The MEee2gZ2qq class implements the matrix element for \(e^+e^-\to Z/\gamma \to q\bar{q}\) including spin correlations. More...

#include <MEee2gZ2qq.h>

Inheritance diagram for Herwig::MEee2gZ2qq:

[legend]

Public Member Functions
	MEee2gZ2qq ()
	The default constructor.

virtual POWHEGType	hasPOWHEGCorrection ()
	Members for hard corrections to the emission of QCD radiation.

virtual bool	hasMECorrection ()
	Has an old fashioned ME correction.

virtual void	initializeMECorrection (RealEmissionProcessPtr, double &, double &)
	Initialize the ME correction.

virtual RealEmissionProcessPtr	applyHardMatrixElementCorrection (RealEmissionProcessPtr)
	Apply the hard matrix element correction to a given hard process or decay.

virtual bool	softMatrixElementVeto (PPtr parent, PPtr progenitor, const bool &fs, const Energy &highestpT, const vector< tcPDPtr > &ids, const double &z, const Energy &scale, const Energy &pT)
	Apply the soft matrix element correction.

virtual RealEmissionProcessPtr	generateHardest (RealEmissionProcessPtr, ShowerInteraction)
	Apply the POWHEG style correction.

Virtual functions required by the MEBase class.
virtual unsigned int	orderInAlphaS () const
	Return the order in \(\alpha_S\) in which this matrix element is given.

virtual unsigned int	orderInAlphaEW () const
	Return the order in \(\alpha_{EW}\) in which this matrix element is given.

virtual double	me2 () const
	The matrix element for the kinematical configuration previously provided by the last call to setKinematics(), suitably scaled by sHat() to give a dimension-less number.

virtual Energy2	scale () const
	Return the scale associated with the last set phase space point.

virtual void	getDiagrams () const
	Add all possible diagrams with the add() function.

virtual Selector< DiagramIndex >	diagrams (const DiagramVector &dv) const
	Get diagram selector.

virtual Selector< const ColourLines * >	colourGeometries (tcDiagPtr diag) const
	Return a Selector with possible colour geometries for the selected diagram weighted by their relative probabilities.

virtual void	constructVertex (tSubProPtr)
	Construct the vertex of spin correlations.

Public Member Functions inherited from Herwig::HwMEBase
	HwMEBase ()
	Default constructor.

virtual int	nDim () const
	The number of internal degreed of freedom used in the matrix element.

virtual bool	generateKinematics (const double *r)
	Generate internal degrees of freedom given 'nDim()' uniform random numbers in the interval ]0,1[.

virtual CrossSection	dSigHatDR () const
	Return the matrix element for the kinematical configuation previously provided by the last call to setKinematics().

virtual void	setKinematics ()
	Set the typed and momenta of the incoming and outgoing partons to be used in subsequent calls to me() and colourGeometries() according to the associated XComb object.

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.

Public Member Functions inherited from ThePEG::MEBase
virtual unsigned int	orderInAlphaS () const=0

virtual unsigned int	orderInAlphaEW () const=0

virtual double	me2 () const=0

virtual Energy2	scale () const=0

virtual double	alphaS () const

virtual double	alphaEM () const

void	setKinematics (tPPair in, const PVector &out)

virtual void	setKinematics ()

virtual void	constructVertex (tSubProPtr sub)

virtual void	constructVertex (tSubProPtr sub, const ColourLines *cl)

virtual int	nDim () const

virtual bool	generateKinematics (const double *r)=0

virtual bool	wantCMS () const

virtual bool	headCuts () const

virtual bool	ignoreCuts () const

virtual bool	apply () const

virtual CrossSection	dSigHatDR () const=0

virtual map< string, double >	generateOptionalWeights ()

virtual bool	haveX1X2 () const

virtual bool	havePDFWeight1 () const

virtual bool	havePDFWeight2 () const

virtual bool	keepRandomNumbers () const

virtual void	generateSubCollision (SubProcess &)

virtual void	clearKinematics ()

virtual void	getDiagrams () const=0

virtual bool	noMirror () const

const DiagramVector &	diagrams () const

virtual Selector< const ColourLines * >	colourGeometries (tcDiagPtr diag) const=0

virtual const ColourLines &	selectColourGeometry (tcDiagPtr diag) const

virtual Selector< DiagramIndex >	diagrams (const DiagramVector &) const

virtual DiagramIndex	diagram (const DiagramVector &) const

bool	reweighted () const

double	reWeight () const

double	preWeight () const

void	addReweighter (tReweightPtr rw)

void	addPreweighter (tReweightPtr rw)

Ptr< Amplitude >::pointer	amplitude () const

void	amplitude (Ptr< Amplitude >::pointer amp)

