A ColourSinglet object represents a set of colour-connected partons in a total colour-singlet state. More...

#include <ColourSinglet.h>

Public Types
typedef deque< tcPPtr >	StringPiece
	A piece of string. More...

typedef StringPiece::size_type	Index
	An integer type used as index in a string pieece. More...

typedef pair< Index, Index >	Junction
	Representaion of a junction. More...

Public Member Functions
	ColourSinglet ()
	Default constructor.

	ColourSinglet (tcColinePtr cl, tcParticleSet &left)
	Constructor taking an initial colour line and a set of partons to select from.

tcPVector &	partons ()
	Access the vector of partons.

const tcPVector &	partons () const
	Access the vector of partons.

tcPPtr	parton (tcPVector::size_type i) const
	Access a parton giving an index.

LorentzMomentum	momentum () const
	Return the total momentum for the partons in the colour singlet.

Index	nPieces () const
	Return the number of string pieces.

StringPiece &	piece (Index i)
	Return the partons belonging to string piece with index i (note that the indices starts with 1).

const StringPiece &	piece (Index i) const
	Return the partons belonging to string piece with index i (note that the indices starts with 1).

Junction &	junction (Index i, bool forward)
	Return the sink (or source if forward is false) neighbors of a string piece with index i (note that the indices starts with 1).

const Junction &	junction (Index i, bool forward) const
	Return the sink (or source if forward is false) neighbors of a string piece with index i (note that the indices starts with 1).

Junction &	sink (Index i)
	Return the sink or source neighbors of a string piece with index i (note that the indices starts with 1).

const Junction &	sink (Index i) const
	Return the sink or source neighbors of a string piece with index i (note that the indices starts with 1).

Junction &	source (Index i)
	Return the sink or source neighbors of a string piece with index i (note that the indices starts with 1).

const Junction &	source (Index i) const
	Return the sink or source neighbors of a string piece with index i (note that the indices starts with 1).

tcPDVector	getTripletData () const
	Return a vector with data objects corresponding to all triplet partons in this singlet.

ColourSinglet	splitInternal (Index sp=0)
	Split a junction string. More...

ColourSinglet	splitInternal (Index sp, Index sa, Index sc, const vector< bool > &assing)
	Split a junction string. More...

ColourSinglet	splitDiQuarkJunction (Index sp, tcPPtr diq, tcPPair qq, const vector< bool > &assign=vector< bool >())
	Split a junction string. More...

ColourSinglet	splitDiDiQuark (tcPPair qq1, tcPPair qq2, const vector< bool > &assign=vector< bool >())
	Split a di-quark string. More...

void	swap (ColourSinglet &x)
	Swap this colour singlet for the argument.

Static Public Member Functions
static vector< ColourSinglet >	getSinglets (tcParticleSet &left)
	Extract colour-singlet strings/clusters of partons from the given set. More...

template<typename Iterator >
static vector< ColourSinglet >	getSinglets (Iterator first, Iterator last)
	Extract colour-singlet strings/clusters of partons from the given range of particles.

Protected Member Functions
	ColourSinglet (const ColourSinglet &cs, Index si)
	Internal constructor. More...

Private Member Functions
bool	fill (Index s0, bool forward, tcColinePtr first, tcParticleSet &left)
	Fill a string piece. More...

void	fill (Index i0, bool forward, const ColourSinglet &cs, Index i1)
	Fill a string piece. More...

Index	addPiece ()
	Add a new string piece and return its index.

Junction	addJunction (Index s0, bool forward)
	Add a junction which is a source (or sink if forward) to the string piece s0. More...

Private Attributes
tcPVector	thePartons
	The vector of all partons.

vector< StringPiece >	thePieces
	The different string pieces.

vector< Junction >	theSources
	The source neighbours of the string pieces.

vector< Junction >	theSinks
	The sink neighbours of the string pieces.

Detailed Description

A ColourSinglet object represents a set of colour-connected partons in a total colour-singlet state.

The simplest form is a single string represented by a vector of partons starting from a colour-triplet parton followed by a number of colour-octet partons and ending in a anti-triplet. A closed string is represented by a vector of colour-octet partons. If junctions are present, there will be a vector of string pieces containing the associated partons, with associated information about the string pieces connected via sinks or sources.

See also: ColourLine; Particle

Definition at line 31 of file ColourSinglet.h.

Member Typedef Documentation

◆ Index

typedef StringPiece::size_type ThePEG::ColourSinglet::Index

An integer type used as index in a string pieece.

Definition at line 38 of file ColourSinglet.h.

◆ Junction

typedef pair<Index,Index> ThePEG::ColourSinglet::Junction

Representaion of a junction.

