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Herwig 7.3.0
Herwig::KPiKStarCurrent Class Reference

Weak current for the production of two mesons via the \(\rho\) or \(K^*\) resonances. More...

#include <KPiKStarCurrent.h>

Inheritance diagram for Herwig::KPiKStarCurrent:

Public Member Functions

 KPiKStarCurrent ()
 Default constructor.
 
Methods for the construction of the phase space integrator.
virtual bool createMode (int icharge, tcPDPtr resonance, FlavourInfo flavour, unsigned int imode, PhaseSpaceModePtr mode, unsigned int iloc, int ires, PhaseSpaceChannel phase, Energy upp)
 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)
 The particles produced by the current.
 
virtual vector< LorentzPolarizationVectorEcurrent (tcPDPtr resonance, FlavourInfo flavour, const int imode, const int ichan, Energy &scale, const tPDVector &outgoing, const vector< Lorentz5Momentum > &momenta, DecayIntegrator::MEOption meopt) const
 Hadronic current.
 
virtual bool accept (vector< int > id)
 Accept the decay.
 
virtual unsigned int decayMode (vector< int > id)
 Return the decay mode number for a given set of particles in the current.
 
virtual void dataBaseOutput (ofstream &os, bool header, bool create) const
 Output the setup information for the particle database.
 
- Public Member Functions inherited from Herwig::WeakCurrent
 WeakCurrent ()
 Default constructor.
 
unsigned int numberOfModes () const
 Return the number of modes handled by this current.
 
virtual void constructSpinInfo (ParticleVector decay) const
 Construct the SpinInfo for the decay products.
 
void decayModeInfo (unsigned int imode, int &iq, int &ia) const
 Information on a decay mode.
 
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::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
 

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::WeakCurrent
void addDecayMode (int iq, int ia)
 Add a decay mode to the list.
 
void setInitialModes (unsigned int nmodes)
 Set initial number of modes.
 
- 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 &)
 
ReferenceCountedoperator= (const ReferenceCounted &)
 
- Protected Member Functions inherited from ThePEG::Named
const Namedoperator= (const Named &other)
 
const string & name (const string &newName)
 

Standard Interfaced functions.

vector< Complex_kwgt
 Weights for the different \(K^*\) resonances in the current, \(\alpha_k\).
 
vector< double > _kmag
 The magnitude for input.
 
vector< double > _kphase
 The phase for input.
 
int _kmodel
 Model to use for the \(K^*\) propagator.
 
bool _kstarparameters
 Option not to use the physical masses and widths for the \(K^*\).
 
vector< Energy > _kstarmasses
 The masses of the \(K^*\) resonances.
 
vector< Energy > _kstarwidths
 The masses of the \(K^*\) resonances.
 
vector< Energy > _mass
 Parameters for the Breit-Wigners.
 
vector< Energy > _width
 The widths of the resonances.
 
vector< Energy > _massa
 Masses of the decay products for the momentum calculation.
 
vector< Energy > _massb
 
vector< double > _dh
 The function \(\frac{\\hat{H}}{dq^2}\) at \(q^2=m^2\) for the GS form of the Breit-Wigner.
 
vector< Energy2 > _hres
 The function \(\\hat{H}\) at \(q^2=m^2\) for the GS form of the Breit-Wigner.
 
vector< Energy2 > _h0
 The \(H(0)\) parameter for the GS form of the Breit-Wigner.
 
virtual void doinit ()
 Initialize this object after the setup phase before saving and EventGenerator to disk.
 
KPiKStarCurrentoperator= (const KPiKStarCurrent &)=delete
 Private and non-existent assignment operator.
 
Complex BreitWigner (Energy2 q2, unsigned int imodel, unsigned int ires) const
 \(p\)-wave breit wigner for form-factors
 

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 ()
 Standard Init function used to initialize the interfaces.
 

Additional Inherited Members

- Public Types inherited from ThePEG::InterfacedBase
enum  InitState
 
- Public Types inherited from ThePEG::Pointer::ReferenceCounted
typedef unsigned int CounterType
 
- Static Public Member Functions inherited from Herwig::WeakCurrent
static void Init ()
 Standard Init function used to initialize the interfaces.
 
- 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)
 

Detailed Description

Weak current for the production of two mesons via the \(\rho\) or \(K^*\) resonances.

These currents are taken from tau decays.