Energy2	sHat () const

double	preweight () const

virtual void	flushCaches ()

virtual StdXCombPtr	makeXComb (Energy newMaxEnergy, const cPDPair &inc, tEHPtr newEventHandler, tSubHdlPtr newSubProcessHandler, tPExtrPtr newExtractor, tCascHdlPtr newCKKW, const PBPair &newPartonBins, tCutsPtr newCuts, const DiagramVector &newDiagrams, bool mir, const PartonPairVec &allPBins, tStdXCombPtr newHead=tStdXCombPtr(), tMEPtr newME=tMEPtr())

virtual StdXCombPtr	makeXComb (tStdXCombPtr newHead, const PBPair &newPartonBins, const DiagramVector &newDiagrams, tMEPtr newME=tMEPtr())

virtual void	fillProjectors ()

virtual void	setXComb (tStdXCombPtr)

const DVector &	meInfo () const

void	meInfo (const DVector &info) const

virtual int	maxMultCKKW () const

virtual int	minMultCKKW () const

virtual void	maxMultCKKW (int mult)

virtual void	minMultCKKW (int mult)

virtual void	setVetoScales (tSubProPtr) const

virtual unsigned int	orderInAlphaS () const=0

virtual unsigned int	orderInAlphaEW () const=0

virtual double	me2 () const=0

virtual Energy2	scale () const=0

virtual double	alphaS () const

virtual double	alphaEM () const

void	setKinematics (tPPair in, const PVector &out)

virtual void	setKinematics ()

virtual void	constructVertex (tSubProPtr sub)

virtual void	constructVertex (tSubProPtr sub, const ColourLines *cl)

virtual int	nDim () const

virtual bool	generateKinematics (const double *r)=0

virtual bool	wantCMS () const

virtual bool	headCuts () const

virtual bool	ignoreCuts () const

virtual bool	apply () const

virtual CrossSection	dSigHatDR () const=0

virtual map< string, double >	generateOptionalWeights ()

virtual bool	haveX1X2 () const

virtual bool	havePDFWeight1 () const

virtual bool	havePDFWeight2 () const

virtual bool	keepRandomNumbers () const

virtual void	generateSubCollision (SubProcess &)

virtual void	clearKinematics ()

virtual void	getDiagrams () const=0

virtual bool	noMirror () const

const DiagramVector &	diagrams () const

virtual Selector< const ColourLines * >	colourGeometries (tcDiagPtr diag) const=0

virtual const ColourLines &	selectColourGeometry (tcDiagPtr diag) const

virtual Selector< DiagramIndex >	diagrams (const DiagramVector &) const

virtual DiagramIndex	diagram (const DiagramVector &) const

bool	reweighted () const

double	reWeight () const

double	preWeight () const

void	addReweighter (tReweightPtr rw)

void	addPreweighter (tReweightPtr rw)

Ptr< Amplitude >::pointer	amplitude () const

void	amplitude (Ptr< Amplitude >::pointer amp)

Energy2	sHat () const

double	preweight () const

virtual void	flushCaches ()

virtual StdXCombPtr	makeXComb (Energy newMaxEnergy, const cPDPair &inc, tEHPtr newEventHandler, tSubHdlPtr newSubProcessHandler, tPExtrPtr newExtractor, tCascHdlPtr newCKKW, const PBPair &newPartonBins, tCutsPtr newCuts, const DiagramVector &newDiagrams, bool mir, const PartonPairVec &allPBins, tStdXCombPtr newHead=tStdXCombPtr(), tMEPtr newME=tMEPtr())

virtual StdXCombPtr	makeXComb (tStdXCombPtr newHead, const PBPair &newPartonBins, const DiagramVector &newDiagrams, tMEPtr newME=tMEPtr())

virtual void	fillProjectors ()

virtual void	setXComb (tStdXCombPtr)

const DVector &	meInfo () const

void	meInfo (const DVector &info) const

virtual int	maxMultCKKW () const

virtual int	minMultCKKW () const

virtual void	maxMultCKKW (int mult)

virtual void	minMultCKKW (int mult)

virtual void	setVetoScales (tSubProPtr) const

void	persistentOutput (PersistentOStream &os) const

void	persistentInput (PersistentIStream &is, int version)

Public Member Functions inherited from ThePEG::HandlerBaseT< UseRandom >
double	rnd () const

double	rnd (double xu) const

double	rnd (double xl, double xu) const

bool	rndbool () const

bool	rndbool (double p) const

bool	rndbool (double p1, double p2) const

int	rndsign (double p1, double p2, double p3) const

int	rnd2 (double p0, double p1) const

int	rnd3 (double p0, double p1, double p2) const

int	rnd4 (double p0, double p1, double p2, double p3) const

long	irnd (long xu=2) const

long	irnd (long xl, long xu) const

const StandardModelBase &	SM () const

tSMPtr	standardModel () const

Public Member Functions inherited from ThePEG::Interfaced
virtual bool	defaultInit ()

PPtr	getParticle (PID) const

PDPtr	getParticleData (PID) const

bool	used () const

void	useMe () const

tEGPtr	generator () const

void	persistentOutput (PersistentOStream &os) const

void	persistentInput (PersistentIStream &is, int version)

PPtr	getParticle (PID) const

PDPtr	getParticleData (PID) const

bool	used () const

void	useMe () const

tEGPtr	generator () const

Public Member Functions inherited from ThePEG::InterfacedBase
string	fullName () const

string	name () const

string	path () const

string	comment () const

void	setup (istream &is)

void	update ()

void	init ()

virtual bool	preInitialize () const

void	initrun ()

void	finish ()

void	touch ()

void	reset ()

void	clear ()

