &name, const std::string &clsname="")
	Fetch an aux data variable, as a non-const reference.
template<class T>
XAOD_AUXDATA_DEPRECATED const T &	auxdata (const std::string &name, const std::string &clsname="") const
	Fetch an aux data variable, as a const reference.
template<class T>
XAOD_AUXDATA_DEPRECATED bool	isAvailable (const std::string &name, const std::string &clsname="") const
	Check if a user property is available for reading or not.
template<class T>
XAOD_AUXDATA_DEPRECATED bool	isAvailableWritable (const std::string &name, const std::string &clsname="") const
	Check if a user property is available for writing or not.

Detailed Description

Class describing a NeutralParticle.

Author

Andreas Salzburger Andre.nosp@m.as.S.nosp@m.alzbu.nosp@m.rger.nosp@m.@cern.nosp@m..ch

Definition at line 40 of file NeutralParticle_v1.h.

Member Typedef Documentation

FourMom_t

typedef IParticle::FourMom_t xAOD::NeutralParticle_v1::FourMom_t

Definition of the 4-momentum type.

Definition at line 69 of file NeutralParticle_v1.h.

GenVecFourMom_t

typedef ROOT::Math::LorentzVector<ROOT::Math::PxPyPzM4D<double> > xAOD::NeutralParticle_v1::GenVecFourMom_t

Base 4 Momentum type for TrackParticle.

Definition at line 75 of file NeutralParticle_v1.h.

Constructor & Destructor Documentation

NeutralParticle_v1() [1/2]

xAOD::NeutralParticle_v1::NeutralParticle_v1

(

)

Default constructor.

Definition at line 20 of file NeutralParticle_v1.cxx.

  : IParticle(){
  }

~NeutralParticle_v1()

xAOD::NeutralParticle_v1::~NeutralParticle_v1

(

)

Destructor.

Definition at line 40 of file NeutralParticle_v1.cxx.

                                         {
  }

NeutralParticle_v1() [2/2]

xAOD::NeutralParticle_v1::NeutralParticle_v1

(

const NeutralParticle_v1 &

o

)

Copy ctor. This involves copying the entire Auxilary store, and is a slow operation which should be used sparingly.

Definition at line 24 of file NeutralParticle_v1.cxx.

  : IParticle( tp ) {
    makePrivateStore( tp );
  }

Member Function Documentation

auxdata() [1/2]

template<class T>

XAOD_AUXDATA_DEPRECATED T & xAOD::IParticle::auxdata ( const std::string & name, const std::string & clsname = "" )

inlineinherited

Fetch an aux data variable, as a non-const reference.

This function provides an easy way for users to decorate objects with auxiliary data.

Take note that this function is slow. Should not be used inside time-critical code.

Parameters

name	Name of the aux variable
clsname	The name of the associated class. May be blank

Returns

A modifiable reference to the decoration

Definition at line 98 of file Event/xAOD/xAODBase/xAODBase/IParticle.h.

                                                {
 
         return SG::Accessor< T >(name, clsname)(*this);
      }

auxdata() [2/2]

template<class T>

XAOD_AUXDATA_DEPRECATED const T & xAOD::IParticle::auxdata ( const std::string & name, const std::string & clsname = "" ) const

inlineinherited

Fetch an aux data variable, as a const reference.

This function provides an easy way for users to retrieve auxiliary decorations from an object.

Take note that this function is slow. Should not be used inside time-critical code.

Parameters

name	Name of the aux variable
clsname	The name of the associated class. May be blank

Returns

A constant reference to the decoration

Definition at line 118 of file Event/xAOD/xAODBase/xAODBase/IParticle.h.

                                                            {
        
         return SG::ConstAccessor< T >( name, clsname )( *this );
      }

d0()

float xAOD::NeutralParticle_v1::d0

(

)

const

Returns the \(d_0\) parameter.

definingParameters()

const DefiningParameters_t xAOD::NeutralParticle_v1::definingParameters

(

)

const

Returns a SVector of the Perigee track parameters.

i.e. a vector of \(\left(\begin{array}{c}d_0\\z_0\\\phi_0\\\theta\\q/p\end{array}\right)\)

Definition at line 104 of file NeutralParticle_v1.cxx.