Definition at line 40 of file ColourSinglet.h.

◆ StringPiece

typedef deque<tcPPtr> ThePEG::ColourSinglet::StringPiece

A piece of string.

Definition at line 36 of file ColourSinglet.h.

Constructor & Destructor Documentation

◆ ColourSinglet()

ThePEG::ColourSinglet::ColourSinglet	(	const ColourSinglet &	cs,
		Index	si
	)

protected

Internal constructor.

When splitting an internal line, create a new colour singlet starting from the string piece si in the singlet cs.

Member Function Documentation

◆ addJunction()

Junction ThePEG::ColourSinglet::addJunction	(	Index	s0,
		bool	forward
	)

private

Add a junction which is a source (or sink if forward) to the string piece s0.

Return the indices of the two connected string pieces.

Referenced by addPiece().

◆ fill() [1/2]

bool ThePEG::ColourSinglet::fill	(	Index	s0,
		bool	forward,
		tcColinePtr	first,
		tcParticleSet &	left
	)

private

Fill a string piece.

Follow a colour line forward in colour removing partons from the left set and adding them to the string piece s0 as we go along. If a line ends in a colour sink/source, follow the other two colour lines in turn with the value of forward reversed.

Referenced by swap().

◆ fill() [2/2]

void ThePEG::ColourSinglet::fill	(	Index	i0,
		bool	forward,
		const ColourSinglet &	cs,
		Index	i1
	)

private

Fill a string piece.

When creating a new singlet from an old one which has been split, add the string piece i1. If it ends in a sink or a source add the neighbors recursively.

◆ getSinglets()

static vector<ColourSinglet> ThePEG::ColourSinglet::getSinglets ( tcParticleSet & left )

static

Extract colour-singlet strings/clusters of partons from the given set.

The set will be empty afterwards if all went well - even colour-singlet particles will be removed.

Referenced by getSinglets(), and source().

◆ splitDiDiQuark()

ColourSinglet ThePEG::ColourSinglet::splitDiDiQuark	(	tcPPair	qq1,
		tcPPair	qq2,
		const vector< bool > &	assign = `vector< bool >()`
	)

Split a di-quark string.

If this singlet is a simple string with (anti-)diquarks in both ends, split the diquarks into the given quark pairs and create two new string pieces the betwen the quark and anit-quarks, adding the remaining partons to the first piece if the corresponding assign element is true. The singlet will then split into two - one is returned and this will contain the other. Note that the parent-children relationship and colour flows of the diquark and the two quarks is not handled by this function.

Referenced by getSinglets().

◆ splitDiQuarkJunction()

ColourSinglet ThePEG::ColourSinglet::splitDiQuarkJunction	(	Index	sp,
		tcPPtr	diq,
		tcPPair	qq,
		const vector< bool > &	assign = `vector< bool >()`
	)

Split a junction string.

If a sting piece sp is connected to a junction and ends in a diquark diq, split the diquark into two quarks, remove the junction, adding the other partons to the first neighbouring string piece if the corresponding assign element is true. The singlet will then split into two - one is returned and this will contain the other. Note that the parent-children relationship and colour flows of the diquark and the two quarks is not handled by this function.

Referenced by getSinglets().

◆ splitInternal() [1/2]

ColourSinglet ThePEG::ColourSinglet::splitInternal ( Index sp = 0 )

Split a junction string.

Split an internal string piece sp (one that starts from a source and ends in a sink). Randomly pair together the connectin string pieces and randomly assign possible colour octet partons to the two joined string pieces. The singlet will then split into two - one is returned and this will contain the other. If no argument is given, a random internal line will be picked.

Referenced by getSinglets().

◆ splitInternal() [2/2]

ColourSinglet ThePEG::ColourSinglet::splitInternal	(	Index	sp,
		Index	sa,
		Index	sc,
		const vector< bool > &	assing
	)

Split a junction string.

Split an internal string piece sp (one that starts from a source and ends in a sink). The source neighbour sa will be joined with the sink neighbour sc. Possible colour octet partons in the split string piece will be assigned to the joined sa-sc string piece if the corresponing assign element is true. The singlet will then split into two - one is returned and this will contain the other.

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

ColourSinglet.h

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Private Member Functions

Private Attributes

Detailed Description

Member Typedef Documentation

◆ Index

◆ Junction

◆ StringPiece

Constructor & Destructor Documentation

◆ ColourSinglet()

Member Function Documentation

◆ addJunction()

◆ fill() [1/2]

◆ fill() [2/2]

◆ getSinglets()

◆ splitDiDiQuark()

◆ splitDiQuarkJunction()

◆ splitInternal() [1/2]

◆ splitInternal() [2/2]