InitState	state () const

bool	locked () const

bool	touched () const

virtual IBPtr	fullclone () const

void	persistentOutput (PersistentOStream &os) const

void	persistentInput (PersistentIStream &is, int version)

virtual void	debugme () const

void	update ()

void	init ()

virtual bool	preInitialize () const

void	initrun ()

void	finish ()

void	touch ()

void	reset ()

void	clear ()

InitState	state () const

bool	locked () const

bool	touched () const

virtual IBPtr	fullclone () const

Public Member Functions inherited from ThePEG::Base
void	debug () const

virtual void	debugme () const

Public Member Functions inherited from ThePEG::Pointer::ReferenceCounted
CounterType	referenceCount () const

Public Member Functions inherited from ThePEG::Named
	Named (const string &newName=string())

	Named (const Named &)=default

const string &	name () const

bool	operator== (const Named &other) const

bool	operator< (const Named &other) const

Public Member Functions inherited from ThePEG::LastXCombInfo< StandardXComb >
const XC &	lastXComb () const

const XC &	lastXComb () const

tXCPtr	lastXCombPtr () const

tXCPtr	lastXCombPtr () const

const XC &	lastHeadXComb () const

const XC &	lastHeadXComb () const

tXCPtr	lastHeadXCombPtr () const

tXCPtr	lastHeadXCombPtr () const

const EventHandler &	lastEventHandler () const

const EventHandler &	lastEventHandler () const

tPExtrPtr	lastExtractor () const

tPExtrPtr	lastExtractor () const

PDFT	pdf (tcPPtr parton) const

PDFT	pdf (tcPPtr parton) const

const Cuts &	lastCuts () const

const Cuts &	lastCuts () const

tCutsPtr	lastCutsPtr () const

tCutsPtr	lastCutsPtr () const

const PPair &	lastParticles () const

const PPair &	lastParticles () const

Energy2	lastS () const

Energy2	lastS () const

const PPair &	lastPartons () const

const PPair &	lastPartons () const

Energy2	lastSHat () const

Energy2	lastSHat () const

double	lastTau () const

double	lastTau () const

double	lastY () const

double	lastY () const

double	lastP1 () const

double	lastP1 () const

double	lastP2 () const

double	lastP2 () const

double	lastL1 () const

double	lastL1 () const

double	lastL2 () const

double	lastL2 () const

double	lastX1 () const

double	lastX1 () const

double	lastX2 () const

double	lastX2 () const

double	lastE1 () const

double	lastE1 () const

double	lastE2 () const

double	lastE2 () const

double	lastFL1L2 () const

double	lastFL1L2 () const

Energy2	lastScale () const

double	lastAlphaS () const

double	lastAlphaEM () const

const vector< Lorentz5Momentum > &	meMomenta () const

double	lastME2 () const

double	lastPreweight () const

double	jacobian () const

CrossSection	lastMECrossSection () const

double	lastMEPDFWeight () const

double	lastMECouplings () const

tSubProPtr	subProcess () const

const cPDVector &	mePartonData () const

Protected Member Functions
Clone Methods.
virtual IBPtr	clone () const
	Make a simple clone of this object.

virtual IBPtr	fullclone () const
	Make a clone of this object, possibly modifying the cloned object to make it sane.

Protected Member Functions inherited from Herwig::HwMEBase
Energy2	tHat () const
	Return the \(\hat{t}\) of the last set phase space point.

Energy2	uHat () const
	Return the \(\hat{u}\) of the last set phase space point.

double	phi () const
	Return the azimuth angle of the last set phase space point.

void	tHat (Energy2 e2)
	Set the \(\hat{t}\) of the last set phase space point.

void	uHat (Energy2 e2)
	Set the \(\hat{u}\) of the last set phase space point.

void	phi (double phi)
	Set the azimuth angle of the last set phase space point.

void	massOption (vector< unsigned int > iopt)
	Set the treatment of the outgoing masses.

void	rescalingOption (unsigned int iopt)
	Rescaled momenta for the helicity ME.

bool	rescaleMomenta (const vector< Lorentz5Momentum > &, const cPDVector &)
	rescale the momenta for the computation of the helicity matrix element

const vector< Lorentz5Momentum > &	rescaledMomenta () const
	Access to the rescaled momenta.

bool	generateMasses (vector< Energy > &masses, double &mjac, const double *r)
	Generate the masses of the particles.

virtual double	getCosTheta (double cthmin, double cthmax, const double r)
	Used internally by generateKinematics, after calculating the limits on cos(theta).

