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Herwig  7.1.5
Herwig::ShowerKinematics Class Reference

This is the abstract base class from which all other shower kinematics classes derive. More...

#include <ShowerKinematics.h>

Inheritance diagram for Herwig::ShowerKinematics:

Public Member Functions

 ShowerKinematics ()
 The default constructor.
 
tSudakovPtr SudakovFormFactor () const
 Set and get methods for the SudakovFormFactor object. More...
 
void SudakovFormFactor (const tSudakovPtr sud)
 Set the SudakovFormFactor object responsible of the eventual branching of this particle.
 
virtual void updateChildren (const tShowerParticlePtr parent, const ShowerParticleVector &children, ShowerPartnerType partnerType, bool massVeto) const
 The updateChildren and updateParent members to update the values of the $\alpha$ and $p_\perp$ variables during the shower evolution. More...
 
virtual void resetChildren (const tShowerParticlePtr parent, const ShowerParticleVector &children) const
 
virtual void updateParent (const tShowerParticlePtr parent, const ShowerParticleVector &children, ShowerPartnerType partnerType) const
 Update the parent Kinematics from the knowledge of the kinematics of the children. More...
 
virtual void updateLast (const tShowerParticlePtr last, Energy px, Energy py) const
 Update the kinematical data of a particle when a reconstruction fixpoint was found. More...
 
virtual void reconstructChildren (const tShowerParticlePtr parent, const ShowerParticleVector &children) const
 The reconstructLast, reconstructChildren and reconstructParent members are used during the reconstruction. More...
 
virtual void reconstructParent (const tShowerParticlePtr parent, const ParticleVector &children) const
 Reconstruct the parent Kinematics from the knowledge of the kinematics of the children. More...
 
virtual void reconstructLast (const tShowerParticlePtr last, Energy mass=-1.*GeV) const
 Update the kinematical data of a particle when a reconstruction fixpoint was found. More...
 
void isTheJetStartingPoint (const bool)
 Set/access the flag that tells whether or not this ShowerKinematics object is associated to the starting particle of the jet: only in this case it is sensible to use the two main virtual methods below. More...
 
bool isTheJetStartingPoint () const
 Get the starting point flag.
 
Energy scale () const
 Set/Get methods for the kinematic variables. More...
 
void scale (const Energy in)
 Set the scale of the splitting.
 
double z () const
 Access the energy fraction, $z$.
 
void z (const double in)
 Set the energy fraction, $z$.
 
double phi () const
 Access the azimuthal angle, $\phi$.
 
void phi (const double in)
 Set the azimuthal angle, $\phi$.
 
Energy pT () const
 Access the relative $p_T$ for the branching.
 
void pT (const Energy in) const
 Set the relative $p_T$ for the branching.
 
tSplittingFnPtr splittingFn () const
 Set and get methods for the SplittingFunction object. More...
 
- 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
 

Private Member Functions

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

Private Attributes

bool _isTheJetStartingPoint
 Is this the starting point of the jet.
 
Energy _scale
 The $\tilde{q}$ evolution variable.
 
double _z
 The energy fraction, $z$.
 
double _phi
 The azimuthal angle, $\phi$.
 
Energy _pt
 The relative $p_T$.
 
tSudakovPtr _sudakov
 The splitting function for the branching of the particle.
 

Additional Inherited Members

- Public Types inherited from ThePEG::Pointer::ReferenceCounted
typedef unsigned int CounterType
 
- Static Public Member Functions inherited from ThePEG::Base
static void Init ()
 
- Public Attributes inherited from ThePEG::Pointer::ReferenceCounted
const unsigned long uniqueId
 
- Protected Member Functions inherited from ThePEG::Pointer::ReferenceCounted
 ReferenceCounted (const ReferenceCounted &)
 
ReferenceCountedoperator= (const ReferenceCounted &)
 
 ReferenceCounted (const ReferenceCounted &)
 
ReferenceCountedoperator= (const ReferenceCounted &)
 

Detailed Description

This is the abstract base class from which all other shower kinematics classes derive.

The main purpose of the shower kinematics classes is to allow the reconstruction of jet masses, at the end of the showering (indeed, for multi-scale showering, at the end of each scale-range evolution). This is necessary for the kinematics reshuffling in order to compensate the recoil of the emissions. The KinematicsReconstructor class is in charge of this job, and which is the main "user" of ShowerKinematics and its derived classes. How this is done depends on the choice of kinematics variables and whether the jet is time-like (forward evolved) or space-like (backward evolved), whereas the class ShowerKinematics describes only the common features which are independent by them.

In general there are a number of methods specific to a shower approach

See also
KinematicsReconstructor

Definition at line 45 of file ShowerKinematics.h.

