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Herwig++  2.7.0
Herwig::MEPP2ZHPowheg Class Reference

The MEPP2ZHPowheg class implements the matrix element for $q\bar{q}\to Z^0h^0$. More...

#include <MEPP2ZHPowheg.h>

Inheritance diagram for Herwig::MEPP2ZHPowheg:

List of all members.

Public Member Functions

 MEPP2ZHPowheg ()
 The default constructor.
Virtual functions required by the MEBase class.
virtual Energy2 scale () const
 Return the scale associated with the last set phase space point.
virtual int nDim () const
 The number of internal degreed of freedom used in the matrix element.
virtual bool generateKinematics (const double *r)
 Generate internal degrees of freedom given 'nDim()' uniform random numbers in the interval ]0,1[.
virtual CrossSection dSigHatDR () const
 Return the matrix element for the kinematical configuation previously provided by the last call to setKinematics().
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 Public Member Functions

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

Protected Member Functions

double NLOweight () const
 Calculate the correction weight with which leading-order configurations are re-weighted.
double x (double xt, double v) const
 Calculate the variable $x=M_{B}^2/s$ from the integration variables.
double x_a (double x, double v) const
 Calculate the momentum fraction of the first parton.
double x_b (double x, double v) const
 Calculate the momentum fraction of second parton.
double xbar (double v) const
 Calculate the minimum of $x$.
double Ltilde_qg (double x, double v) const
 Calculate the ratio of the radiative luminosity funcion to the Born luminosity function for the $qg$ initiated channel.
double Ltilde_gq (double x, double v) const
 Calculate the ratio of the radiative luminosity funcion to the Born luminosity function for the $g\bar{q}$ initiated channel.
double Ltilde_qq (double x, double v) const
 Calculate the ratio of the radiative luminosity funcion to the Born luminosity function for the $q\bar{q}$ initiated channel.
double Vtilde_qq () const
 Calculate the soft-virtual contribution to the NLO weight.
double Ccalbar_qg (double x) const
 Function for calculation of the $g\bar{q}$ and $g\bar{q}$ initiated real contribution.
double Fcal_qg (double x, double v) const
 Function for calculation of the $qg$ initiated real contribution.
double Fcal_gq (double x, double v) const
 Function for calculation of the $g\bar{q}$ initiated real contribution.
double Fcal_qq (double x, double v) const
 Function for calculation of the $q\bar{q}$ initiated real contribution.
double Ftilde_qg (double xt, double v) const
 Function for calculation of the $qg$ initiated real contribution.
double Ftilde_gq (double xt, double v) const
 Function for calculation of the $g\bar{q}$ initiated real contribution.
double Ftilde_qq (double xt, double v) const
 Function for calculation of the $q\bar{q}$ initiated real contribution.
double Ctilde_qg (double x, double v) const
 Function for calculation of the $qg$ initiated real contribution.
double Ctilde_gq (double x, double v) const
 Function for calculation of the $g\bar{q}$ initiated real contribution.
double Ctilde_qq (double x, double v) const
 Function for calculation of the $q\bar{q}$ initiated real contribution.
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.
Standard Interfaced functions.
virtual void doinit ()
 Initialize this object after the setup phase before saving an EventGenerator to disk.

Private Member Functions

MEPP2ZHPowhegoperator= (const MEPP2ZHPowheg &)
 The assignment operator is private and must never be called.

Private Attributes

double _xb_a
 The momentum fraction of the first parton in the Born process.
double _xb_b
 The momentum fraction of the second parton in the Born process.
tcPDPtr _parton_a
 The ParticleData object for the first parton in the Born process.
tcPDPtr _parton_b
 The ParticleData object for the second parton in the Born process.
Ptr< BeamParticleData >
::transient_const_pointer 
_hadron_A
 The BeamParticleData object for the first hadron.
Ptr< BeamParticleData >
::transient_const_pointer 
_hadron_B
 The BeamParticleData object for the second hadron.
tcPDPtr _gluon
 the ParticleData object for the gluon
const double TR_
 The $T_R$ colour factor.
const double CF_
 The $C_F$ colour factor.
double _alphaS2Pi
 The value of $\frac{\alpha_S}{2\pi}$ used for the calculation.
Energy2 _mll2
 The mass squared of the lepton pair.
Energy2 _mu2
 The renormalization/factorization scale.
unsigned int _contrib
 Parameters for the NLO weight.
unsigned int _nlo_alphaS_opt
 Whether to use a fixed or a running QCD coupling for the NLO weight.
double _fixed_alphaS
 The value of alphaS to use for the nlo weight if _nloalphaSopt=1.
double _a
 The magnitude of the correction term to reduce the negative contribution.
double _p
 The power of the correction term to reduce the negative contribution.
double _eps
 Cut-off for the correction function.
unsigned int _scaleopt
 Choice of the scale.
Energy _fixedScale
 Fixed scale if used.
double _scaleFact
 Prefactor if variable scale used.
double _xt
 Radiation variables.
double _v
 The $v$ angular variable.
double _oldq
 Values of the PDF's before radiation.
double _oldqbar
 For the antiquark.