                                                                         {
      DefiningParameters_t tmp;
      tmp << d0(),z0(),phi0(),theta(),oneOverP();
      return tmp;
  }

definingParametersCovMatrix()

const xAOD::ParametersCovMatrix_t xAOD::NeutralParticle_v1::definingParametersCovMatrix

(

)

const

Returns the 5x5 symmetric matrix containing the defining parameters covariance matrix.

Definition at line 149 of file NeutralParticle_v1.cxx.

                                                                                        {
    static const Accessor< std::vector<float> > acc( "definingParametersCovMatrix" );
    std::vector<float> v = acc(*this);
    std::vector<float>::const_iterator it = v.begin();
    xAOD::ParametersCovMatrix_t cov;
    cov.setZero();
    for (size_t irow = 0; irow<5; ++irow){
        for (size_t icol =0; icol<=irow; ++icol){
            cov.fillSymmetric(icol,irow, *it++);
        }
    }
    return cov;
  }

definingParametersCovMatrixVec()

const std::vector< float > & xAOD::NeutralParticle_v1::definingParametersCovMatrixVec

(

)

const

Returns the vector of the covariance values - 15 elements.

Definition at line 163 of file NeutralParticle_v1.cxx.

                                                                                   {
    static const Accessor< std::vector<float> > acc( "definingParametersCovMatrix" );
    return acc(*this);
  }

e()

virtual double xAOD::NeutralParticle_v1::e ( ) const

virtual

The total energy of the particle.

Implements xAOD::IParticle.

eta()

double xAOD::NeutralParticle_v1::eta ( ) const

virtual

The pseudorapidity ( \(\eta\)) of the particle.

Implements xAOD::IParticle.

Definition at line 47 of file NeutralParticle_v1.cxx.

                                       {
    return genvecP4().Eta();
  }

genvecP4()

NeutralParticle_v1::GenVecFourMom_t xAOD::NeutralParticle_v1::genvecP4

(

)

const

The full 4-momentum of the particle : GenVector form.

Definition at line 65 of file NeutralParticle_v1.cxx.

                                                                       {
    using namespace std;
    float p = 1/fabs(oneOverP());
    float thetaT = theta();
    float phiT = phi();
    float sinTheta= sin(thetaT);
    float px = p*sinTheta*cos(phiT);
    float py = p*sinTheta*sin(phiT);
    float pz = p*cos(thetaT);
    return GenVecFourMom_t(px, py, pz, m());
  }

isAvailable()

template<class T>

XAOD_AUXDATA_DEPRECATED bool xAOD::IParticle::isAvailable ( const std::string & name, const std::string & clsname = "" ) const

inlineinherited

Check if a user property is available for reading or not.

This function should be used to check if a user property which may or may not exist, is set on the object.

Parameters

name	Name of the auxiliary variable
clsname	The name of the associated class. May be blank

Returns

Whether the decoration exists or not

Definition at line 135 of file Event/xAOD/xAODBase/xAODBase/IParticle.h.

                                                            {
 
         return SG::ConstAccessor< T >(name, clsname).isAvailable(*this);
      }

isAvailableWritable()

template<class T>

XAOD_AUXDATA_DEPRECATED bool xAOD::IParticle::isAvailableWritable ( const std::string & name, const std::string & clsname = "" ) const

inlineinherited

Check if a user property is available for writing or not.

This function can be used to check whether it will be possible to set a user property on the object.

Parameters

name	Name of the auxiliary variable
clsname	The name of the associated class. May be blank

Returns

Whether the decoration is possible to set

Definition at line 152 of file Event/xAOD/xAODBase/xAODBase/IParticle.h.

                                                                    {
 
         return SG::Accessor< T >(name, clsname).isAvailableWritable(*this);
      }

m()

double xAOD::NeutralParticle_v1::m ( ) const

virtual

The invariant mass of the particle..

Todo

Get value from somewhere. Also, the TrackParticle took the Pion mass - do we really want to do this? We have ParticleHypo?

Implements xAOD::IParticle.

Definition at line 54 of file NeutralParticle_v1.cxx.

