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Herwig  7.2.1
Herwig::DensityOperator Class Reference

Here is the documentation of the DensityOperator class. More...

#include <DensityOperator.h>

Inheritance diagram for Herwig::DensityOperator:

Public Member Functions

void clear ()
 Clears theDensityOperatorMap.
 
void prepare (const cPDVector &)
 Prepare for the given sub process.
 
void fill (const Ptr< MatchboxXComb >::ptr, const cPDVector &, const vector< Lorentz5Momentum > &momenta)
 Fill the density operator for the given hard subprocess, summing over all helicity configurations.
 
void evolve (const map< pair< size_t, size_t >, Complex > &Vijk, const cPDVector &before, const cPDVector &after, const map< std::tuple< size_t, size_t, size_t >, map< size_t, size_t > > &emissionsMap, const bool splitAGluon, const bool initialGluonSplitting)
 Evolve the density operator, by M_{n+1} = -{i,k}{-4*pi*alpha_s/Ti2*V_{ij,k} T_{i,n}M_nT_{k,n}^}, see arXiv:1206.0180 eq. More...
 
double colourMatrixElementCorrection (const std::tuple< size_t, size_t, long > &ikemission, const cPDVector &particles)
 Calculate the colour matrix element correction. More...
 
void colourConservation (const cPDVector &particles)
 Checking colour conservation for the colour matrix element corrections.
 
Ptr< ColourBasis >::tptr colourBasis ()
 Get the colour basis.
 
const Ptr< ColourBasis >::tptr colourBasis () const
 Get the colour basis.
 
void colourBasis (Ptr< ColourBasis >::ptr ptr)
 Set the colour basis.
 
const map< pair< vector< PDT::Colour >, pair< size_t, size_t > >, double > & correlatorMap () const
 Get the correlator map.
 
Standard constructors and destructors.
 DensityOperator ()
 The default constructor.
 
virtual ~DensityOperator ()
 The destructor.
 
Functions used by the persistent I/O system.
void persistentOutput (PersistentOStream &os) const
 Function used to write out object persistently. More...
 
void persistentInput (PersistentIStream &is, int version)
 Function used to read in object persistently. More...
 
- Public Member Functions inherited from 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
 
void persistentOutput (PersistentOStream &os) const
 
void persistentInput (PersistentIStream &is, int version)
 
- Public Member Functions inherited from ThePEG::InterfacedBase
string fullName () const
 
string name () const
 
string path () const
 
string comment () const
 
void setup (istream &is)
 
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
 
void persistentOutput (PersistentOStream &os) const
 
void persistentInput (PersistentIStream &is, int version)
 
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
 
void persistentOutput (PersistentOStream &os) const
 
void persistentInput (PersistentIStream &is, int version)
 
- Public Member Functions inherited from ThePEG::Base
void debug () 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
 

Static Public Member Functions

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

Protected Member Functions

Clone Methods.
virtual IBPtr clone () const
 Make a simple clone of this object. More...
 
virtual IBPtr fullclone () const
 Make a clone of this object, possibly modifying the cloned object to make it sane. More...
 
- 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
 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 &)
 
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 &)
 
ReferenceCountedoperator= (const ReferenceCounted &)
 
 ReferenceCounted (const ReferenceCounted &)
 
ReferenceCountedoperator= (const ReferenceCounted &)
 
- Protected Member Functions inherited from ThePEG::Named
const Namedoperator= (const Named &other)
 
const string & name (const string &newName)
 

Private Member Functions

double colourNorm (const cPDPtr particle)
 Normalization of colour charges {T}_{ij}^2.
 
matrix< ComplexprodSparseDense (const compressed_matrix< double > &, const matrix< Complex > &)
 Fast evaluation of Tij*Mn, where a Tij is the matrix from ColourBasis::charge, which is a sparse matrix, and Mn is the density operator, a dense matrix.
 
matrix< ComplexprodDenseSparse (const matrix< Complex > &, const compressed_matrix< double > &)
 Fast evaluation of TijMn*Tkdagger, where a TijMn is the result from the method prodSparseDense, a dense matrix, and Tkdagger is the transponse conjugate of the matrix from ColourBasis::charge, a sparse matrix.
 
vector< Lorentz5Momentum > boostToRestFrame (const vector< Lorentz5Momentum > &momenta)
 Boosts a vector of momenta to the rest frame of the initial pair of particles (the first 2 elements of the argument vector). More...
 
bool compareMomentum (const Lorentz5Momentum &p, const Lorentz5Momentum &q)
 Boosts a vector of momenta to the rest frame of the initial pair.
 
