ThePEG::Helicity::GeneralVVSVertex Class Reference

The GeneralVVSVertex class implements a general Vector-Vector-Scalar vertex allowing for decay modes that only enter at the one-loop level. More...

#include <GeneralVVSVertex.h>

Inheritance diagram for ThePEG::Helicity::GeneralVVSVertex:

List of all members.

Public Member Functions

GeneralVVSVertex ()

The default constructor.

virtual void setCoupling (Energy2 q2, tcPDPtr part1, tcPDPtr part2, tcPDPtr part3)=0

Calculate coupling.

virtual Complex evaluate (Energy2 q2, const VectorWaveFunction &vec1, const VectorWaveFunction &vec2, const ScalarWaveFunction &sca3)

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

virtual VectorWaveFunction evaluate (Energy2 q2, int iopt, tcPDPtr out, const VectorWaveFunction &vec2, const ScalarWaveFunction &sca3, Energy mass=-GeV, Energy width=-GeV)

Evaluate the off-shell vector coming from the vertex.

virtual ScalarWaveFunction evaluate (Energy2 q2, int iopt, tcPDPtr out, const VectorWaveFunction &vec1, const VectorWaveFunction &vec2, Energy mass=-GeV, Energy width=-GeV)

Evaluate the off-shell scalar coming from the vertex.

Set and Get tensor coefficients.

Complex a00 () const

Access coefficient of $g^{\mu\nu}$ .

Complex a11 () const

Access coefficient of $p_1^\mu p_1^\nu$ .

Complex a12 () const

Access coefficient of $p_1^\mu p_2^\nu$ .

Complex a21 () const

Access coefficient of $p_2^\mu p_1^\nu$ .

Complex a22 () const

Access coefficient of $p_2^\mu p_2^\nu$ .

Complex aEp () const

Access coefficient of $\epsilon^{\mu\nu\alpha\beta}p_1\alpha p_2\beta$ .

void a00 (const Complex &val)

Set tensor coefficient of $g^{\mu\nu}$ .

void a11 (const Complex &val)

Set tensor coefficient of $p_1^\mu p_1^\nu$ .

void a12 (const Complex &val)

Set tensor coefficient of $p_1^\mu p_2^\nu$ .

void a21 (const Complex &val)

Set tensor coefficient of $p_2^\mu p_1^\nu$ .

void a22 (const Complex &val)

Set tensor coefficient of $p_2^\mu p_2^\nu$ .

void aEp (const Complex &val)

Set tensor coefficient of $\epsilon^{\mu\nu\alpha\beta}p_1\alpha p_2\beta$ .

Static Public Member Functions

static void Init ()

The standard Init function used to initialize the interfaces.

Private Member Functions

GeneralVVSVertex & operator= (const GeneralVVSVertex &)

The assignment operator is private and must never be called.

Private Attributes

Store tensor coefficients.

Complex _a00

Coefficient of $g^{\mu\nu}$ .

Complex _a11

Coefficient of $p_1^\mu p_1^\nu$ .

Complex _a12

Coefficient of $p_1^\mu p_2^\nu$ .

Complex _a21

Coefficient of $p_2^\mu p_1^\nu$ .

Complex _a22

Coefficient of $p_2^\mu p_2^\nu$ .

Complex _aEp

Coefficient of $\epsilon^{\mu\nu\alpha\beta}p_1\alpha p_2\beta$ .

Static Private Attributes

static
AbstractNoPIOClassDescription
< GeneralVVSVertex > initGeneralVVSVertex

The static object used to initialize the description of this class.

Detailed Description

The GeneralVVSVertex class implements a general Vector-Vector-Scalar vertex allowing for decay modes that only enter at the one-loop level.

The loop integral is calculated by Passarino-Veltman reduction and the coefficients are stored here. They must be calculated in the inheriting class along with implementation of the setCoupling member.

The vertex takes the form

$a_{00}g^{\mu\nu}p_1\cdot p_2 + a_{11}p_1^\mu p_1^\nu + a_{12}p_1^\mu p_2^\nu + a_{21}p_2^\mu p_1^\nu + a_{22}p_2^\mu p_2^\nu +a_e\epsilon^{p_1 \mu \nu p_2}$

Definition at line 34 of file GeneralVVSVertex.h.

Member Function Documentation

static void ThePEG::Helicity::GeneralVVSVertex::Init ( ) [static]

The standard Init function used to initialize the interfaces.

Called exactly once for each class by the class description system before the main function starts or when this class is dynamically loaded.

Reimplemented from ThePEG::Helicity::AbstractVVSVertex.

virtual Complex ThePEG::Helicity::GeneralVVSVertex::evaluate	(	Energy2	q2,
		const VectorWaveFunction &	vec1,
		const VectorWaveFunction &	vec2,
		const ScalarWaveFunction &	sca3
	)			`[virtual]`

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

Evaluate the vertex.

Parameters:

	q2	The scale for the coupling at the vertex.
	vec1	The wavefunction for the first vector.
	vec2	The wavefunction for the second vector.
	sca3	The wavefunction for the scalar.

