ThePEG::Helicity::VertexBase Class Reference

The VertexBase class is the base class for all helicity amplitude vertices. More...

#include <VertexBase.h>

Inheritance diagram for ThePEG::Helicity::VertexBase:

List of all members.

Public Member Functions

Standard constructors and destructors.

VertexBase (VertexType::T name, bool kine=false)

Constructor for $n$ -point vertices.

Functions used by the persistent I/O system.

void persistentOutput (PersistentOStream &os) const

Function used to write out object persistently.

void persistentInput (PersistentIStream &is, int version)

Function used to read in object persistently.

unsigned int size () const

Access to the particle information.

bool isIncoming (tPDPtr p) const

Is a particle allowed as an incoming particle?

bool isOutgoing (tPDPtr p) const

Is a particle allowed as an outgoing particle?

const set< tPDPtr > & incoming () const

Get the list of incoming particles.

const set< tPDPtr > & outgoing () const

Get the list of outgoing particles.

Complex norm () const

Get the coupling.

vector< long > search (unsigned int ilist, long id) const

Function to search the list.

vector< tPDPtr > search (unsigned int ilist, tcPDPtr id) const

Function to search the list.

bool allowed (long id1, long id2, long id3, long id4=0) const

Is a given combination allowed.

VertexType::T getName () const

Get name of Vertex.

unsigned int getNpoint () const

Get number of lines on Vertex.

unsigned int orderInGem () const

Get the order in $g_EM$ .

unsigned int orderInGs () const

Get the order in $g_s$ .

Kinematic invariants for loop diagrams

bool kinematics () const

Whether or not to calculate the kinematics invariants.

void kinematics (bool kine)

Set whether or not to calculate the kinematics invariants.

void calculateKinematics (const Lorentz5Momentum &p0, const Lorentz5Momentum &p2, const Lorentz5Momentum &p1)

Calculate the kinematics for a 3-point vertex.

void calculateKinematics (const Lorentz5Momentum &p0, const Lorentz5Momentum &p1, const Lorentz5Momentum &p2, const Lorentz5Momentum &p3)

Calculate the kinematics for a 4-point vertex.

void calculateKinematics (const vector< Lorentz5Momentum > &p)

Calculate the kinematics for a n-point vertex.

Energy2 invariant (unsigned int ix, unsigned int iy) const

Get one of the kinematic invariants.

Static Public Member Functions

static void Init ()

Standard Init function used to initialize the interfaces.

Protected Member Functions

void orderInGem (unsigned int order)

Set the order in $g_EM$ .

void orderInGs (unsigned int order)

Set the order in $g_s$ .

Calculation of the strong, electromagnetic and weak couplings

double strongCoupling (Energy2 q2) const

Strong coupling.

double electroMagneticCoupling (Energy2 q2) const

Electromagnetic coupling.

double weakCoupling (Energy2 q2) const

Weak coupling.

double sin2ThetaW () const

Standard Interfaced functions.

virtual void doinit ()

Initialize this object after the setup phase before saving an EventGenerator to disk.

virtual void rebind (const TranslationMap &trans)

Rebind pointer to other Interfaced objects.

virtual IVector getReferences ()

Return a vector of all pointers to Interfaced objects used in this object.

void addToList (const vector< long > &ids)

Members to set-up the particles.

void addToList (long ida, long idb, long idc, long idd=0)

Set up the lists of outer particles for the three-/four-point vertex.

void norm (const Complex &coup)

Members for the amplitude calculations.

virtual Complex propagator (int iopt, Energy2 q2, tcPDPtr part, Energy mass=-GeV, Energy width=-GeV)

Calculate the propagator for a diagram.

Complex normPropagator (int iopt, Energy2 q2, tcPDPtr part, Energy mass=-GeV, Energy width=-GeV)

Calculate propagator multiplied by coupling.

Private Member Functions

VertexBase & operator= (const VertexBase &)

Private and non-existent assignment operator.

Private Attributes

Complex _norm

The overall coupling.

bool _calckinematics

Whether or not to calculate the kinematic invariants for the vertex.

vector< vector< Energy2 > > _kine

Kinematica quantities needed for loop vertices.

