Herwig::WeakDecayCurrent Class Reference

The WeakDecayCurrent class is the base class for the hadronic currents produced in weak decays. More...

#include <WeakDecayCurrent.h>

Inheritance diagram for Herwig::WeakDecayCurrent:

List of all members.

Public Member Functions
	WeakDecayCurrent ()
	Default constructor.
unsigned int	numberOfModes () const
	Return the number of modes handled by this current.
virtual vector < LorentzPolarizationVectorE >	current (const int imode, const int ichan, Energy &scale, const ParticleVector &decay, DecayIntegrator::MEOption meopt) const =0
	Hadronic current.
virtual bool	accept (vector< int > id)=0
	Accept the decay.
virtual unsigned int	decayMode (vector< int > id)=0
	Return the decay mode number for a given set of particles in the current.
void	decayModeInfo (unsigned int imode, int &iq, int &ia) const
	Information on a decay mode.
virtual void	dataBaseOutput (ofstream &os, bool header, bool create) const
	Output the setup information for the particle database.
Methods for the construction of the phase space integrator.
virtual bool	createMode (int icharge, unsigned int imode, DecayPhaseSpaceModePtr mode, unsigned int iloc, unsigned int ires, DecayPhaseSpaceChannelPtr phase, Energy upp)=0
	Complete the construction of the decay mode for integration.classes inheriting from this one.
virtual tPDVector	particles (int icharge, unsigned int imode, int iq, int ia)=0
	The particles produced by the current.
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.
Static Public Member Functions
static void	Init ()
	Standard Init function used to initialize the interfaces.
Protected Member Functions
void	addDecayMode (int iq, int ia)
	Add a decay mode to the list.
void	setInitialModes (unsigned int nmodes)
	Set initial number of modes.
Private Member Functions
WeakDecayCurrent &	operator= (const WeakDecayCurrent &)
	Private and non-existent assignment operator.
Private Attributes
vector< int >	_quark
	The PDG codes for the quarks contained in the current.
vector< int >	_antiquark
	The PDG codes for the antiquarks contained in the current.
unsigned int	_numbermodes
	The initial number of modes.
Static Private Attributes
static AbstractClassDescription < WeakDecayCurrent >	initWeakDecayCurrent
	Describe an abstract base class with persistent data.

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Detailed Description

The WeakDecayCurrent class is the base class for the hadronic currents produced in weak decays.

This is designed so it can be used in any weak decay. In general the currents which are implemented are either simple one meson production or taken from tau decay.

In classes inheriting from this one a number of member functions must be implemented

• createMode which takes a vector of partially completed DecayPhaseSpaceChannel and adds the extra information required for the current. This method should assume that the particles from the current are the last ones specified in the DecayPhaseSpaceMode. This method will then construct the DecayPhaseSpaceMode for the decay.

• particles() which returns the external particles produced by the current.

• current() which given the decay products calculates the decay current

• accept() which uses the PDG codes for the particles in the current to decide if a given mode is allowed.

• decayMode() which uses the PDG codes for the particles in the current to workout which modes is being performed.

• dataBaseOutput() which should output the information on all the Interfaces so that the WeakDecayCurrent can be reconstructed by the Herwig++ particle properties database.

See also:

Interfaced.

Definition at line 57 of file WeakDecayCurrent.h.

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Member Function Documentation

virtual bool Herwig::WeakDecayCurrent::accept

(

vector< int >

id

)

[pure virtual]

Accept the decay.

This method is purely virtual and must be implemented in any class inheriting from this one.

Parameters:

id	The id's of the particles in the current.

Returns:

Can this current have the external particles specified.

Implemented in Herwig::TwoPionPhotonCurrent, Herwig::FourPionNovosibirskCurrent, Herwig::ScalarMesonCurrent, Herwig::VectorMesonCurrent, Herwig::TwoMesonRhoKStarCurrent, Herwig::LeptonNeutrinoCurrent, Herwig::ThreeMesonCurrentBase, Herwig::KPiCurrent, and Herwig::FivePionCurrent.

void Herwig::WeakDecayCurrent::addDecayMode	(	int	iq,
		int	ia
	)		[inline, protected]

Add a decay mode to the list.

Parameters:

iq	The PDG code for the quark.
ia	The PDG code for the antiquark.

Definition at line 193 of file WeakDecayCurrent.h.

virtual bool Herwig::WeakDecayCurrent::createMode	(	int	icharge,
		unsigned int	imode,
		DecayPhaseSpaceModePtr	mode,
		unsigned int	iloc,
		unsigned int	ires,
		DecayPhaseSpaceChannelPtr	phase,
		Energy	upp
	)		[pure virtual]

Complete the construction of the decay mode for integration.classes inheriting from this one.

This method is purely virtual and must be implemented in the classes inheriting from WeakDecayCurrent.

Parameters:

icharge	The total charge of the outgoing particles in the current.
imode	The mode in the current being asked for.
mode	The phase space mode for the integration
iloc	The location of the of the first particle from the current in the list of outgoing particles.
ires	The location of the first intermediate for the current.
phase	The prototype phase space channel for the integration.
upp	The maximum possible mass the particles in the current are allowed to have.

Returns:

Whether the current was sucessfully constructed.