Implements ThePEG::Helicity::AbstractVVSVertex.

virtual VectorWaveFunction ThePEG::Helicity::GeneralVVSVertex::evaluate	(	Energy2	q2,
		int	iopt,
		tcPDPtr	out,
		const VectorWaveFunction &	vec2,
		const ScalarWaveFunction &	sca3,
		Energy	mass = `-GeV`,
		Energy	width = `-GeV`
	)			`[virtual]`

Evaluate the off-shell vector coming from the vertex.

Parameters:

	q2	The scale 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.
	vec2	The wavefunction for the vector.
	sca3	The wavefunction for the scalar.
	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::AbstractVVSVertex.

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

Evaluate the off-shell scalar coming from the vertex.

Parameters:

	q2	The scale for the coupling at the vertex.
	iopt	Option of the shape of the Breit-Wigner for the off-shell scalar.
	out	The ParticleData pointer for the off-shell scalar.
	vec1	The wavefunction for the first vector.
	vec2	The wavefunction for the second 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::AbstractVVSVertex.

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

Calculate coupling.

Parameters:

	q2	Scale at which to evaluate couplings
	part1	ParticleDataPointer to first particle
	part2	ParticleDataPointer to second particle
	part3	ParticleDataPointer to third particle

GeneralVVSVertex& ThePEG::Helicity::GeneralVVSVertex::operator= ( const GeneralVVSVertex & ) [private]

The assignment operator is private and must never be called.

In fact, it should not even be implemented.

Member Data Documentation

AbstractNoPIOClassDescription<GeneralVVSVertex> ThePEG::Helicity::GeneralVVSVertex::initGeneralVVSVertex [static, private]

The static object used to initialize the description of this class.

Indicates that this is an abstract class without persistent data.

Definition at line 189 of file GeneralVVSVertex.h.

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

GeneralVVSVertex.h


Public Member Functions
	GeneralVVSVertex ()
	The default constructor.
virtual void	setCoupling (Energy2 q2, tcPDPtr part1, tcPDPtr part2, tcPDPtr part3)=0
	Calculate coupling.

virtual Complex	evaluate (Energy2 q2, const VectorWaveFunction &vec1, const VectorWaveFunction &vec2, const ScalarWaveFunction &sca3)
	Members to calculate the helicity amplitude expressions for vertices and off-shell particles.
virtual VectorWaveFunction	evaluate (Energy2 q2, int iopt, tcPDPtr out, const VectorWaveFunction &vec2, const ScalarWaveFunction &sca3, Energy mass=-GeV, Energy width=-GeV)
	Evaluate the off-shell vector coming from the vertex.
virtual ScalarWaveFunction	evaluate (Energy2 q2, int iopt, tcPDPtr out, const VectorWaveFunction &vec1, const VectorWaveFunction &vec2, Energy mass=-GeV, Energy width=-GeV)
	Evaluate the off-shell scalar coming from the vertex.
Set and Get tensor coefficients.
Complex	a00 () const
	Access coefficient of $g^{\mu\nu}$ .
Complex	a11 () const
	Access coefficient of $p_1^\mu p_1^\nu$ .
Complex	a12 () const
	Access coefficient of $p_1^\mu p_2^\nu$ .
Complex	a21 () const
	Access coefficient of $p_2^\mu p_1^\nu$ .
Complex	a22 () const
	Access coefficient of $p_2^\mu p_2^\nu$ .
Complex	aEp () const
	Access coefficient of $\epsilon^{\mu\nu\alpha\beta}p_1\alpha p_2\beta$ .
void	a00 (const Complex &val)
	Set tensor coefficient of $g^{\mu\nu}$ .
void	a11 (const Complex &val)
	Set tensor coefficient of $p_1^\mu p_1^\nu$ .
void	a12 (const Complex &val)
	Set tensor coefficient of $p_1^\mu p_2^\nu$ .
void	a21 (const Complex &val)
	Set tensor coefficient of $p_2^\mu p_1^\nu$ .
void	a22 (const Complex &val)
	Set tensor coefficient of $p_2^\mu p_2^\nu$ .
void	aEp (const Complex &val)
	Set tensor coefficient of $\epsilon^{\mu\nu\alpha\beta}p_1\alpha p_2\beta$ .
Static Public Member Functions
static void	Init ()
	The standard Init function used to initialize the interfaces.
Private Member Functions
GeneralVVSVertex &	operator= (const GeneralVVSVertex &)
	The assignment operator is private and must never be called.
Private Attributes
Store tensor coefficients.
Complex	_a00
	Coefficient of $g^{\mu\nu}$ .
Complex	_a11
	Coefficient of $p_1^\mu p_1^\nu$ .
Complex	_a12
	Coefficient of $p_1^\mu p_2^\nu$ .
Complex	_a21
	Coefficient of $p_2^\mu p_1^\nu$ .
Complex	_a22
	Coefficient of $p_2^\mu p_2^\nu$ .
Complex	_aEp
	Coefficient of $\epsilon^{\mu\nu\alpha\beta}p_1\alpha p_2\beta$ .
Static Private Attributes
static AbstractNoPIOClassDescription < GeneralVVSVertex >	initGeneralVVSVertex
	The static object used to initialize the description of this class.