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ThePEG  2.1.5
ThePEG::O1AlphaS Class Reference

O1AlphaS inherits from AlphaSBase and implements the leading order running QCD coupling. More...

#include <O1AlphaS.h>

Inheritance diagram for ThePEG::O1AlphaS:

Public Member Functions

int getMaxFlav () const
 Return the maximum number of active flavours.
 
Standard constructors and destructors.
 O1AlphaS ()
 Default constructor.
 
Virtual functions mandated by the sub-class.
virtual double value (Energy2 scale, const StandardModelBase &) const
 The $\alpha_S$. More...
 
virtual unsigned int nloops () const
 Return the number of loops contributing to the running this coupling.
 
virtual vector< Energy2flavourThresholds () const
 Return the flavour thresholds used. More...
 
virtual vector< EnergyLambdaQCDs () const
 Return the $\Lambda_{QCD}$ used for different numbers of active flavours.
 
Functions used by the persistent I/O system.
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::AlphaSBase
const vector< Energy > & quarkMasses () const
 Return the quark masses to be used; if not empty these masses should be considered instead of the ones set in the particle data objects.
 
unsigned int Nf (Energy2 scale) const
 Return the number of avtive quark flavours.
 
Energy LambdaQCD (unsigned int nflav) const
 Return the $\Lambda_{QCD}$ used for nflav active flavours.
 
Energy LambdaQCD (Energy2 scale) const
 Return the $\Lambda_{QCD}$ used for corresponding given scale.
 
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::RunningCoupling
 RunningCoupling ()
 The default constructor.
 
double value (Energy2 scale) const
 Return the value of the coupling at a given scale using the StandardModelBase object used by the EventGenerator.
 
virtual double overestimateValue (Energy2 scale) const
 Return an overestimate to the running coupling at the given scale. More...
 
virtual double ratioToOverestimate (Energy2) const
 Return the ratio of the exact to the overestimated value of the running coupling. More...
 
double scaleFactor () const
 Return the scale factor, which may be used to globally rescale the argument of the running coupling.
 
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 ~Interfaced ()
 Empty virtual destructor.
 
virtual bool defaultInit ()
 Functions which are to be used during the actual event generation, after the setup is complete. More...
 
PPtr getParticle (PID) const
 Create a new Particle instance given a id number.
 
PDPtr getParticleData (PID) const
 Return a pointer to the ParticleData object corresponding to the given id number.
 
bool used () const
 Returns true if this object has actally been used.
 
void useMe () const
 Should be called to indicate that this object has actually been used.
 
tEGPtr generator () const
 Return a pointer to the EventGenerator controlling the run. 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::InterfacedBase
virtual ~InterfacedBase ()
 The virtual (empty) destructor;.
 
string fullName () const
 Returns the full name of this object including its path, e.g. More...
 
string name () const
 Returns the name of this object, without the path.
 
string path () const
 Returns the path to this object including the trailing '/'. More...
 
string comment () const
 Returns a comment assigned to this object.
 
void setup (istream &is)
 Read setup info from a standard istream is. More...
 
virtual void debugme () const
 Print out debugging information for this object on std::cerr. More...
 
void update ()
 Calls the doupdate() function with recursion prevention.
 
void init ()
 Calls the doinit() function with recursion prevention.
 
virtual bool preInitialize () const
 Return true if this object needs to be initialized before all other objects (except those for which this function also returns true). More...
 
void initrun ()
 Calls the doinitrun() function with recursion prevention.
 
void finish ()
 Calls the dofinish() function with recursion prevention.
 
void touch ()
 This function should be called every time something in this object has changed in a way that a sanity check with update() is needed.
 
void reset ()
 Set the state of this object to uninitialized.
 
void clear ()
 Calls reset() and unTouch().
 
InitState state () const
 Return the state of initialization of this object.
 
bool locked () const
 Return true if the BaseRepository is not allowed to change the state of this object.
 
bool touched () const
 Return true if the state of this object has been changed since the last call to update().
 
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::Base
virtual ~Base ()
 The virtual destructor.
 
void debug () const
 Print out debugging information for this object on std::cerr. More...
 
- Public Member Functions inherited from ThePEG::Pointer::ReferenceCounted
CounterType referenceCount () const
 Return the reference count.
 
- Public Member Functions inherited from ThePEG::Named
 Named (const string &newName=string())
 Constructor with name.
 
 Named (const Named &)=default
 Explicit default copy-constructor (too avoid compiler warnings)
 
const string & name () const
 Return name.
 
bool operator== (const Named &other) const
 Test for equality.
 
bool operator< (const Named &other) const
 Lexicographical comparison.
 

Static Public Member Functions

static void Init ()
 Standard Init function used to initialize the interface.
 
- Static Public Member Functions inherited from ThePEG::AlphaSBase
static void Init ()
 Standard Init function used to initialize the interface.
 
- Static Public Member Functions inherited from ThePEG::RunningCoupling
static void Init ()
 Standard Init function used to initialize the interface.
 
- Static Public Member Functions inherited from ThePEG::Interfaced
static void Init ()
 Standard Init function.
 
- Static Public Member Functions inherited from ThePEG::InterfacedBase
static void Init ()
 Standard Init function.
 
- Static Public Member Functions inherited from ThePEG::Base
static void Init ()
 The standard Init function used to initialize the interfaces. More...
 

Protected Member Functions

Clone Methods.
virtual IBPtr clone () const
 Make a simple clone of this object. More...
 
virtual IBPtr fullclone () const
 Make a clone of this object, possibly modifying the cloned object to make it sane. More...
 