The current takes the form

\[J^\mu = \frac{\sqrt{2}}{\sum_k\alpha_k}\left((p_1-p_2)^\mu-\frac{(p_1-p_2)\cdot q}{q^2}q^\mu))\right) \sum_k \alpha_k B_{R_k}(q^2) \]

where

  • \(p_{1,2}\) are the momenta of the outgoing mesons,
  • \(q=p_1+p_2\),
  • \(B_{R_k}(q^2)\) is the Breit-Wigner distribution for the intermediate vector meson \(R_k\).
  • \(\alpha_k\) is the weight for the resonance.

    The Breit-Wigner term is summed over the \(\rho\) or \(K^*\) resonances that can contribute to a given decay.

The models of either Kuhn and Santamaria (Z. Phys. C48, 445 (1990)) or Gounaris and Sakurai Phys. Rev. Lett. 21, 244 (1968) are supported for the shape of the Breit-Wigner distribution. The mixing parameters are taken from Phys.Rev.D61:112002,2000 (CLEO) for the decay \(\pi^\pm\pi^0\) and the CLEO version of TAUOLA for the \(K\pi\) decays.

See also
WeakCurrent.
Author
Peter Richardson

Definition at line 54 of file KPiKStarCurrent.h.

Member Function Documentation

◆ accept()

virtual bool Herwig::KPiKStarCurrent::accept ( vector< int >  id)
virtual

Accept the decay.

Checks the particles are the allowed mode.

Parameters
idThe id's of the particles in the current.
Returns
Can this current have the external particles specified.

Implements Herwig::WeakCurrent.

◆ BreitWigner()

Complex Herwig::KPiKStarCurrent::BreitWigner ( Energy2  q2,
unsigned int  imodel,
unsigned int  ires 
) const
inlineprivate

\(p\)-wave breit wigner for form-factors

Parameters
q2The scale \(q^2\) for the Breit-Wigner
imodelWhich of the two models for the Breit-Wigner shape to use.
iresWhich of the different multiplets to use.
Returns
The value of the Breit-Wigner distribution.

Definition at line 213 of file KPiKStarCurrent.h.

References _dh, _h0, _hres, _mass, _massa, and _width.

◆ clone()

virtual IBPtr Herwig::KPiKStarCurrent::clone ( ) const
inlineprotectedvirtual

Make a simple clone of this object.

Returns
a pointer to the new object.

Implements ThePEG::InterfacedBase.

Definition at line 175 of file KPiKStarCurrent.h.

◆ createMode()

virtual bool Herwig::KPiKStarCurrent::createMode ( int  icharge,
tcPDPtr  resonance,
FlavourInfo  flavour,
unsigned int  imode,
PhaseSpaceModePtr  mode,
unsigned int  iloc,
int  ires,
PhaseSpaceChannel  phase,
Energy  upp 
)
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 WeakCurrent.

Parameters
ichargeThe total charge of the outgoing particles in the current.
resonanceIf specified only include terms with this particle
flavourInformation on the required flavours of the quarks
imodeThe mode in the current being asked for.
modeThe phase space mode for the integration
ilocThe location of the of the first particle from the current in the list of outgoing particles.
iresThe location of the first intermediate for the current.
phaseThe prototype phase space channel for the integration.
uppThe maximum possible mass the particles in the current are allowed to have.
Returns
Whether the current was sucessfully constructed.

Implements Herwig::WeakCurrent.

◆ current()

virtual vector< LorentzPolarizationVectorE > Herwig::KPiKStarCurrent::current ( tcPDPtr  resonance,
FlavourInfo  flavour,
const int  imode,
const int  ichan,
Energy &  scale,
const tPDVector outgoing,
const vector< Lorentz5Momentum > &  momenta,
DecayIntegrator::MEOption  meopt 
) const
virtual

Hadronic current.

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

Parameters
resonanceIf specified only include terms with this particle
flavourInformation on the required flavours of the quarks
imodeThe mode
ichanThe phase-space channel the current is needed for.
scaleThe invariant mass of the particles in the current.
outgoingThe particles produced in the decay
momentaThe momenta of the particles produced in the decay
meoptOption for the calculation of the matrix element
Returns
The current.

Implements Herwig::WeakCurrent.

◆ dataBaseOutput()

virtual void Herwig::KPiKStarCurrent::dataBaseOutput ( ofstream &  os,
bool  header,
bool  create 
) const
virtual

Output the setup information for the particle database.

Parameters
osThe stream to output the information to
headerWhether or not to output the information for MySQL
createWhether or not to add a statement creating the object

Reimplemented from Herwig::WeakCurrent.