Protected Member Functions inherited from ThePEG::MEBase
virtual void	doinit ()

virtual void	doinitrun ()

void	add (DiagPtr dp) const

vector< Lorentz5Momentum > &	meMomenta ()

void	lastME2 (double v) const

void	lastPreweight (double w) const

void	lastMECrossSection (CrossSection v) const

void	lastMEPDFWeight (double v) const

void	lastMECouplings (double v) const

void	jacobian (double j)

void	use (tcMEPtr other)

void	useDiagrams (tcMEPtr other) const

Protected Member Functions inherited from ThePEG::Interfaced
void	reporeg (IBPtr object, string name) const

bool	setDefaultReference (PtrT &ptr, string classname, string objectname)

	Interfaced (const string &newName)

	Interfaced (const Interfaced &i)

void	setGenerator (tEGPtr generator)

Protected Member Functions inherited from ThePEG::InterfacedBase
virtual void	readSetup (istream &is)

virtual void	doupdate ()

virtual void	doinit ()

virtual void	doinitrun ()

virtual void	dofinish ()

virtual IVector	getReferences ()

virtual void	rebind (const TranslationMap &)

virtual IBPtr	clone () const=0

	InterfacedBase (string newName)

	InterfacedBase (const InterfacedBase &i)

virtual void	readSetup (istream &is)

virtual void	doupdate ()

virtual void	doinit ()

virtual void	doinitrun ()

virtual void	dofinish ()

virtual IVector	getReferences ()

virtual void	rebind (const TranslationMap &)

Protected Member Functions inherited from ThePEG::Pointer::ReferenceCounted
	ReferenceCounted (const ReferenceCounted &)

ReferenceCounted &	operator= (const ReferenceCounted &)

Protected Member Functions inherited from ThePEG::Named
const Named &	operator= (const Named &other)

const string &	name (const string &newName)

Standard Interfaced functions.
int	minflav_
	Parameters controlling the leading-order process.

int	maxflav_
	The maximum PDG of the quarks to be produced.

unsigned int	massopt_
	Option for the treatment of the top quark mass.

AbstractFFVVertexPtr	FFZVertex_
	Pointers to the vertices.

AbstractFFVVertexPtr	FFPVertex_
	Pointer to the fermion-antifermion photon vertex.

AbstractFFVVertexPtr	FFGVertex_
	Pointer to the fermion-antifermion photon vertex.

bool	spinCorrelations_
	Switch on/off the helivity vertex construction.

PDPtr	Z0_
	Pointer to the ParticleData objects.

PDPtr	gamma_
	Pointer to the particle data object for the photon.

PDPtr	gluon_
	Pointer to the particle data object for the gluon.

Energy	d_Q_
	CM energy.

Energy	d_m_
	Quark mass.

double	d_rho_
	The rho parameter.

double	d_v_
	The v parameter.

double	d_kt1_
	The initial kappa-tilde values for radiation from the quark.

double	d_kt2_
	The initial kappa-tilde values for radiation from the antiquark.

ShowerAlphaPtr	alphaQCD_
	Pointer to the strong coupling.

ShowerAlphaPtr	alphaQED_
	Pointer to the EM coupling.

Energy	pTminQED_
	Variables for the POWHEG style corrections.

Energy	pTminQCD_
	The cut off on pt for QCD, assuming massless quarks.

double	preFactor_
	Overestimate for the prefactor.

vector< cPDPtr >	partons_
	ParticleData objects for the partons.

vector< Lorentz5Momentum >	loMomenta_
	Momenta of the leading-order partons.

static const double	EPS_
	Cut-off parameter.

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.

double	loME (const vector< cPDPtr > &partons, const vector< Lorentz5Momentum > &momenta, bool first) const
	Calculate the matrix element for \(e^+e^-\to q \bar{q}\).

ProductionMatrixElement	HelicityME (vector< SpinorWaveFunction > &fin, vector< SpinorBarWaveFunction > &ain, vector< SpinorBarWaveFunction > &fout, vector< SpinorWaveFunction > &aout, double &me, double &cont, double &BW) const
	Member to calculate the matrix element.

double	meRatio (vector< cPDPtr > partons, vector< Lorentz5Momentum > momenta, unsigned int iemitter, ShowerInteraction inter, bool subtract=false) const
	The ratio of the matrix element for one additional jet over the leading order result.

InvEnergy2	realME (const vector< cPDPtr > &partons, const vector< Lorentz5Momentum > &momenta, ShowerInteraction inter) const
	Calculate the matrix element for \(e^-e^-\to q \bar q g\).

AbstractFFVVertexPtr	FFZVertex () const
	Pointer to the fermion-antifermion Z vertex.

AbstractFFVVertexPtr	FFPVertex () const
	Pointer to the fermion-antifermion photon vertex.

PDPtr	Z0 () const
	Pointer to the particle data object for the Z.

PDPtr	gamma () const
	Pointer to the particle data object for the photon.

PDPtr	gluon () const
	Pointer to the particle data object for the gluon.

pair< Energy, ShowerInteraction >	generateHard (RealEmissionProcessPtr, vector< Lorentz5Momentum > &emission, unsigned int &iemit, unsigned int &ispect, bool applyVeto, ShowerInteraction)
	Generate the momenta for a hard configuration.

RealEmissionProcessPtr	calculateRealEmission (RealEmissionProcessPtr born, bool veto, ShowerInteraction inter)
	Calculate the reall emission.

double	getKfromX (double, double)
	Calculate \(\tilde{\kappa}\).

double	MEV (double, double)
	Vector and axial vector parts of the matrix element.

double	PS (double x1, double x2)
	The matrix element, given \(x_1\), \(x_2\).

