ThePEG::Helicity::FFVVertex Class Reference

The FFVVertex class is the base class for all helicity amplitude vertices which use the renormalisable form for the fermion-fermion-vector vertex. More...

#include <FFVVertex.h>

Inheritance diagram for ThePEG::Helicity::FFVVertex:

ThePEG::Helicity::AbstractFFVVertex ThePEG::Helicity::VertexBase ThePEG::Interfaced ThePEG::InterfacedBase ThePEG::Base ThePEG::Named ThePEG::Pointer::ReferenceCounted

List of all members.

Public Member Functions

virtual void setCoupling (Energy2 q2, tcPDPtr part1, tcPDPtr part2, tcPDPtr part3)=0
 Calculate the couplings.
Complex evaluate (Energy2 q2, const SpinorWaveFunction &sp1, const SpinorBarWaveFunction &sbar2, const VectorWaveFunction &vec3)
 Members to calculate the helicity amplitude expressions for vertices and off-shell particles.
SpinorBarWaveFunction evaluate (Energy2 q2, int iopt, tcPDPtr out, const SpinorBarWaveFunction &sbar2, const VectorWaveFunction &vec3, Energy mass=-GeV, Energy width=-GeV)
 Evaluate the off-shell barred spinor coming from the vertex.
VectorWaveFunction evaluate (Energy2 q2, int iopt, tcPDPtr out, const SpinorWaveFunction &sp1, const SpinorBarWaveFunction &sbar2, Energy mass=-GeV, Energy width=-GeV)
 Evaluate the off-shell vector coming from the vertex.
SpinorWaveFunction evaluate (Energy2 q2, int iopt, tcPDPtr out, const SpinorWaveFunction &sp1, const VectorWaveFunction &vec3, Energy mass=-GeV, Energy width=-GeV)
 Evaluate the off-shell spinor coming from the vertex.
virtual SpinorWaveFunction evaluateSmall (Energy2 q2, int iopt, tcPDPtr out, const SpinorWaveFunction &sp1, const VectorWaveFunction &vec3, unsigned int fhel, unsigned int vhel, double ctheta, double phi, double stheta, bool includeEikonal=true, SmallAngleDirection direction=PostiveZDirection, Energy mass=-GeV, Energy width=-GeV)
 Special members for off-shell fermion wavefunctions with massless gauge bosons at small angles in the small angle limit for numerical accuracy.
virtual SpinorBarWaveFunction evaluateSmall (Energy2 q2, int iopt, tcPDPtr out, const SpinorBarWaveFunction &sbar2, const VectorWaveFunction &vec3, unsigned int fhel, unsigned int vhel, double ctheta, double phi, double stheta, bool includeEikonal=true, SmallAngleDirection direction=PostiveZDirection, Energy mass=-GeV, Energy width=-GeV)
 Small angle approx for an off-shell spinor.
const Complex & left ()
 Get the Couplings.
const Complex & right ()
 Get the right coupling.

Static Public Member Functions

static void Init ()
 Standard Init function used to initialize the interfaces.

Protected Member Functions

void left (const Complex &in)
 Set the couplings.
void right (const Complex &in)
 Set the right coupling.

Private Member Functions

FFVVertex & operator= (const FFVVertex &)
 Private and non-existent assignment operator.

Private Attributes

Complex _left
 Left coupling.
Complex _right
 Right coupling.

Static Private Attributes

static
AbstractNoPIOClassDescription
< FFVVertex > 		initFFVVertex
 Describe an abstract class with persistent data.

Detailed Description

The FFVVertex class is the base class for all helicity amplitude vertices which use the renormalisable form for the fermion-fermion-vector vertex.

Any such vertices should inherit from this class and implement the virtual setcoupling member function. The base AbstractFFVVertex class is used to store the particles allowed to interact at the vertex.

The form of the vertex is

\[ic\bar{f_2}\gamma^\mu a^\lambda P_\lambda f_1\epsilon_{3\mu}\]

See also:
AbstractFFVVertex

Definition at line 39 of file FFVVertex.h.

Member Function Documentation

Complex ThePEG::Helicity::FFVVertex::evaluate ( Energy2  q2,
const SpinorWaveFunction &  sp1,
const SpinorBarWaveFunction &  sbar2,
const VectorWaveFunction &  vec3 
) [virtual]

Members to calculate the helicity amplitude expressions for vertices and off-shell particles.

Evalulate the vertex.

Parameters:
q2 The scale $q^2$ for the coupling at the vertex.
sp1 The wavefunction for the ferimon.
sbar2 The wavefunction for the antifermion.
vec3 The wavefunction for the vector.

Implements ThePEG::Helicity::AbstractFFVVertex.

SpinorBarWaveFunction ThePEG::Helicity::FFVVertex::evaluate ( Energy2  q2,
int  iopt,
tcPDPtr  out,
const SpinorBarWaveFunction &  sbar2,
const VectorWaveFunction &  vec3,
Energy  mass = -GeV,
Energy  width = -GeV 
) [virtual]

Evaluate the off-shell barred spinor coming from the vertex.

Parameters:
q2 The scale $q^2$ for the coupling at the vertex.
iopt Option of the shape of the Breit-Wigner for the off-shell barred spinor.
out The ParticleData pointer for the off-shell barred spinor.
sbar2 The wavefunction for the antifermion.
vec3 The wavefunction for the vector.
mass The mass of the off-shell particle if not taken from the ParticleData object
width The width of the off-shell particle if not taken from the ParticleData object

Implements ThePEG::Helicity::AbstractFFVVertex.