Implemented in Herwig::ThreePionCLEOCurrent, Herwig::TwoPionPhotonCurrent, Herwig::ThreeMesonDefaultCurrent, Herwig::FourPionNovosibirskCurrent, Herwig::ScalarMesonCurrent, Herwig::VectorMesonCurrent, Herwig::TwoMesonRhoKStarCurrent, Herwig::LeptonNeutrinoCurrent, Herwig::KaonThreeMesonCurrent, Herwig::KPiCurrent, and Herwig::FivePionCurrent.

virtual vector<LorentzPolarizationVectorE> Herwig::WeakDecayCurrent::current	(	const int	imode,
		const int	ichan,
		Energy &	scale,
		const ParticleVector &	decay,
		DecayIntegrator::MEOption	meopt
	)		const [pure virtual]

Hadronic current.

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

Parameters:

imode	The mode
ichan	The phase-space channel the current is needed for.
scale	The invariant mass of the particles in the current.
decay	The decay products
meopt	Option for the calculation of the matrix element

Returns:

The current.

Implemented in Herwig::TwoPionPhotonCurrent, Herwig::FourPionNovosibirskCurrent, Herwig::ScalarMesonCurrent, Herwig::VectorMesonCurrent, Herwig::TwoMesonRhoKStarCurrent, Herwig::LeptonNeutrinoCurrent, Herwig::ThreeMesonCurrentBase, Herwig::KPiCurrent, and Herwig::FivePionCurrent.

virtual void Herwig::WeakDecayCurrent::dataBaseOutput	(	ofstream &	os,
		bool	header,
		bool	create
	)		const [virtual]

Output the setup information for the particle database.

Parameters:

os	The stream to output the information to
header	Whether or not to output the information for MySQL
create	Whether or not to add a statement creating the object

Reimplemented in Herwig::ThreePionCLEOCurrent, Herwig::TwoPionPhotonCurrent, Herwig::FourPionNovosibirskCurrent, Herwig::ScalarMesonCurrent, Herwig::VectorMesonCurrent, Herwig::TwoMesonRhoKStarCurrent, Herwig::ThreeMesonCurrentBase, Herwig::LeptonNeutrinoCurrent, Herwig::ThreeMesonDefaultCurrent, Herwig::KPiCurrent, Herwig::FivePionCurrent, and Herwig::KaonThreeMesonCurrent.

virtual unsigned int Herwig::WeakDecayCurrent::decayMode

(

vector< int >

id

)

[pure virtual]

Return the decay mode number for a given set of particles in the current.

This method is purely virtual and must be implemented in any class inheriting from this one.

Parameters:

id	The id's of the particles in the current.

Returns:

The number of the mode

Implemented in Herwig::TwoPionPhotonCurrent, Herwig::FourPionNovosibirskCurrent, Herwig::ScalarMesonCurrent, Herwig::VectorMesonCurrent, Herwig::TwoMesonRhoKStarCurrent, Herwig::LeptonNeutrinoCurrent, Herwig::ThreeMesonCurrentBase, Herwig::KPiCurrent, and Herwig::FivePionCurrent.

void Herwig::WeakDecayCurrent::decayModeInfo	(	unsigned int	imode,
		int &	iq,
		int &	ia
	)		const [inline]

Information on a decay mode.

Parameters:

imode	The mode
iq	The PDG code of the quark.
ia	The PDG code of the antiquark.

Definition at line 144 of file WeakDecayCurrent.h.

virtual tPDVector Herwig::WeakDecayCurrent::particles	(	int	icharge,
		unsigned int	imode,
		int	iq,
		int	ia
	)		[pure virtual]

The particles produced by the current.

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

Parameters:

icharge	The total charge of the particles in the current.
imode	The mode for which the particles are being requested
iq	The PDG code for the quark
ia	The PDG code for the antiquark

Returns:

The external particles for the current.

Implemented in Herwig::TwoPionPhotonCurrent, Herwig::ThreeMesonCurrentBase, Herwig::FourPionNovosibirskCurrent, Herwig::ScalarMesonCurrent, Herwig::VectorMesonCurrent, Herwig::TwoMesonRhoKStarCurrent, Herwig::LeptonNeutrinoCurrent, Herwig::KPiCurrent, and Herwig::FivePionCurrent.

void Herwig::WeakDecayCurrent::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.

Reimplemented in Herwig::TwoMesonRhoKStarCurrent, Herwig::ThreePionCLEOCurrent, Herwig::KaonThreeMesonCurrent, Herwig::KPiCurrent, Herwig::FivePionCurrent, Herwig::TwoPionPhotonCurrent, Herwig::ThreeMesonDefaultCurrent, Herwig::FourPionNovosibirskCurrent, Herwig::ScalarMesonCurrent, and Herwig::VectorMesonCurrent.

void Herwig::WeakDecayCurrent::persistentOutput

(

PersistentOStream &

os

)

const

Function used to write out object persistently.

Parameters:

os	the persistent output stream written to.

Reimplemented from ThePEG::Interfaced.

Reimplemented in Herwig::TwoMesonRhoKStarCurrent, Herwig::ThreePionCLEOCurrent, Herwig::KaonThreeMesonCurrent, Herwig::KPiCurrent, Herwig::FivePionCurrent, Herwig::TwoPionPhotonCurrent, Herwig::ThreeMesonDefaultCurrent, Herwig::FourPionNovosibirskCurrent, Herwig::ScalarMesonCurrent, and Herwig::VectorMesonCurrent.

void Herwig::WeakDecayCurrent::setInitialModes

(

unsigned int

nmodes

)

[inline, protected]

Set initial number of modes.

Parameters:

nmodes

The number of modes.

Definition at line 202 of file WeakDecayCurrent.h.

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

• WeakDecayCurrent.h