ThePEG::Helicity::VVVTVertex Class Reference

The VVTVertex class is the implementation of the vector-vector-vector-tensor vertex. More...

#include <VVVTVertex.h>

Inheritance diagram for ThePEG::Helicity::VVVTVertex:

ThePEG::Helicity::AbstractVVVTVertex 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, tcPDPtr part4)=0
 Calculate the couplings.
Complex evaluate (Energy2 q2, const VectorWaveFunction &vec1, const VectorWaveFunction &vec2, const VectorWaveFunction &vec3, const TensorWaveFunction &ten4)
 Members to calculate the helicity amplitude expressions for vertices and off-shell particles.
TensorWaveFunction evaluate (Energy2 q2, int iopt, tcPDPtr out, const VectorWaveFunction &vec1, const VectorWaveFunction &vec2, const VectorWaveFunction &vec3, Energy mass=-GeV, Energy width=-GeV)
 Evaluate the off-shell tensor coming from the vertex.
VectorWaveFunction evaluate (Energy2 q2, int iopt, tcPDPtr out, const VectorWaveFunction &vec1, const VectorWaveFunction &vec2, const TensorWaveFunction &ten4, Energy mass=-GeV, Energy width=-GeV)
 Evaluate the off-shell vector coming from the vertex.

Static Public Member Functions

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

Private Member Functions

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

Static Private Attributes

static
AbstractNoPIOClassDescription
< VVVTVertex > 		initVVVTVertex
 Describe an abstract base class with persistent data.

Detailed Description

The VVTVertex class is the implementation of the vector-vector-vector-tensor vertex.

It inherits from the AbstractVVVTVertex class for the storage of the particles interacting at the vertex and implements the helicity amplitude calculations.

All implementations of this vertex should inherit from it and implement the virtual setCoupling member.

The vertex has the form

\[ g\frac\kappa2f^{abc}\left[ C_{\mu\nu,\rho\sigma}(k_1-k_2)_\lambda+C_{\mu\nu,\rho\lambda}(k_3-k_1)_\sigma +C_{\mu\nu,\sigma\lambda}(k_2-k_3)_\rho+F_{\mu\nu,\rho\sigma\lambda} \right]\epsilon_1^\rho\epsilon^\sigma_2\epsilon^\lambda_3 \epsilon^{\mu\nu}_4 \]

where -$C_{\mu\nu,\rho\sigma}=g_{\mu\rho}g_{\nu\sigma}+g_{\mu\sigma}g_{\nu\rho} -g_{\mu\nu}g_{\rho\sigma}$ -$F_{\mu\nu,\rho\sigma\lambda} = g_{\mu\rho}g_{\sigma\lambda}(k_2-k_3)_\nu +g_{\mu\sigma}g_{\rho\lambda}(k_3-k_1)_\nu +g_{\mu\lambda}g_{\rho\sigma}(k_1-k_2)_\nu+(\mu\leftrightarrow\nu) $

See also:
AbstractVVVTVertex

Definition at line 51 of file VVVTVertex.h.

Member Function Documentation

Complex ThePEG::Helicity::VVVTVertex::evaluate ( Energy2  q2,
const VectorWaveFunction &  vec1,
const VectorWaveFunction &  vec2,
const VectorWaveFunction &  vec3,
const TensorWaveFunction &  ten4 
) [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.
vec1 The wavefunction for the first vector.
vec2 The wavefunction for the second vector.
vec3 The wavefunction for the third vector.
ten4 The wavefunction for the tensor.

Implements ThePEG::Helicity::AbstractVVVTVertex.

TensorWaveFunction ThePEG::Helicity::VVVTVertex::evaluate ( Energy2  q2,
int  iopt,
tcPDPtr  out,
const VectorWaveFunction &  vec1,
const VectorWaveFunction &  vec2,
const VectorWaveFunction &  vec3,
Energy  mass = -GeV,
Energy  width = -GeV 
) [virtual]

Evaluate the off-shell tensor 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 tensor.
out The ParticleData pointer for the off-shell tensor.
vec1 The wavefunction for the first vector.
vec2 The wavefunction for the second vector.
vec3 The wavefunction for the third 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::AbstractVVVTVertex.

VectorWaveFunction ThePEG::Helicity::VVVTVertex::evaluate ( Energy2  q2,
int  iopt,
tcPDPtr  out,
const VectorWaveFunction &  vec1,
const VectorWaveFunction &  vec2,
const TensorWaveFunction &  ten4,
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.
vec1 The wavefunction for the first vector.
vec2 The wavefunction for the second vector.
ten4 The wavefunction for the tensor.
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::AbstractVVVTVertex.

virtual void ThePEG::Helicity::VVVTVertex::setCoupling ( Energy2  q2,
tcPDPtr  part1,
tcPDPtr  part2,
tcPDPtr  part3,
tcPDPtr  part4 
) [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.
part4 The ParticleData pointer for the fourth particle.

The documentation for this class was generated from the following file:
Generated on Thu Apr 29 12:43:30 2010 for ThePEG by  doxygen 1.5.5