MEee2gZ2qq &	operator= (const MEee2gZ2qq &)=delete
	The assignment operator is private and must never be called.

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 void	Init ()
	The standard Init function used to initialize the interfaces.

Additional Inherited Members
Public Types inherited from Herwig::HwMEBase
enum	POWHEGType { No , ISR , FSR , Both }
	Virtual members to be overridden by inheriting classes which implement hard corrections. More...

Public Types inherited from ThePEG::MEBase
typedef vector< DiagPtr >	DiagramVector

typedef DiagramVector::size_type	DiagramIndex

typedef vector< ReweightPtr >	ReweightVector

Public Types inherited from ThePEG::InterfacedBase
enum	InitState

Public Types inherited from ThePEG::Pointer::ReferenceCounted
typedef unsigned int	CounterType

Public Types inherited from ThePEG::LastXCombInfo< StandardXComb >
typedef ThePEG::Ptr< XC >::pointer	XCPtr

typedef ThePEG::Ptr< XC >::const_pointer	cXCPtr

typedef ThePEG::Ptr< XC >::transient_pointer	tXCPtr

typedef ThePEG::Ptr< XC >::transient_const_pointer	tcXCPtr

Static Public Member Functions inherited from Herwig::HwMEBase
static void	Init ()
	The standard Init function used to initialize the interfaces.

Static Public Member Functions inherited from ThePEG::MEBase
static void	Init ()

Static Public Member Functions inherited from ThePEG::HandlerBase
static void	Init ()

Static Public Member Functions inherited from ThePEG::Interfaced
static void	Init ()

Static Public Member Functions inherited from ThePEG::InterfacedBase
static void	Init ()

Static Public Member Functions inherited from ThePEG::Base
static void	Init ()

Public Attributes inherited from ThePEG::InterfacedBase
	initializing

	uninitialized

	initialized

	runready

Public Attributes inherited from ThePEG::Pointer::ReferenceCounted
const unsigned long	uniqueId

Static Protected Member Functions inherited from ThePEG::Interfaced
static void	registerRepository (IBPtr)

static void	registerRepository (IBPtr, string newName)

Protected Attributes inherited from ThePEG::LastXCombInfo< StandardXComb >
XCPtr	theLastXComb

Detailed Description

The MEee2gZ2qq class implements the matrix element for \(e^+e^-\to Z/\gamma \to q\bar{q}\) including spin correlations.

The class includes greater control over the type of quark produced than is available in the corresponding matrix element from ThePEG, in addition to spin correlations.

See also: The interfaces defined for MEee2gZ2qq.

Definition at line 38 of file MEee2gZ2qq.h.

Constructor & Destructor Documentation

◆ MEee2gZ2qq()

Herwig::MEee2gZ2qq::MEee2gZ2qq ( )

inline

The default constructor.

Definition at line 45 of file MEee2gZ2qq.h.

References massopt_, maxflav_, minflav_, preFactor_, pTminQCD_, pTminQED_, and spinCorrelations_.

Member Function Documentation

◆ applyHardMatrixElementCorrection()

virtual RealEmissionProcessPtr Herwig::MEee2gZ2qq::applyHardMatrixElementCorrection ( RealEmissionProcessPtr )

virtual

Apply the hard matrix element correction to a given hard process or decay.

Reimplemented from Herwig::HwMEBase.

◆ clone()

virtual IBPtr Herwig::MEee2gZ2qq::clone ( ) const

inlineprotectedvirtual

Make a simple clone of this object.

Returns: a pointer to the new object.

Implements ThePEG::InterfacedBase.

Definition at line 197 of file MEee2gZ2qq.h.

◆ colourGeometries()

virtual Selector< const ColourLines * > Herwig::MEee2gZ2qq::colourGeometries ( tcDiagPtr diag ) const

virtual

Return a Selector with possible colour geometries for the selected diagram weighted by their relative probabilities.

Parameters

diag	the diagram chosen.

Returns: the possible colour geometries weighted by their relative probabilities.

Implements ThePEG::MEBase.

◆ constructVertex()

virtual void Herwig::MEee2gZ2qq::constructVertex ( tSubProPtr )

virtual

Construct the vertex of spin correlations.

Reimplemented from ThePEG::MEBase.

◆ diagrams()

virtual Selector< DiagramIndex > Herwig::MEee2gZ2qq::diagrams ( const DiagramVector & dv ) const

virtual

Get diagram selector.

With the information previously supplied with the setKinematics method, a derived class may optionally override this method to weight the given diagrams with their (although certainly not physical) relative probabilities.

Parameters

dv	the diagrams to be weighted.

Returns: a Selector relating the given diagrams to their weights.

Reimplemented from ThePEG::MEBase.

◆ doinit()

virtual void Herwig::MEee2gZ2qq::doinit ( )

protectedvirtual

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::MEBase.

◆ FFPVertex()

AbstractFFVVertexPtr Herwig::MEee2gZ2qq::FFPVertex ( ) const

inlineprotected

Pointer to the fermion-antifermion photon vertex.

Definition at line 344 of file MEee2gZ2qq.h.

References FFPVertex_.