                                     {
    return ParticleConstants::chargedPionMassInMeV; 
  }

oneOverP()

float xAOD::NeutralParticle_v1::oneOverP

(

)

const

Returns the \(q/p\) parameter.

operator=()

NeutralParticle_v1 & xAOD::NeutralParticle_v1::operator=

(

const NeutralParticle_v1 &

tp

)

Assignment operator. This can involve creating and copying an Auxilary store, and so should be used sparingly.

Definition at line 29 of file NeutralParticle_v1.cxx.

                                                                              {
    if(this == &tp) return *this;
 
    if(!hasStore() ) makePrivateStore();
    this->IParticle::operator=( tp );
#ifndef XAOD_ANALYSIS
    m_perigeeParameters.reset();
#endif // not XAOD_ANALYSIS
    return *this;
  }

p4()

NeutralParticle_v1::FourMom_t xAOD::NeutralParticle_v1::p4 ( ) const

virtual

The full 4-momentum of the particle.

Implements xAOD::IParticle.

Definition at line 77 of file NeutralParticle_v1.cxx.

                                                           {
    using namespace std;
    FourMom_t p4;
    float p = 1/fabs(oneOverP());
    float thetaT = theta();
    float phiT = phi();
    float sinTheta= sin(thetaT);
    float px = p*sinTheta*cos(phiT);
    float py = p*sinTheta*sin(phiT);
    float pz = p*cos(thetaT);
    float e  =  pow (m(),2) +
      pow( px,2) + pow( py,2) + pow( pz,2);
    p4.SetPxPyPzE( px, py, pz, sqrt(e) );
    return p4;
  }

perigeeParameters()

const Trk::NeutralPerigee & xAOD::NeutralParticle_v1::perigeeParameters

(

)

const

Returns the Trk::NeutralPerigee track parameters.

These are defined as: \(\left(\begin{array}{c}d_0\\z_0\\\phi_0\\\theta\\1/p\\\end{array}\right)\)

Note

This is only available in Athena.

Definition at line 189 of file NeutralParticle_v1.cxx.

                                                                       {
 
    // Require the cache to be valid and check if the cached pointer has been set
    if(m_perigeeParameters.isValid()){
          return *(m_perigeeParameters.ptr());
    }
    static const Accessor< float > acc1( "d0" );
    static const Accessor< float > acc2( "z0" );
    static const Accessor< float > acc3( "phi" );
    static const Accessor< float > acc4( "theta" );
    static const Accessor< float > acc5( "oneOverP" );
    static const Accessor< std::vector<float> > acc6( "definingParametersCovMatrix" );
    ParametersCovMatrix_t cov;
    cov.setZero();
    auto it= acc6(*this).begin();
    for (size_t irow = 0; irow<5; ++irow){
      for (size_t icol =0; icol<=irow; ++icol){
          cov.fillSymmetric(irow,icol,*it++) ;
      }
    }
    Trk::NeutralPerigee tmpPerigeeParameters(acc1(*this),acc2(*this),acc3(*this),acc4(*this),acc5(*this),
                                             Trk::PerigeeSurface(Amg::Vector3D(vx(),vy(),vz())),std::move(cov));
    m_perigeeParameters.set(tmpPerigeeParameters);
    return *(m_perigeeParameters.ptr());
  }

phi()

virtual double xAOD::NeutralParticle_v1::phi ( ) const

virtual

The azimuthal angle ( \(\phi\)) of the particle.

Implements xAOD::IParticle.

phi0()

float xAOD::NeutralParticle_v1::phi0

(

)

const

Returns the \(\phi\) parameter, which has range \(-\pi\) to \(+\pi\).

pt()

double xAOD::NeutralParticle_v1::pt ( ) const

virtual

The transverse momentum ( \(p_T\)) of the particle.

Implements xAOD::IParticle.

Definition at line 43 of file NeutralParticle_v1.cxx.

                                      {
    return genvecP4().Pt();
  }

rapidity()

double xAOD::NeutralParticle_v1::rapidity ( ) const

virtual

The true rapidity (y) of the particle.

Implements xAOD::IParticle.

Definition at line 61 of file NeutralParticle_v1.cxx.

                                            {
    return genvecP4().Rapidity();
  }

resetCache()

void xAOD::NeutralParticle_v1::resetCache

(

)

Reset the internal cache of the object.