DensityOperatoroperator= (const DensityOperator &)
 The assignment operator is private and must never be called. More...
 

Private Attributes

double Nc
 Number of colours used in colourNorm.
 
double TR
 QCD vertex normalization.
 
map< vector< PDT::Colour >, matrix< Complex > > theDensityOperatorMap
 Mapping of colour structures to density operator matrices.
 
map< pair< vector< PDT::Colour >, pair< size_t, size_t > >, double > theCorrelatorMap
 Mapping of colour structures and legs to colour correlators.
 
map< cPDVector, map< size_t, size_t > > theColourBasisToColourBasisMap
 A map from the hard subprocess particles to a map of amplitude colour basis order to the normal ordered colour basis.
 
Ptr< ColourBasis >::ptr theColourBasis
 Colour basis used.
 

Additional Inherited Members

- Public Types inherited from ThePEG::InterfacedBase
enum  InitState
 
- Public Types inherited from ThePEG::Pointer::ReferenceCounted
typedef unsigned int CounterType
 
- 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)
 

Detailed Description

Here is the documentation of the DensityOperator class.

See also
The interfaces defined for DensityOperator.

Definition at line 37 of file DensityOperator.h.

Member Function Documentation

◆ boostToRestFrame()

vector<Lorentz5Momentum> Herwig::DensityOperator::boostToRestFrame ( const vector< Lorentz5Momentum > &  momenta)
private

Boosts a vector of momenta to the rest frame of the initial pair of particles (the first 2 elements of the argument vector).

Returns the boosted vectors

◆ clone()

virtual IBPtr Herwig::DensityOperator::clone ( ) const
protectedvirtual

Make a simple clone of this object.

Returns
a pointer to the new object.

Implements ThePEG::InterfacedBase.

◆ colourMatrixElementCorrection()

double Herwig::DensityOperator::colourMatrixElementCorrection ( const std::tuple< size_t, size_t, long > &  ikemission,
const cPDVector particles 
)

Calculate the colour matrix element correction.

-(1+delta(i,gluon))/Ti^2 Tr(Sn+1 Ti Mn Tk^dagger)/Tr(Sn Mn) where the bracket in front compensates for the gluon symmetry factor, Ti^2 is C_f or C_a, Sn+1 is the matrix of scalar products, and Ti is the radiation matrix. The first arg contains (emitter index, spectator index, emission pid)

◆ evolve()

void Herwig::DensityOperator::evolve ( const map< pair< size_t, size_t >, Complex > &  Vijk,
const cPDVector before,
const cPDVector after,
const map< std::tuple< size_t, size_t, size_t >, map< size_t, size_t > > &  emissionsMap,
const bool  splitAGluon,
const bool  initialGluonSplitting 
)

Evolve the density operator, by M_{n+1} = -{i,k}{-4*pi*alpha_s/Ti2*V_{ij,k} T_{i,n}M_nT_{k,n}^}, see arXiv:1206.0180 eq.

(5), note that the pi*pj factor is assumed to be included in V_{ij,k}.

◆ fullclone()

virtual IBPtr Herwig::DensityOperator::fullclone ( ) const
protectedvirtual

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.

◆ Init()

static void Herwig::DensityOperator::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.

◆ operator=()

DensityOperator& Herwig::DensityOperator::operator= ( const DensityOperator )
private

The assignment operator is private and must never be called.

In fact, it should not even be implemented.

◆ persistentInput()

void Herwig::DensityOperator::persistentInput ( PersistentIStream is,
int  version 
)

Function used to read in object persistently.

Parameters
isthe persistent input stream read from.
versionthe version number of the object when written.

◆ persistentOutput()

void Herwig::DensityOperator::persistentOutput ( PersistentOStream os) const

Function used to write out object persistently.

Parameters
osthe persistent output stream written to.

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