Member Function Documentation

◆ isTheJetStartingPoint()

void Herwig::ShowerKinematics::isTheJetStartingPoint ( const bool  )

Set/access the flag that tells whether or not this ShowerKinematics object is associated to the starting particle of the jet: only in this case it is sensible to use the two main virtual methods below.

Set the starting point flag

◆ operator=()

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

The assignment operator is private and must never be called.

In fact, it should not even be implemented.

◆ reconstructChildren()

virtual void Herwig::ShowerKinematics::reconstructChildren ( const tShowerParticlePtr  parent,
const ShowerParticleVector children 
) const
virtual

The reconstructLast, reconstructChildren and reconstructParent members are used during the reconstruction.

Along with the showering evolution — going forward for time-like (forward) evolution, and going backward for space-like (backward) evolution — the kinematical variables of the branching products are calculated and updated from the knowledge of the parent kinematics.

Parameters
parentThe parent
childrenThe children

◆ reconstructLast()

virtual void Herwig::ShowerKinematics::reconstructLast ( const tShowerParticlePtr  last,
Energy  mass = -1.*GeV 
) const
virtual

Update the kinematical data of a particle when a reconstruction fixpoint was found.

This will highly depend on the kind of kinematics chosen and will be defined in the inherited concrete classes. This method will be used by the KinematicsReconstructor.

Parameters
lastThe particle.
massThe mass to be used, if less than zero on-shell

Reimplemented in Herwig::FS_QTildeShowerKinematics1to2, and Herwig::Decay_QTildeShowerKinematics1to2.

◆ reconstructParent()

virtual void Herwig::ShowerKinematics::reconstructParent ( const tShowerParticlePtr  parent,
const ParticleVector children 
) const
virtual

Reconstruct the parent Kinematics from the knowledge of the kinematics of the children.

This method will be used by the KinematicsReconstructor.

Parameters
parentThe parent
childrenThe children

Reimplemented in Herwig::FS_QTildeShowerKinematics1to2, Herwig::IS_QTildeShowerKinematics1to2, and Herwig::Decay_QTildeShowerKinematics1to2.

◆ scale()

Energy Herwig::ShowerKinematics::scale ( ) const
inline

Set/Get methods for the kinematic variables.

Access the scale of the splitting.

Definition at line 167 of file ShowerKinematics.h.

◆ splittingFn()

tSplittingFnPtr Herwig::ShowerKinematics::splittingFn ( ) const
inline

Set and get methods for the SplittingFunction object.

Access the SplittingFunction object responsible of the eventual branching of this particle.

Definition at line 213 of file ShowerKinematics.h.

References splittingFn().

Referenced by splittingFn().

◆ SudakovFormFactor()

tSudakovPtr Herwig::ShowerKinematics::SudakovFormFactor ( ) const
inline

Set and get methods for the SudakovFormFactor object.

Access the SudakovFormFactor object responsible of the eventual branching of this particle.

Definition at line 223 of file ShowerKinematics.h.

◆ updateChildren()

virtual void Herwig::ShowerKinematics::updateChildren ( const tShowerParticlePtr  parent,
const ShowerParticleVector children,
ShowerPartnerType  partnerType,
bool  massVeto 
) const
virtual

The updateChildren and updateParent members to update the values of the $\alpha$ and $p_\perp$ variables during the shower evolution.

Along with the showering evolution — going forward for time-like (forward) evolution, and going backward for space-like (backward) evolution — the kinematical variables of the branching products are calculated and updated from the knowledge of the parent kinematics.

Parameters
parentThe parent
childrenThe children
partnerTypeThe type of evolution partner

Reimplemented in Herwig::FS_QTildeShowerKinematics1to2, Herwig::IS_QTildeShowerKinematics1to2, and Herwig::Decay_QTildeShowerKinematics1to2.

◆ updateLast()

virtual void Herwig::ShowerKinematics::updateLast ( const tShowerParticlePtr  last,
Energy  px,
Energy  py 
) const
virtual

Update the kinematical data of a particle when a reconstruction fixpoint was found.

This will highly depend on the kind of kinematics chosen and will be defined in the inherited concrete classes. This method will be used by the KinematicsReconstructor.

Parameters
lastThe particle.
pxThe $x$ component of the $p_T$.
pyThe $y$ component of the $p_T$.

Reimplemented in Herwig::IS_QTildeShowerKinematics1to2.

◆ updateParent()

virtual void Herwig::ShowerKinematics::updateParent ( const tShowerParticlePtr  parent,
const ShowerParticleVector children,
ShowerPartnerType  partnerType 
) const
virtual

Update the parent Kinematics from the knowledge of the kinematics of the children.

This method will be used by the KinematicsReconstructor.

Parameters
parentThe parent
childrenThe children
partnerTypeThe type of evolution partner

Reimplemented in Herwig::Decay_QTildeShowerKinematics1to2, Herwig::FS_QTildeShowerKinematics1to2, and Herwig::IS_QTildeShowerKinematics1to2.


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