Definition at line 216 of file NeutralParticle_v1.cxx.

                                      {
#ifndef XAOD_ANALYSIS
     m_perigeeParameters.reset();
#endif // not XAOD_ANALYSIS
  }

setDefiningParameters()

void xAOD::NeutralParticle_v1::setDefiningParameters	(	float	d0,
		float	z0,
		float	phi0,
		float	theta,
		float	qOverP )

Set the defining parameters.

Definition at line 110 of file NeutralParticle_v1.cxx.

                                                                                                            {
#ifndef XAOD_ANALYSIS
    if(m_perigeeParameters.isValid()) {
      m_perigeeParameters.reset();
    }
#endif // not XAOD_ANALYSIS
    static const Accessor< float > acc1( "d0" );
    acc1( *this ) = d0;
 
    static const Accessor< float > acc2( "z0" );
    acc2( *this ) = z0;
 
    static const Accessor< float > acc3( "phi" );
    acc3( *this ) = phi0;
 
    static const Accessor< float > acc4( "theta" );
    acc4( *this ) = theta;
 
    static const Accessor< float > acc5( "oneOverP" );
    acc5( *this ) = oneOverP;
 
    return;
  }

setDefiningParametersCovMatrix()

void xAOD::NeutralParticle_v1::setDefiningParametersCovMatrix

(

const ParametersCovMatrix_t &

cov

)

Set the defining parameters covariance matrix.

Definition at line 134 of file NeutralParticle_v1.cxx.

                                                                                             {
#ifndef XAOD_ANALYSIS
    if(m_perigeeParameters.isValid()) {
      m_perigeeParameters.reset();
    }
#endif // not XAOD_ANALYSIS
 
    static const Accessor< std::vector<float> > acc( "definingParametersCovMatrix" );
    std::vector<float>& v = acc(*this);
    v.reserve(15);
    for (size_t irow = 0; irow<5; ++irow)
        for (size_t icol =0; icol<=irow; ++icol)
            v.push_back(cov(icol,irow));
  }

setDefiningParametersCovMatrixVec()

void xAOD::NeutralParticle_v1::setDefiningParametersCovMatrixVec

(

const std::vector< float > &

cov

)

Set the defining parameters covariance matrix using a length 15 vector.

Definition at line 168 of file NeutralParticle_v1.cxx.

                                                                                       {
    static const Accessor< std::vector<float> > acc( "definingParametersCovMatrix" );
    acc(*this)=cov;
  }

setParametersOrigin()

void xAOD::NeutralParticle_v1::setParametersOrigin	(	float	x,
		float	y,
		float	z )

Set the origin for the parameters.

Definition at line 177 of file NeutralParticle_v1.cxx.

                                                                       {
    static const Accessor< float > acc1( "vx" );
    acc1( *this ) = x;
 
    static const Accessor< float > acc2( "vy" );
    acc2( *this ) = y;
 
    static const Accessor< float > acc3( "vz" );
    acc3( *this ) = z;
  }

theta()

float xAOD::NeutralParticle_v1::theta

(

)

const

Returns the \(\theta\) parameter, which has range 0 to \(\pi\).

type()

Type::ObjectType xAOD::NeutralParticle_v1::type ( ) const

virtual

The type of the object as a simple enumeration.

Implements xAOD::IParticle.

Definition at line 93 of file NeutralParticle_v1.cxx.

                                                {
     return Type::NeutralParticle;
  }

vx()

float xAOD::NeutralParticle_v1::vx

(

)

const

The x origin for the parameters.

vy()

float xAOD::NeutralParticle_v1::vy

(

)

const

The y origin for the parameters.

vz()

float xAOD::NeutralParticle_v1::vz

(

)

const

The z origin for the parameters.

z0()

float xAOD::NeutralParticle_v1::z0

(

)

const

Returns the \(z_0\) parameter.

Member Data Documentation

m_perigeeParameters

CxxUtils::CachedValue<Trk::NeutralPerigee> xAOD::NeutralParticle_v1::m_perigeeParameters

private

Cached NeutralPerigee, built from this object.

Note

This is only available in Athena.

Definition at line 144 of file NeutralParticle_v1.h.

---

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

• NeutralParticle_v1.h
• NeutralParticle_v1.cxx