◆ FFZVertex()

AbstractFFVVertexPtr Herwig::MEee2gZ2qq::FFZVertex ( ) const

inlineprotected

Pointer to the fermion-antifermion Z vertex.

Definition at line 339 of file MEee2gZ2qq.h.

References FFZVertex_.

◆ fullclone()

virtual IBPtr Herwig::MEee2gZ2qq::fullclone ( ) const

inlineprotectedvirtual

Make a clone of this object, possibly modifying the cloned object to make it sane.

Returns: a pointer to the new object.

Reimplemented from ThePEG::InterfacedBase.

Definition at line 203 of file MEee2gZ2qq.h.

◆ gamma()

PDPtr Herwig::MEee2gZ2qq::gamma ( ) const

inlineprotected

Pointer to the particle data object for the photon.

Definition at line 354 of file MEee2gZ2qq.h.

References gamma_.

◆ generateHardest()

virtual RealEmissionProcessPtr Herwig::MEee2gZ2qq::generateHardest	(	RealEmissionProcessPtr	,
		ShowerInteraction
	)

virtual

Apply the POWHEG style correction.

Reimplemented from Herwig::HwMEBase.

◆ getDiagrams()

virtual void Herwig::MEee2gZ2qq::getDiagrams ( ) const

virtual

Add all possible diagrams with the add() function.

Implements ThePEG::MEBase.

◆ getReferences()

virtual IVector Herwig::MEee2gZ2qq::getReferences ( )

protectedvirtual

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

Returns: a vector of pointers.

Reimplemented from ThePEG::InterfacedBase.

◆ gluon()

PDPtr Herwig::MEee2gZ2qq::gluon ( ) const

inlineprotected

Pointer to the particle data object for the gluon.

Definition at line 359 of file MEee2gZ2qq.h.

References gluon_.

◆ hasMECorrection()

virtual bool Herwig::MEee2gZ2qq::hasMECorrection ( )

inlinevirtual

Has an old fashioned ME correction.

Reimplemented from Herwig::HwMEBase.

Definition at line 63 of file MEee2gZ2qq.h.

◆ hasPOWHEGCorrection()

virtual POWHEGType Herwig::MEee2gZ2qq::hasPOWHEGCorrection ( )

inlinevirtual

Members for hard corrections to the emission of QCD radiation.

Has a POWHEG style correction

Reimplemented from Herwig::HwMEBase.

Definition at line 58 of file MEee2gZ2qq.h.

◆ HelicityME()

ProductionMatrixElement Herwig::MEee2gZ2qq::HelicityME	(	vector< SpinorWaveFunction > &	fin,
		vector< SpinorBarWaveFunction > &	ain,
		vector< SpinorBarWaveFunction > &	fout,
		vector< SpinorWaveFunction > &	aout,
		double &	me,
		double &	cont,
		double &	BW
	)		const

protected

Member to calculate the matrix element.

Parameters

fin	Spinors for incoming fermion
ain	Spinors for incoming antifermion
fout	Spinors for outgoing fermion
aout	Spinors for outgong antifermion
me	Spin summed Matrix element
cont	The continuum piece of the matrix element
BW	The Z piece of the matrix element

◆ Init()

static void Herwig::MEee2gZ2qq::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.

◆ initializeMECorrection()

virtual void Herwig::MEee2gZ2qq::initializeMECorrection	(	RealEmissionProcessPtr	,
		double &	,
		double &
	)

virtual

Initialize the ME correction.

Reimplemented from Herwig::HwMEBase.

◆ loME()

double Herwig::MEee2gZ2qq::loME	(	const vector< cPDPtr > &	partons,
		const vector< Lorentz5Momentum > &	momenta,
		bool	first
	)		const

protected

Calculate the matrix element for \(e^+e^-\to q \bar{q}\).

Parameters

partons	The incoming and outgoing particles
momenta	The momenta of the incoming and outgoing particles
first	Whether or not to calculate the spin correlations

◆ me2()

virtual double Herwig::MEee2gZ2qq::me2 ( ) const

virtual

The matrix element for the kinematical configuration previously provided by the last call to setKinematics(), suitably scaled by sHat() to give a dimension-less number.

Returns: the matrix element scaled with sHat() to give a dimensionless number.

Implements ThePEG::MEBase.

◆ meRatio()

double Herwig::MEee2gZ2qq::meRatio	(	vector< cPDPtr >	partons,
		vector< Lorentz5Momentum >	momenta,
		unsigned int	iemitter,
		ShowerInteraction	inter,
		bool	subtract = `false`
	)		const

protected

The ratio of the matrix element for one additional jet over the leading order result.

In practice

\[\frac{\hat{s}|\overline{\mathcal{M}}|^2_2|D_{\rm emit}|}{4\pi C_F\alpha_S|\overline{\mathcal{M}}|^2_3\left(|D_{\rm emit}|+|D_{\rm spect}|\right)}\]

is returned where \(\|\overline{\mathcal{M}}|^2\) is the spin and colour summed/averaged matrix element.

