APFEL 4.8.0
A PDF evolution library in C++
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Public Member Functions | Private Attributes | List of all members
apfel::AlphaQCDQED Class Reference

The AlphaQCDQED is a specialization class of the MatchedEvolution class for the computation of the mixed evolution of QCD and QED. More...

#include <alphaqcdqed.h>

Inheritance diagram for apfel::AlphaQCDQED:
apfel::MatchedEvolution< matrix< double > >

Public Member Functions

matrix< double > MatchObject (bool const &Up, int const &nfl, matrix< double > const &Coup) const
 Function for the computation of the matching.
 
matrix< double > Derivative (int const &nfl, double const &, matrix< double > const &as) const
 Function that returns QCDxQED $\beta$ function matrix.
 
matrix< double > betaQCDQED (int const &pt, int const &nf, int const &nl) const
 Function for the computation of the single coefficients of the expansion of the QCDxQED $\beta$ function.
 
Constructors

List of constructors.

 AlphaQCDQED ()=delete
 
 AlphaQCDQED (double const &AlphaQCDRef, double const &AlphaQEDRef, double const &MuRef, std::vector< double > const &QuarkThresholds, std::vector< double > const &LeptThresholds, int const &pt, int const &nsteps=10)
 AlphaQCDQED constructor.
 
- Public Member Functions inherited from apfel::MatchedEvolution< matrix< double > >
 MatchedEvolution ()=delete
 
 MatchedEvolution (matrix< double > const &ObjRef, double const &MuRef, std::vector< double > const &Thresholds, int const &nsteps=10)
 The MatchedEvolution constructor.
 
virtual ~MatchedEvolution ()=default
 
virtual matrix< double > EvolveObject (int const &nf, double const &t0, double const &t1, matrix< double > const &Obj0) const
 Virtual function for the computation of the evolution.
 
matrix< double > Evaluate (double const &mu) const
 Function that returns the evolved object.
 
matrix< 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 (matrix< 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.
 
std::function< matrix< double >(int const &, matrix< double > const &) _BetaFunction )
 Beta function.
 

Additional Inherited Members

- Protected Attributes inherited from apfel::MatchedEvolution< matrix< double > >
matrix< 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 AlphaQCDQED is a specialization class of the MatchedEvolution class for the computation of the mixed evolution of QCD and QED.

Examples
coupling_test.cc.

Constructor & Destructor Documentation

◆ AlphaQCDQED() [1/2]

apfel::AlphaQCDQED::AlphaQCDQED ( )
delete

◆ AlphaQCDQED() [2/2]

apfel::AlphaQCDQED::AlphaQCDQED ( double const & AlphaQCDRef,
double const & AlphaQEDRef,
double const & MuRef,
std::vector< double > const & QuarkThresholds,
std::vector< double > const & LeptThresholds,
int const & pt,
int const & nsteps = 10 )

AlphaQCDQED constructor.

Parameters
AlphaQCDRefthe reference value of the QCD coupling
AlphaQEDRefthe reference value of the QED coupling
MuRefthe reference value of the scale
QuarkThresholdsvector of quark thresholds
LeptThresholdsvector of lepton thresholds
ptperturbative order
nstepsnumber of steps of the ODE solver
Note
No displaced thresholds allowed.

Member Function Documentation

◆ betaQCDQED()

matrix< double > apfel::AlphaQCDQED::betaQCDQED ( int const & pt,
int const & nf,
int const & nl ) const

Function for the computation of the single coefficients of the expansion of the QCDxQED $\beta$ function.

Parameters
ptperturbative order
nfnumber of active quark flavours
nlnumber of active lepton flavours
Returns
The pt-th coefficient of the QCDxQED $\beta$ function.

◆ Derivative()

matrix< double > apfel::AlphaQCDQED::Derivative ( int const & nfl,
double const & ,
matrix< double > const & as ) const
virtual

Function that returns QCDxQED $\beta$ function matrix.

Parameters
nfltotal number of active flavours including both quarks and leptons
asvalue of the couplings
Returns
The the value of the QCDxQED $\beta$ function matrix

Implements apfel::MatchedEvolution< matrix< double > >.

◆ MatchObject()

matrix< double > apfel::AlphaQCDQED::MatchObject ( bool const & Up,
int const & nfl,
matrix< double > const & Coup ) const
virtual

Function for the computation of the matching.

Parameters
Uptells whether the matching is upward or not (downward)
nfltotal number of active flavours including both quarks and leptons
Coupvalue of the coupling to be matched
Returns
The matched value of the strong coupling $\alpha_s$ at the threshold
Note
This is a dummy function required only to instantiate the pure-virtual 'MatchObject' of the mother class 'MatchedEvolution': it always returns the input coupling. This means that the evolution is assumed to be continuos at the thresholds.

Implements apfel::MatchedEvolution< matrix< double > >.

Member Data Documentation

◆ _BetaFunction

std::function<matrix<double>(int const&, matrix<double> const&) apfel::AlphaQCDQED::_BetaFunction)
private

Beta function.

◆ _pt

int const apfel::AlphaQCDQED::_pt
private

Perturbative order.


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