VertexType::T _theName

Name of vertex.

unsigned int _ordergEM

Order of vertex in $g_EM$ .

unsigned int _ordergS

Order of vertex in $g_s$ .

unsigned int _coupopt

option for the coupling

double _gs

Fixed value of strong coupling to use.

double _ee

Fixed value of the electromagentic coupling to use.

double _sw

Fixed value of $\sin\theta_W$ to use.

vector< vector< PDPtr > > _particles

Storage of the particles.

unsigned int _npoint

Number of particles at the vertex.

set< tPDPtr > _inpart

ParticleData pointers for the allowed incoming particles.

set< tPDPtr > _outpart

ParticleData pointers for the allowed outgoing particles.

Static Private Attributes

static
AbstractClassDescription
< ThePEG::Helicity::VertexBase > initVertexBase

Describe a concrete class with persistent data.

Friends

ostream & operator<< (ostream &, const VertexBase &)

The output operator is a friend to avoid the data being public.

Detailed Description

The VertexBase class is the base class for all helicity amplitude vertices.

In implements the storage of the particles which are allowed to interact at the vertex and some simple functions which are often needed by the classes which implement the specific vertices.

In practice little use is made of this information and it is mainly included for future extensions. It can also be used at the development and debugging stage.

Definition at line 46 of file VertexBase.h.

Constructor & Destructor Documentation

ThePEG::Helicity::VertexBase::VertexBase	(	VertexType::T	name,
		bool	kine = `false`
	)

Constructor for $n$ -point vertices.

Parameters:

	npoint	The number of external particles.
	kine	Whether the kinematic invariants should be calculated.

Member Function Documentation

void ThePEG::Helicity::VertexBase::persistentOutput ( PersistentOStream & os ) const

Function used to write out object persistently.

Parameters:

os

the persistent output stream written to.

Reimplemented from ThePEG::Interfaced.

void ThePEG::Helicity::VertexBase::persistentInput	(	PersistentIStream &	is,
		int	version
	)

Function used to read in object persistently.

Parameters:

	is	the persistent input stream read from.
	version	the version number of the object when written.

Reimplemented from ThePEG::Interfaced.

unsigned int ThePEG::Helicity::VertexBase::size ( ) const [inline]

Access to the particle information.

Number of different particle combinations allowed.

Definition at line 96 of file VertexBase.h.

References _particles.

bool ThePEG::Helicity::VertexBase::isIncoming ( tPDPtr p ) const [inline]

Is a particle allowed as an incoming particle?

Parameters:

p

The ParticleData pointer

Definition at line 103 of file VertexBase.h.

References _inpart.

bool ThePEG::Helicity::VertexBase::isOutgoing ( tPDPtr p ) const [inline]

Is a particle allowed as an outgoing particle?

Parameters:

p

The ParticleData pointer

Definition at line 111 of file VertexBase.h.

References _outpart.

vector<long> ThePEG::Helicity::VertexBase::search	(	unsigned int	ilist,
		long	id
	)			const

Function to search the list.

Parameters:

	ilist	Which list to search
	id	The PDG code to look for.

vector<tPDPtr> ThePEG::Helicity::VertexBase::search	(	unsigned int	ilist,
		tcPDPtr	id
	)			const

Function to search the list.

Parameters:

	ilist	Which list to search
	id	The particle to look for.

bool ThePEG::Helicity::VertexBase::allowed	(	long	id1,
		long	id2,
		long	id3,
		long	id4 = `0`
	)			const

Is a given combination allowed.

Parameters:

	id1	PDG code of the first particle.
	id2	PDG code of the second particle.
	id3	PDG code of the third particle.
	id4	PDG code of the fourth particle.

virtual void ThePEG::Helicity::VertexBase::doinit ( ) [protected, virtual]

Initialize this object after the setup phase before saving an EventGenerator to disk.

Exceptions:

InitException

if object could not be initialized properly.

Reimplemented from ThePEG::InterfacedBase.

virtual void ThePEG::Helicity::VertexBase::rebind ( const TranslationMap & trans ) [protected, virtual]

Rebind pointer to other Interfaced objects.

Called in the setup phase after all objects used in an EventGenerator has been cloned so that the pointers will refer to the cloned objects afterwards.

Parameters:

trans

a TranslationMap relating the original objects to their respective clones.