Static Private Attributes

static ClassDescription
< MEPP2ZHPowheg
initMEPP2ZHPowheg
 The static object used to initialize the description of this class.

Detailed Description

The MEPP2ZHPowheg class implements the matrix element for $q\bar{q}\to Z^0h^0$.

See also:
The interfaces defined for MEPP2ZHPowheg.

Definition at line 22 of file MEPP2ZHPowheg.h.


Member Function Documentation

virtual IBPtr Herwig::MEPP2ZHPowheg::clone ( ) const [inline, protected, virtual]

Make a simple clone of this object.

Returns:
a pointer to the new object.

Reimplemented from Herwig::MEPP2ZH.

Definition at line 205 of file MEPP2ZHPowheg.h.

virtual void Herwig::MEPP2ZHPowheg::doinit ( ) [protected, virtual]

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

Exceptions:
InitExceptionif object could not be initialized properly.

Reimplemented from Herwig::MEPP2ZH.

virtual CrossSection Herwig::MEPP2ZHPowheg::dSigHatDR ( ) const [virtual]

Return the matrix element for the kinematical configuation previously provided by the last call to setKinematics().

Uses me().

Reimplemented from Herwig::MEfftoVH.

virtual IBPtr Herwig::MEPP2ZHPowheg::fullclone ( ) const [inline, protected, virtual]

Make a clone of this object, possibly modifying the cloned object to make it sane.

Returns:
a pointer to the new object.

Reimplemented from Herwig::MEPP2ZH.

Definition at line 211 of file MEPP2ZHPowheg.h.

virtual bool Herwig::MEPP2ZHPowheg::generateKinematics ( const double *  r) [virtual]

Generate internal degrees of freedom given 'nDim()' uniform random numbers in the interval ]0,1[.

To help the phase space generator, the 'dSigHatDR()' should be a smooth function of these numbers, although this is not strictly necessary. Return false if the chosen points failed the kinematical cuts.

Reimplemented from Herwig::MEfftoVH.

static void Herwig::MEPP2ZHPowheg::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.

Reimplemented from Herwig::MEPP2ZH.

MEPP2ZHPowheg& Herwig::MEPP2ZHPowheg::operator= ( const MEPP2ZHPowheg ) [private]

The assignment operator is private and must never be called.

In fact, it should not even be implemented.

Function used to read in object persistently.

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

Reimplemented from Herwig::MEPP2ZH.

Function used to write out object persistently.

Parameters:
osthe persistent output stream written to.

Reimplemented from Herwig::MEPP2ZH.


Member Data Documentation

unsigned int Herwig::MEPP2ZHPowheg::_contrib [private]

Parameters for the NLO weight.

Whether to generate the positive, negative or leading order contribution

Definition at line 309 of file MEPP2ZHPowheg.h.

double Herwig::MEPP2ZHPowheg::_oldq [mutable, private]

Values of the PDF's before radiation.

For the quark

Definition at line 379 of file MEPP2ZHPowheg.h.

unsigned int Herwig::MEPP2ZHPowheg::_scaleopt [private]

Choice of the scale.

Type of scale

Definition at line 344 of file MEPP2ZHPowheg.h.

double Herwig::MEPP2ZHPowheg::_xt [private]

Radiation variables.

The $\tilde{x}$ variable

Definition at line 364 of file MEPP2ZHPowheg.h.

The static object used to initialize the description of this class.

Indicates that this is a concrete class with persistent data.

Definition at line 232 of file MEPP2ZHPowheg.h.


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