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Herwig  7.1.5
Herwig::ThreeMesonCurrentBase Class Referenceabstract

This is the base class for the three meson decays of the weak current. More...

#include <ThreeMesonCurrentBase.h>

Inheritance diagram for Herwig::ThreeMesonCurrentBase:

Classes

struct  FormFactors
 Helper class for form factors. More...
 

Public Member Functions

 ThreeMesonCurrentBase ()
 Default constructor.
 
virtual vector< LorentzPolarizationVectorEcurrent (const int imode, const int ichan, Energy &scale, const ParticleVector &decay, DecayIntegrator::MEOption meopt) const
 Hadronic current. More...
 
virtual bool accept (vector< int > id)
 Accept the decay. More...
 
virtual unsigned int decayMode (vector< int > id)
 Return the decay mode number for a given set of particles in the current. More...
 
virtual tPDVector particles (int icharge, unsigned int imode, int iq, int ia)
 The particles produced by the current. More...
 
virtual void dataBaseOutput (ofstream &os, bool header, bool create) const
 Output the setup information for the particle database. More...
 
- Public Member Functions inherited from Herwig::WeakDecayCurrent
 WeakDecayCurrent ()
 Default constructor.
 
unsigned int numberOfModes () const
 Return the number of modes handled by this current.
 
void decayModeInfo (unsigned int imode, int &iq, int &ia) const
 Information on a decay mode. More...
 
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. More...
 
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 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 IBPtr fullclone () const
 
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())
 
const string & name () const
 
bool operator== (const Named &other) const
 
bool operator< (const Named &other) const
 

Static Public Member Functions

static void Init ()
 Standard Init function used to initialize the interfaces.
 
- Static Public Member Functions inherited from Herwig::WeakDecayCurrent
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 ()
 

Protected Member Functions

virtual bool acceptMode (int imode) const =0
 can a particular decayer handle this type of mode More...
 
virtual FormFactors calculateFormFactors (const int ichan, const int imode, Energy2 q2, Energy2 s1, Energy2 s2, Energy2 s3) const =0
 Calculate the form factor for the current. More...
 
- Protected Member Functions inherited from Herwig::WeakDecayCurrent
void addDecayMode (int iq, int ia)
 Add a decay mode to the list. More...
 
void setInitialModes (unsigned int nmodes)
 Set initial number of modes. 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
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 &)
 
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

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

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

This is the base class for the three meson decays of the weak current.

It is designed so that the currents for the following modes can be implemented in classes inheriting from this

  • $ \pi^- \pi^- \pi^+ $, (imode=0)
  • $ \pi^0 \pi^0 \pi^- $, (imode=1)
  • $ K^- \pi^- K^+ $, (imode=2)
  • $ K^0 \pi^- \bar{K}^0$, (imode=3)
  • $ K^- \pi^0 K^0 $, (imode=4)
  • $ \pi^0 \pi^0 K^- $, (imode=5)
  • $ K^- \pi^- \pi^+ $, (imode=6)
  • $ \pi^- \bar{K}^0 \pi^0 $, (imode=7)
  • $ \pi^- \pi^0 \eta $, (imode=8)

obviously there are other modes with three pseudoscalar mesons for the decay of the weak current but this model original came from $\tau$ decay where these are the only modes. However one case which is important is the inclusion of the mixing in the neutral kaon sector for which we include the additional currents

  • $ K^0_S \pi^- K^0_S$, (imode=9)
  • $ K^0_L \pi^- K^0_L$, (imode=10)
  • $ K^0_S \pi^- K^0_L$, (imode=11)

    In this case the current is given by

    \[ J^\mu = \left(g^{\mu\nu}-\frac{q^\mu q^\nu}{q^2}\right) \left[F_1(p_2-p_3)^\mu +F_2(p_3-p_1)^\mu+F_3(p_1-p_2)^\mu\right] +q^\mu F_4 +F_5\epsilon^{\mu\alpha\beta\gamma}p_1^\alpha p_2^\beta p_3^\gamma \]

    where

  • $p_{1,2,3}$ are the momenta of the mesons in the order given above.
  • $F_1,F_2,F_3,F_4,F_5$ are the form factors which must be calculated in the calculateFormFactors member which should be implemented in classes inheriting from this.
See also
WeakDecayCurrent.
Author
Peter Richardson

Definition at line 59 of file ThreeMesonCurrentBase.h.

Member Function Documentation

◆ accept()

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

Accept the decay.

Checks the mesons against the list.

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

Implements Herwig::WeakDecayCurrent.

◆ acceptMode()

virtual bool Herwig::ThreeMesonCurrentBase::acceptMode ( int  imode) const
protectedpure virtual

can a particular decayer handle this type of mode

Parameters
imodeThe mode number as given above
Returns
Whether this mode can be handled.

Implemented in Herwig::ThreePionCLEOCurrent, Herwig::ThreeMesonDefaultCurrent, and Herwig::KaonThreeMesonCurrent.

◆ calculateFormFactors()

virtual FormFactors Herwig::ThreeMesonCurrentBase::calculateFormFactors ( const int  ichan,
const int  imode,
Energy2  q2,
Energy2  s1,
Energy2  s2,
Energy2  s3 
) const
protectedpure virtual

Calculate the form factor for the current.

Parameters
ichanThe phase space channel
imodeThe mode
q2The scale $q^2$ for the current.
s1The invariant mass squared of particles 2 and 3, $s_1=m^2_{23}$.
s2The invariant mass squared of particles 1 and 3, $s_2=m^2_{13}$.
s3The invariant mass squared of particles 1 and 2, $s_3=m^2_{12}$.

Implemented in Herwig::ThreePionCLEOCurrent, Herwig::ThreeMesonDefaultCurrent, and Herwig::KaonThreeMesonCurrent.

◆ current()

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

Hadronic current.

This version returns the hadronic current described above.

Parameters
imodeThe mode
ichanThe phase-space channel the current is needed for.
scaleThe invariant mass of the particles in the current.
decayThe decay products
meoptOption for the calculation of the matrix element
Returns
The current.

Implements Herwig::WeakDecayCurrent.

◆ dataBaseOutput()

virtual void Herwig::ThreeMesonCurrentBase::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::WeakDecayCurrent.

Reimplemented in Herwig::ThreePionCLEOCurrent, Herwig::ThreeMesonDefaultCurrent, and Herwig::KaonThreeMesonCurrent.

◆ decayMode()

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

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

Checks the mesons against the list.

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

Implements Herwig::WeakDecayCurrent.

◆ operator=()

ThreeMesonCurrentBase& Herwig::ThreeMesonCurrentBase::operator= ( const ThreeMesonCurrentBase )
privatedelete

The assignment operator is private and must never be called.

In fact, it should not even be implemented.

◆ particles()

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

The particles produced by the current.

This returns the mesons for the mode.

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::WeakDecayCurrent.


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