apfel::AlphaQCDg Class Reference

The AlphaQCDg is a specialization class of the MatchedEvolution class for the computation of the QCD coupling running using the analytic g functions. More...

#include <alphaqcdg.h>

Inheritance diagram for apfel::AlphaQCDg:

Public Member Functions
double	MatchObject (bool const &Up, int const &nf, double const &Coup) const
	Function for the computation of the matching.
double	Derivative (int const &, double const &, double const &) const
	Dummy function used to overload a purely virtual function. It should be never called.
double	EvolveObject (int const &nf, double const &lnmu02, double const &lnmu2, double const &as0) const
	Function for the computation of the evolution.
Constructors
List of constructors.
	AlphaQCDg ()=delete
	AlphaQCDg (double const &AlphaRef, double const &MuRef, std::vector< double > const &Masses, std::vector< double > const &Thresholds, int const &pt, double const &kappa=1)
	AlphaQCDg constructor.
	AlphaQCDg (double const &AlphaRef, double const &MuRef, std::vector< double > const &Masses, int const &pt, double const &kappa=1)
	AlphaQCDg constructor.
Public Member Functions inherited from apfel::MatchedEvolution< double >
	MatchedEvolution ()=delete
	MatchedEvolution (double const &ObjRef, double const &MuRef, std::vector< double > const &Thresholds, int const &nsteps=10)
	The MatchedEvolution constructor.
virtual	~MatchedEvolution ()=default
double	Evaluate (double const &mu) const
	Function that returns the evolved object.
double	GetObjectRef () const
	Function that returns the reference value of the object.
double	GetMuRef () const
	Function that returns the reference scale.
std::vector< double >	GetThresholds () const
	Function that returns the values of the thresholds.
int	GetNumberOfSteps () const
	Function that returns the number of steps.
void	SetObjectRef (double ObjRef)
	Function that sets the reference value of the object.
void	SetMuRef (double const &MuRef)
	Function that sets the reference scale.
void	SetNumberOfSteps (int const &nsteps)
	Function that sets the number of steps of the RK algorithm.

Private Attributes
int const	_pt
	Perturbative order.
double const	_kappa
	Resummation-scale parameter.
std::function< double(bool const &, int const &, double const &)>	_MatchingConditions
	Matching condition functions.

Additional Inherited Members
Protected Attributes inherited from apfel::MatchedEvolution< double >
double	_ObjRef
double	_MuRef
double	_MuRef2
double	_LogMuRef2
std::vector< double >	_Thresholds
int	_nsteps
std::vector< double >	_Thresholds2
std::vector< double >	_LogThresholds2

Detailed Description

The AlphaQCDg is a specialization class of the MatchedEvolution class for the computation of the QCD coupling running using the analytic g functions.

Examples

coupling_test.cc.

Constructor & Destructor Documentation

AlphaQCDg() [1/3]

apfel::AlphaQCDg::AlphaQCDg ( )

delete

AlphaQCDg() [2/3]

apfel::AlphaQCDg::AlphaQCDg	(	double const &	AlphaRef,
		double const &	MuRef,
		std::vector< double > const &	Masses,
		std::vector< double > const &	Thresholds,
		int const &	pt,
		double const &	kappa = 1 )

AlphaQCDg constructor.

Parameters

AlphaRef	the reference value of the coupling
MuRef	the reference value of the scale
Masses	vector of masses
Thresholds	vector of thresholds
pt	perturbative order
kappa	resummation scale parameter (default: 1)

AlphaQCDg() [3/3]

apfel::AlphaQCDg::AlphaQCDg	(	double const &	AlphaRef,
		double const &	MuRef,
		std::vector< double > const &	Masses,
		int const &	pt,
		double const &	kappa = 1 )

AlphaQCDg constructor.

Parameters

AlphaRef	the reference value of the coupling
MuRef	the reference value of the scale
Masses	vector of masses
pt	perturbative order
kappa	resummation scale parameter (default: 1)

Note

This constructor assumes that masses and thresholds coincide.

Member Function Documentation

Derivative()

double apfel::AlphaQCDg::Derivative ( int const & , double const & , double const &  ) const

inlinevirtual

Dummy function used to overload a purely virtual function. It should be never called.

Implements apfel::MatchedEvolution< double >.

EvolveObject()

double apfel::AlphaQCDg::EvolveObject ( int const & nf, double const & lnmu02, double const & lnmu2, double const & as0 ) const

virtual

Function for the computation of the evolution.

Parameters

nf	the number of active flavours
lnmu02	the log of the initial value of the scale
lnmu2	the log of the final value of the scale
as0	the starting object

Returns

the object evolved at the scale mu2

Reimplemented from apfel::MatchedEvolution< double >.

MatchObject()

double apfel::AlphaQCDg::MatchObject ( bool const & Up, int const & nf, double const & Coup ) const

virtual

Function for the computation of the matching.

Parameters

Up	tells whether the matching is upward or not (downward)
nf	number of active flavours
Coup	value of the coupling to be matched

Returns

The matched value of the strong coupling at the threshold

Implements apfel::MatchedEvolution< double >.

Member Data Documentation

_kappa

double const apfel::AlphaQCDg::_kappa

private

Resummation-scale parameter.

_MatchingConditions

std::function<double(bool const&, int const&, double const&)> apfel::AlphaQCDg::_MatchingConditions

private

Matching condition functions.

_pt

int const apfel::AlphaQCDg::_pt

private

Perturbative order.

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

• /Users/vb262523/Codes/apfelxx/inc/apfel/alphaqcdg.h