Parameters

partons	The incoming and outgoing particles
momenta	The momenta of the incoming and outgoing particles
iemitter	Whether the quark or antiquark is regardede as the emitter
inter	The type of interaction
subtract	Whether or not to subtract the relevant dipole term

◆ MEV()

double Herwig::MEee2gZ2qq::MEV	(	double	,
		double
	)

private

Vector and axial vector parts of the matrix element.

Vector part of the matrix element

◆ operator=()

MEee2gZ2qq & Herwig::MEee2gZ2qq::operator= ( const MEee2gZ2qq & )

privatedelete

The assignment operator is private and must never be called.

In fact, it should not even be implemented.

◆ orderInAlphaEW()

virtual unsigned int Herwig::MEee2gZ2qq::orderInAlphaEW ( ) const

virtual

Return the order in \(\alpha_{EW}\) in which this matrix element is given.

Implements ThePEG::MEBase.

◆ orderInAlphaS()

virtual unsigned int Herwig::MEee2gZ2qq::orderInAlphaS ( ) const

virtual

Return the order in \(\alpha_S\) in which this matrix element is given.

Implements ThePEG::MEBase.

◆ persistentInput()

void Herwig::MEee2gZ2qq::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.

◆ persistentOutput()

void Herwig::MEee2gZ2qq::persistentOutput ( PersistentOStream & os ) const

Function used to write out object persistently.

Parameters

os	the persistent output stream written to.

◆ PS()

double Herwig::MEee2gZ2qq::PS	(	double	x1,
		double	x2
	)

private

The matrix element, given \(x_1\), \(x_2\).

Parameters

x1	\(x_1\)
x2	\(x_2\)

◆ realME()

InvEnergy2 Herwig::MEee2gZ2qq::realME	(	const vector< cPDPtr > &	partons,
		const vector< Lorentz5Momentum > &	momenta,
		ShowerInteraction	inter
	)		const

protected

Calculate the matrix element for \(e^-e^-\to q \bar q g\).

Parameters

partons	The incoming and outgoing particles
momenta	The momenta of the incoming and outgoing particles
inter	The type of interaction

◆ rebind()

virtual void Herwig::MEee2gZ2qq::rebind ( const TranslationMap & trans )

protectedvirtual

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.

◆ scale()

virtual Energy2 Herwig::MEee2gZ2qq::scale ( ) const

virtual

Return the scale associated with the last set phase space point.

Implements ThePEG::MEBase.

◆ softMatrixElementVeto()

virtual bool Herwig::MEee2gZ2qq::softMatrixElementVeto	(	PPtr	parent,
		PPtr	progenitor,
		const bool &	fs,
		const Energy &	highestpT,
		const vector< tcPDPtr > &	ids,
		const double &	z,
		const Energy &	scale,
		const Energy &	pT
	)

virtual

Apply the soft matrix element correction.

Parameters

parent	The initial particle in the current branching
progenitor	The progenitor particle of the jet
fs	Whether the emission is initial or final-state
highestpT	The highest pT so far in the shower
ids	ids of the particles produced in the branching
z	The momentum fraction of the branching
scale	the evolution scale of the branching
pT	The transverse momentum of the branching

Returns: If true the emission should be vetoed

Reimplemented from Herwig::HwMEBase.

◆ Z0()

PDPtr Herwig::MEee2gZ2qq::Z0 ( ) const

inlineprotected

Pointer to the particle data object for the Z.

Definition at line 349 of file MEee2gZ2qq.h.

References Z0_.

Member Data Documentation

◆ alphaQCD_

ShowerAlphaPtr Herwig::MEee2gZ2qq::alphaQCD_

private

Pointer to the strong coupling.

Definition at line 474 of file MEee2gZ2qq.h.

◆ alphaQED_

ShowerAlphaPtr Herwig::MEee2gZ2qq::alphaQED_

private

Pointer to the EM coupling.

Definition at line 479 of file MEee2gZ2qq.h.

◆ d_kt1_

double Herwig::MEee2gZ2qq::d_kt1_

private

The initial kappa-tilde values for radiation from the quark.

Definition at line 459 of file MEee2gZ2qq.h.

◆ d_kt2_

double Herwig::MEee2gZ2qq::d_kt2_

private

The initial kappa-tilde values for radiation from the antiquark.

Definition at line 464 of file MEee2gZ2qq.h.

◆ d_m_

Energy Herwig::MEee2gZ2qq::d_m_

private

Quark mass.

Definition at line 444 of file MEee2gZ2qq.h.

◆ d_Q_

Energy Herwig::MEee2gZ2qq::d_Q_

private

CM energy.

Definition at line 439 of file MEee2gZ2qq.h.

◆ d_rho_

double Herwig::MEee2gZ2qq::d_rho_

private

The rho parameter.

Definition at line 449 of file MEee2gZ2qq.h.

◆ d_v_

double Herwig::MEee2gZ2qq::d_v_

private

The v parameter.

Definition at line 454 of file MEee2gZ2qq.h.

◆ EPS_

const double Herwig::MEee2gZ2qq::EPS_

staticprivate

Cut-off parameter.

Definition at line 469 of file MEee2gZ2qq.h.

◆ FFGVertex_

AbstractFFVVertexPtr Herwig::MEee2gZ2qq::FFGVertex_

private

Pointer to the fermion-antifermion photon vertex.