◆ decayMode()

virtual unsigned int Herwig::KPiKStarCurrent::decayMode ( vector< int >  id)
virtual

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

Parameters
idThe id's of the particles in the current.
Returns
The number of the mode

Implements Herwig::WeakCurrent.

◆ doinit()

virtual void Herwig::KPiKStarCurrent::doinit ( )
protectedvirtual

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

Exceptions
InitExceptionif object could not be initialized properly.

Reimplemented from ThePEG::InterfacedBase.

◆ fullclone()

virtual IBPtr Herwig::KPiKStarCurrent::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 181 of file KPiKStarCurrent.h.

◆ particles()

virtual tPDVector Herwig::KPiKStarCurrent::particles ( int  icharge,
unsigned int  imode,
int  iq,
int  ia 
)
virtual

The particles produced by the current.

This just returns the two pseudoscalar mesons and the photon.

Parameters
ichargeThe total charge of the particles in the current.
imodeThe mode for which the particles are being requested
iqThe PDG code for the quark
iaThe PDG code for the antiquark
Returns
The external particles for the current.

Implements Herwig::WeakCurrent.

◆ persistentInput()

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

Function used to write out object persistently.

Parameters
osthe persistent output stream written to.

Member Data Documentation

◆ _dh

vector<double> Herwig::KPiKStarCurrent::_dh
private

The function \(\frac{\\hat{H}}{dq^2}\) at \(q^2=m^2\) for the GS form of the Breit-Wigner.

Definition at line 295 of file KPiKStarCurrent.h.

Referenced by BreitWigner().

◆ _h0

vector<Energy2> Herwig::KPiKStarCurrent::_h0
private

The \(H(0)\) parameter for the GS form of the Breit-Wigner.

Definition at line 307 of file KPiKStarCurrent.h.

Referenced by BreitWigner().

◆ _hres

vector<Energy2> Herwig::KPiKStarCurrent::_hres
private

The function \(\\hat{H}\) at \(q^2=m^2\) for the GS form of the Breit-Wigner.

Definition at line 301 of file KPiKStarCurrent.h.

Referenced by BreitWigner().

◆ _kmag

vector<double> Herwig::KPiKStarCurrent::_kmag
private

The magnitude for input.

Definition at line 244 of file KPiKStarCurrent.h.

◆ _kmodel

int Herwig::KPiKStarCurrent::_kmodel
private

Model to use for the \(K^*\) propagator.

Definition at line 255 of file KPiKStarCurrent.h.

◆ _kphase

vector<double> Herwig::KPiKStarCurrent::_kphase
private

The phase for input.

Definition at line 249 of file KPiKStarCurrent.h.

◆ _kstarmasses

vector<Energy> Herwig::KPiKStarCurrent::_kstarmasses
private

The masses of the \(K^*\) resonances.

Definition at line 265 of file KPiKStarCurrent.h.

◆ _kstarparameters

bool Herwig::KPiKStarCurrent::_kstarparameters
private

Option not to use the physical masses and widths for the \(K^*\).

Definition at line 260 of file KPiKStarCurrent.h.

◆ _kstarwidths

vector<Energy> Herwig::KPiKStarCurrent::_kstarwidths
private

The masses of the \(K^*\) resonances.

Definition at line 270 of file KPiKStarCurrent.h.

◆ _kwgt

vector<Complex> Herwig::KPiKStarCurrent::_kwgt
private

Weights for the different \(K^*\) resonances in the current, \(\alpha_k\).

The Complex weight used in the calculation

Definition at line 239 of file KPiKStarCurrent.h.

◆ _mass

vector<Energy> Herwig::KPiKStarCurrent::_mass
private

Parameters for the Breit-Wigners.

The masses of the resonances

Definition at line 279 of file KPiKStarCurrent.h.

Referenced by BreitWigner().

◆ _massa

vector<Energy> Herwig::KPiKStarCurrent::_massa
private

Masses of the decay products for the momentum calculation.

Definition at line 289 of file KPiKStarCurrent.h.

Referenced by BreitWigner().

◆ _massb

vector<Energy> Herwig::KPiKStarCurrent::_massb
private

Definition at line 289 of file KPiKStarCurrent.h.

◆ _width

vector<Energy> Herwig::KPiKStarCurrent::_width
private

The widths of the resonances.

Definition at line 284 of file KPiKStarCurrent.h.

Referenced by BreitWigner().


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