Exceptions:

RebindException

if no cloned object was found for a given pointer.

Reimplemented from ThePEG::InterfacedBase.

virtual IVector ThePEG::Helicity::VertexBase::getReferences ( ) [protected, virtual]

Return a vector of all pointers to Interfaced objects used in this object.

Returns:: a vector of pointers.

Reimplemented from ThePEG::InterfacedBase.

void ThePEG::Helicity::VertexBase::addToList ( const vector< long > & ids ) [protected]

Members to set-up the particles.

Set up the lists of outer particles for the vertex.

Parameters:

	ids	A vector of PDG codes for the particles.
	idb	The PDG codes for the second set of particles.
	idc	The PDG codes for the third set of particles.
	idd	The PDG codes for the fourth set of particles.

void ThePEG::Helicity::VertexBase::addToList	(	long	ida,
		long	idb,
		long	idc,
		long	idd = `0`
	)			`[protected]`

Set up the lists of outer particles for the three-/four-point vertex.

For small vertices, this form is much easier to use.

Parameters:

	ida	The PDG codes for the first set of particles.
	idb	The PDG codes for the second set of particles.
	idc	The PDG codes for the third set of particles.
	idd	The PDG codes for the fourth set of particles.

void ThePEG::Helicity::VertexBase::norm ( const Complex & coup ) [inline, protected]

Members for the amplitude calculations.

Set the coupling.

Parameters:

coup

The coupling.

Definition at line 290 of file VertexBase.h.

References _norm.

virtual Complex ThePEG::Helicity::VertexBase::propagator	(	int	iopt,
		Energy2	q2,
		tcPDPtr	part,
		Energy	mass = `-GeV`,
		Energy	width = `-GeV`
	)			`[protected, virtual]`

Calculate the propagator for a diagram.

Parameters:

	iopt	The option for the Breit-Wigner shape
	q2	The scale
	part	The ParticleData pointer for the off-shell particle.
	mass	The mass if not to be taken from the ParticleData object
	width	The width if not to be taken from the ParticleData object

Referenced by normPropagator().

Complex ThePEG::Helicity::VertexBase::normPropagator	(	int	iopt,
		Energy2	q2,
		tcPDPtr	part,
		Energy	mass = `-GeV`,
		Energy	width = `-GeV`
	)			`[inline, protected]`

Calculate propagator multiplied by coupling.

Parameters:

	iopt	The option for the Breit-Wigner shape
	q2	The scale
	part	The ParticleData pointer for the off-shell particle.
	mass	The mass if not to be taken from the ParticleData object
	width	The width if not to be taken from the ParticleData object

Definition at line 311 of file VertexBase.h.

References _norm, and propagator().

void ThePEG::Helicity::VertexBase::orderInGem ( unsigned int order ) [inline, protected]

Set the order in $g_EM$ .

Parameters:

order

The order of the vertex in $g_EM$

Definition at line 392 of file VertexBase.h.

References _ordergEM.

void ThePEG::Helicity::VertexBase::orderInGs ( unsigned int order ) [inline, protected]

Set the order in $g_s$ .

Parameters:

order

The order of the vertex in $g_s$

Definition at line 398 of file VertexBase.h.

References _ordergS.

Member Data Documentation

vector<vector<PDPtr> > ThePEG::Helicity::VertexBase::_particles [private]

Storage of the particles.

Particles interacting at the vertex

Definition at line 421 of file VertexBase.h.

Referenced by size().

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

VertexBase.h


Public Member Functions
Standard constructors and destructors.
	VertexBase (VertexType::T name, bool kine=false)
	Constructor for -point vertices.
Functions used by the persistent I/O system.
void	persistentOutput (PersistentOStream &os) const
	Function used to write out object persistently.
void	persistentInput (PersistentIStream &is, int version)
	Function used to read in object persistently.