Definition at line 408 of file MEee2gZ2qq.h.

◆ FFPVertex_

AbstractFFVVertexPtr Herwig::MEee2gZ2qq::FFPVertex_

private

Pointer to the fermion-antifermion photon vertex.

Definition at line 403 of file MEee2gZ2qq.h.

Referenced by FFPVertex().

◆ FFZVertex_

AbstractFFVVertexPtr Herwig::MEee2gZ2qq::FFZVertex_

private

Pointers to the vertices.

Pointer to the fermion-antifermion Z vertex

Definition at line 398 of file MEee2gZ2qq.h.

Referenced by FFZVertex().

◆ gamma_

PDPtr Herwig::MEee2gZ2qq::gamma_

private

Pointer to the particle data object for the photon.

Definition at line 428 of file MEee2gZ2qq.h.

Referenced by gamma().

◆ gluon_

PDPtr Herwig::MEee2gZ2qq::gluon_

private

Pointer to the particle data object for the gluon.

Definition at line 433 of file MEee2gZ2qq.h.

Referenced by gluon().

◆ loMomenta_

vector<Lorentz5Momentum> Herwig::MEee2gZ2qq::loMomenta_

private

Momenta of the leading-order partons.

Definition at line 509 of file MEee2gZ2qq.h.

◆ massopt_

unsigned int Herwig::MEee2gZ2qq::massopt_

private

Option for the treatment of the top quark mass.

Definition at line 388 of file MEee2gZ2qq.h.

Referenced by MEee2gZ2qq().

◆ maxflav_

int Herwig::MEee2gZ2qq::maxflav_

private

The maximum PDG of the quarks to be produced.

Definition at line 383 of file MEee2gZ2qq.h.

Referenced by MEee2gZ2qq().

◆ minflav_

int Herwig::MEee2gZ2qq::minflav_

private

Parameters controlling the leading-order process.

The minimum PDG of the quarks to be produced

Definition at line 378 of file MEee2gZ2qq.h.

Referenced by MEee2gZ2qq().

◆ partons_

vector<cPDPtr> Herwig::MEee2gZ2qq::partons_

private

ParticleData objects for the partons.

Definition at line 504 of file MEee2gZ2qq.h.

◆ preFactor_

double Herwig::MEee2gZ2qq::preFactor_

private

Overestimate for the prefactor.

Definition at line 499 of file MEee2gZ2qq.h.

Referenced by MEee2gZ2qq().

◆ pTminQCD_

Energy Herwig::MEee2gZ2qq::pTminQCD_

private

The cut off on pt for QCD, assuming massless quarks.

Definition at line 494 of file MEee2gZ2qq.h.

Referenced by MEee2gZ2qq().

◆ pTminQED_

Energy Herwig::MEee2gZ2qq::pTminQED_

private

Variables for the POWHEG style corrections.

The cut off on pt for QED, assuming massless quarks.

Definition at line 490 of file MEee2gZ2qq.h.

Referenced by MEee2gZ2qq().

◆ spinCorrelations_

bool Herwig::MEee2gZ2qq::spinCorrelations_

private

Switch on/off the helivity vertex construction.

Definition at line 414 of file MEee2gZ2qq.h.

Referenced by MEee2gZ2qq().

◆ Z0_

PDPtr Herwig::MEee2gZ2qq::Z0_

private

Pointer to the ParticleData objects.

Pointer to the particle data object for the Z

Definition at line 423 of file MEee2gZ2qq.h.

Referenced by Z0().

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

MEee2gZ2qq.h

Public Member Functions

Protected Member Functions

Standard Interfaced functions.

Functions used by the persistent I/O system.

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ MEee2gZ2qq()

Member Function Documentation

◆ applyHardMatrixElementCorrection()

◆ clone()

◆ colourGeometries()

◆ constructVertex()

◆ diagrams()

◆ doinit()

◆ FFPVertex()

◆ FFZVertex()

◆ fullclone()

◆ gamma()

◆ generateHardest()

◆ getDiagrams()

◆ getReferences()

◆ gluon()

◆ hasMECorrection()

◆ hasPOWHEGCorrection()

◆ HelicityME()

◆ Init()

◆ initializeMECorrection()

◆ loME()

◆ me2()

◆ meRatio()

◆ MEV()

◆ operator=()

◆ orderInAlphaEW()

◆ orderInAlphaS()

◆ persistentInput()

◆ persistentOutput()

◆ PS()

◆ realME()

◆ rebind()

◆ scale()

◆ softMatrixElementVeto()

◆ Z0()

Member Data Documentation

◆ alphaQCD_

◆ alphaQED_

◆ d_kt1_

◆ d_kt2_

◆ d_m_

◆ d_Q_

◆ d_rho_

◆ d_v_

◆ EPS_

◆ FFGVertex_

◆ FFPVertex_

◆ FFZVertex_

◆ gamma_

◆ gluon_

◆ loMomenta_

◆ massopt_

◆ maxflav_

◆ minflav_

◆ partons_

◆ preFactor_

◆ pTminQCD_

◆ pTminQED_

◆ spinCorrelations_

◆ Z0_