VectorWaveFunction ThePEG::Helicity::FFVVertex::evaluate ( Energy2  q2,
int  iopt,
tcPDPtr  out,
const SpinorWaveFunction &  sp1,
const SpinorBarWaveFunction &  sbar2,
Energy  mass = -GeV,
Energy  width = -GeV 
) [virtual]

Evaluate the off-shell vector coming from the vertex.

Parameters:
q2 The scale $q^2$ for the coupling at the vertex.
iopt Option of the shape of the Breit-Wigner for the off-shell vector.
out The ParticleData pointer for the off-shell vector.
sp1 The wavefunction for the ferimon.
sbar2 The wavefunction for the antifermion.
mass The mass of the off-shell particle if not taken from the ParticleData object
width The width of the off-shell particle if not taken from the ParticleData object

Implements ThePEG::Helicity::AbstractFFVVertex.

SpinorWaveFunction ThePEG::Helicity::FFVVertex::evaluate ( Energy2  q2,
int  iopt,
tcPDPtr  out,
const SpinorWaveFunction &  sp1,
const VectorWaveFunction &  vec3,
Energy  mass = -GeV,
Energy  width = -GeV 
) [virtual]

Evaluate the off-shell spinor coming from the vertex.

Parameters:
q2 The scale $q^2$ for the coupling at the vertex.
iopt Option of the shape of the Breit-Wigner for the off-shell spinor.
out The ParticleData pointer for the off-shell spinor.
sp1 The wavefunction for the ferimon.
vec3 The wavefunction for the vector.
mass The mass of the off-shell particle if not taken from the ParticleData object
width The width of the off-shell particle if not taken from the ParticleData object

Implements ThePEG::Helicity::AbstractFFVVertex.

virtual SpinorWaveFunction ThePEG::Helicity::FFVVertex::evaluateSmall ( Energy2  q2,
int  iopt,
tcPDPtr  out,
const SpinorWaveFunction &  sp1,
const VectorWaveFunction &  vec3,
unsigned int  fhel,
unsigned int  vhel,
double  ctheta,
double  phi,
double  stheta,
bool  includeEikonal = true,
SmallAngleDirection  direction = PostiveZDirection,
Energy  mass = -GeV,
Energy  width = -GeV 
) [virtual]

Special members for off-shell fermion wavefunctions with massless gauge bosons at small angles in the small angle limit for numerical accuracy.

In order to get sufficient accuracy it is assumed that the fermion lies along either the positive or negative z axis. Small angle approx for an off-shell spinor

Parameters:
q2 The scale $q^2$ for the coupling at the vertex.
iopt Option of the shape of the Breit-Wigner for the off-shell spinor.
out The ParticleData pointer for the off-shell spinor.
sp1 The wavefunction for the ferimon.
vec3 The wavefunction for the vector.
fhel Helicity of the fermion
vhel Helicity of the vector
ctheta The cosine of the polar angle of the photon with respect to the fermion
phi The azimuthal angle of the photon with respect to the fermion
stheta The sine of the polar angle of the photon with respect to the fermion
includeEikonal Whether or not to include the eikonal piece
direction Whether fermion along + or - z direction
mass The mass of the off-shell particle if not taken from the ParticleData object
width The width of the off-shell particle if not taken from the ParticleData object

Reimplemented from ThePEG::Helicity::AbstractFFVVertex.

virtual SpinorBarWaveFunction ThePEG::Helicity::FFVVertex::evaluateSmall ( Energy2  q2,
int  iopt,
tcPDPtr  out,
const SpinorBarWaveFunction &  sbar2,
const VectorWaveFunction &  vec3,
unsigned int  fhel,
unsigned int  vhel,
double  ctheta,
double  phi,
double  stheta,
bool  includeEikonal = true,
SmallAngleDirection  direction = PostiveZDirection,
Energy  mass = -GeV,
Energy  width = -GeV 
) [virtual]

Small angle approx for an off-shell spinor.

Parameters:
q2 The scale $q^2$ for the coupling at the vertex.
iopt Option of the shape of the Breit-Wigner for the off-shell spinor.
out The ParticleData pointer for the off-shell spinor.
sbar2 The wavefunction for the antifermion.
vec3 The wavefunction for the vector.
fhel Helicity of the fermion
vhel Helicity of the vector
ctheta The cosine of the polar angle of the photon with respect to the fermion
phi The azimuthal angle of the photon with respect to the fermion
stheta The sine of the polar angle of the photon with respect to the fermion
includeEikonal Whether or not to include the eikonal piece
direction Whether fermion along + or - z direction
mass The mass of the off-shell particle if not taken from the ParticleData object
width The width of the off-shell particle if not taken from the ParticleData object

Reimplemented from ThePEG::Helicity::AbstractFFVVertex.

virtual void ThePEG::Helicity::FFVVertex::setCoupling ( Energy2  q2,
tcPDPtr  part1,
tcPDPtr  part2,
tcPDPtr  part3 
) [pure virtual]

Calculate the couplings.

This method is virtual and must be implemented in classes inheriting from this.

Parameters:
q2 The scale $q^2$ for the coupling at the vertex.
part1 The ParticleData pointer for the first particle.
part2 The ParticleData pointer for the second particle.
part3 The ParticleData pointer for the third particle.

const Complex& ThePEG::Helicity::FFVVertex::left (  )  [inline]

Get the Couplings.

Get the left coupling.

Definition at line 201 of file FFVVertex.h.

References _left.

void ThePEG::Helicity::FFVVertex::left ( const Complex &  in  )  [inline, protected]

Set the couplings.

Set the left coupling.

Definition at line 218 of file FFVVertex.h.

References _left.

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