unsigned int	size () const
	Access to the particle information.
bool	isIncoming (tPDPtr p) const
	Is a particle allowed as an incoming particle?
bool	isOutgoing (tPDPtr p) const
	Is a particle allowed as an outgoing particle?
const set< tPDPtr > &	incoming () const
	Get the list of incoming particles.
const set< tPDPtr > &	outgoing () const
	Get the list of outgoing particles.
Complex	norm () const
	Get the coupling.
vector< long >	search (unsigned int ilist, long id) const
	Function to search the list.
vector< tPDPtr >	search (unsigned int ilist, tcPDPtr id) const
	Function to search the list.
bool	allowed (long id1, long id2, long id3, long id4=0) const
	Is a given combination allowed.
VertexType::T	getName () const
	Get name of Vertex.
unsigned int	getNpoint () const
	Get number of lines on Vertex.
unsigned int	orderInGem () const
	Get the order in .
unsigned int	orderInGs () const
	Get the order in .
Kinematic invariants for loop diagrams
bool	kinematics () const
	Whether or not to calculate the kinematics invariants.
void	kinematics (bool kine)
	Set whether or not to calculate the kinematics invariants.
void	calculateKinematics (const Lorentz5Momentum &p0, const Lorentz5Momentum &p2, const Lorentz5Momentum &p1)
	Calculate the kinematics for a 3-point vertex.
void	calculateKinematics (const Lorentz5Momentum &p0, const Lorentz5Momentum &p1, const Lorentz5Momentum &p2, const Lorentz5Momentum &p3)
	Calculate the kinematics for a 4-point vertex.
void	calculateKinematics (const vector< Lorentz5Momentum > &p)
	Calculate the kinematics for a n-point vertex.
Energy2	invariant (unsigned int ix, unsigned int iy) const
	Get one of the kinematic invariants.
Static Public Member Functions
static void	Init ()
	Standard Init function used to initialize the interfaces.
Protected Member Functions
void	orderInGem (unsigned int order)
	Set the order in .
void	orderInGs (unsigned int order)
	Set the order in .
Calculation of the strong, electromagnetic and weak couplings
double	strongCoupling (Energy2 q2) const
	Strong coupling.
double	electroMagneticCoupling (Energy2 q2) const
	Electromagnetic coupling.
double	weakCoupling (Energy2 q2) const
	Weak coupling.
double	sin2ThetaW () const
Standard Interfaced functions.
virtual void	doinit ()
	Initialize this object after the setup phase before saving an EventGenerator to disk.
virtual void	rebind (const TranslationMap &trans)
	Rebind pointer to other Interfaced objects.
virtual IVector	getReferences ()
	Return a vector of all pointers to Interfaced objects used in this object.

void	addToList (const vector< long > &ids)
	Members to set-up the particles.
void	addToList (long ida, long idb, long idc, long idd=0)
	Set up the lists of outer particles for the three-/four-point vertex.

void	norm (const Complex &coup)
	Members for the amplitude calculations.
virtual Complex	propagator (int iopt, Energy2 q2, tcPDPtr part, Energy mass=-GeV, Energy width=-GeV)
	Calculate the propagator for a diagram.
Complex	normPropagator (int iopt, Energy2 q2, tcPDPtr part, Energy mass=-GeV, Energy width=-GeV)
	Calculate propagator multiplied by coupling.
Private Member Functions
VertexBase &	operator= (const VertexBase &)
	Private and non-existent assignment operator.
Private Attributes
Complex	_norm
	The overall coupling.
bool	_calckinematics
	Whether or not to calculate the kinematic invariants for the vertex.
vector< vector< Energy2 > >	_kine
	Kinematica quantities needed for loop vertices.
VertexType::T	_theName
	Name of vertex.
unsigned int	_ordergEM
	Order of vertex in .
unsigned int	_ordergS
	Order of vertex in .
unsigned int	_coupopt
	option for the coupling
double	_gs
	Fixed value of strong coupling to use.
double	_ee
	Fixed value of the electromagentic coupling to use.
double	_sw
	Fixed value of $\sin\theta_W$ to use.

vector< vector< PDPtr > >	_particles
	Storage of the particles.
unsigned int	_npoint
	Number of particles at the vertex.
set< tPDPtr >	_inpart
	ParticleData pointers for the allowed incoming particles.
set< tPDPtr >	_outpart
	ParticleData pointers for the allowed outgoing particles.
Static Private Attributes
static AbstractClassDescription < ThePEG::Helicity::VertexBase >	initVertexBase
	Describe a concrete class with persistent data.
Friends
ostream &	operator<< (ostream &, const VertexBase &)
	The output operator is a friend to avoid the data being public.