- Protected Member Functions inherited from ThePEG::AlphaSBase
virtual void doinit ()
 Initialize this object after the setup phase before saving an EventGenerator to disk. More...
 
- Protected Member Functions inherited from ThePEG::Interfaced
void reporeg (IBPtr object, string name) const
 Register the given object in the Repository with the given name in a subdirectory with the same name as this object. More...
 
template<typename PtrT >
bool setDefaultReference (PtrT &ptr, string classname, string objectname)
 If the pointer, ptr, to an object is not set, create an object of class classname and register it with the Repository with the given objectname in a sib-directory with the same name as this object.
 
 Interfaced ()
 Protected default constructor.
 
 Interfaced (const string &newName)
 Protected constructor taking a name as argument.
 
 Interfaced (const Interfaced &i)
 Protected copy-constructor.
 
void setGenerator (tEGPtr generator)
 Protected function to reset the generator pointer, required for automatic decayer generation in Herwig++ BSM models.
 
- Protected Member Functions inherited from ThePEG::InterfacedBase
 InterfacedBase ()
 Protected default constructor.
 
 InterfacedBase (string newName)
 Protected constructor with the name given as argument.
 
 InterfacedBase (const InterfacedBase &i)
 Protected copy-constructor.
 
virtual void readSetup (istream &is)
 Read setup info from a standard istream is. More...
 
virtual void doupdate ()
 Check sanity of the object during the setup phase. More...
 
virtual void doinitrun ()
 Initialize this object. More...
 
virtual void dofinish ()
 Finalize this object. More...
 
virtual IVector getReferences ()
 Return a vector of all pointers to Interfaced objects used in this object. More...
 
virtual void rebind (const TranslationMap &)
 Rebind pointer to other Interfaced objects. More...
 
- Protected Member Functions inherited from ThePEG::Pointer::ReferenceCounted
 ReferenceCounted ()
 Default constructor.
 
 ReferenceCounted (const ReferenceCounted &)
 Copy-constructor.
 
ReferenceCountedoperator= (const ReferenceCounted &)
 Assignment.
 
- Protected Member Functions inherited from ThePEG::Named
const Namedoperator= (const Named &other)
 Assignment.
 
const string & name (const string &newName)
 Set new name.
 

Private Member Functions

O1AlphaSoperator= (const O1AlphaS &)=delete
 Private and non-existent assignment operator.
 

Private Attributes

Energy theLambdaQCD
 The $\Lambda_{QCD}$ for the number of flavours specified by theLambdaFlavour. More...
 
int theLambdaFlavour
 The number of flavours for which theLambdaQCD is given.
 
int theMaxFlav
 The maximum number of active flavours.
 
Energy Q0
 The scale below which $\alpha_S$ is frozen.
 

Static Private Attributes

static ClassDescription< O1AlphaSinitO1AlphaS
 Describe a concrete class with persistent data.
 

Additional Inherited Members

- Public Types inherited from ThePEG::InterfacedBase
enum  InitState { initializing = -1, uninitialized = 0, initialized = 1, runready = 2 }
 Enumeration reflecting the state of an InterfacedBase object. More...
 
- Public Types inherited from ThePEG::Pointer::ReferenceCounted
typedef unsigned int CounterType
 The integer type used for counting.
 
- Public Attributes inherited from ThePEG::Pointer::ReferenceCounted
const unsigned long uniqueId
 The unique ID. More...
 
- Static Protected Member Functions inherited from ThePEG::Interfaced
static void registerRepository (IBPtr)
 Register an Interfaced object with the Repository.
 
static void registerRepository (IBPtr, string newName)
 Register an Interfaced object with the Repository, giving it a name.
 

Detailed Description

O1AlphaS inherits from AlphaSBase and implements the leading order running QCD coupling.

The value is determined by a $\Lambda_{QCD}$ parameter at a given number of flavours. Optionally the coupling can be frozen under some minimum scale to avoid divergencies or negative couplings.

See also
The interfaces defined for O1AlphaS.

Definition at line 27 of file O1AlphaS.h.

Member Function Documentation

◆ clone()

virtual IBPtr ThePEG::O1AlphaS::clone ( ) const
protectedvirtual

Make a simple clone of this object.

Returns
a pointer to the new object.

Implements ThePEG::InterfacedBase.

Referenced by getMaxFlav().

◆ flavourThresholds()

virtual vector<Energy2> ThePEG::O1AlphaS::flavourThresholds ( ) const
virtual

Return the flavour thresholds used.

The returned vector contains (in position i) the scales when the active number of flavours changes from i to i+1.

Implements ThePEG::AlphaSBase.

Referenced by nloops().

◆ fullclone()

virtual IBPtr ThePEG::O1AlphaS::fullclone ( ) const
protectedvirtual

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

Returns
a pointer to the new object.

Reimplemented from ThePEG::InterfacedBase.

Referenced by getMaxFlav().

◆ persistentInput()

void ThePEG::O1AlphaS::persistentInput ( PersistentIStream is,
int  version 
)

Function used to read in object persistently.

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

Referenced by getMaxFlav().

◆ persistentOutput()

void ThePEG::O1AlphaS::persistentOutput ( PersistentOStream os) const

Function used to write out object persistently.

Parameters
osthe persistent output stream written to.

Referenced by getMaxFlav().

◆ value()

virtual double ThePEG::O1AlphaS::value ( Energy2  scale,
const StandardModelBase  
) const
virtual

The $\alpha_S$.

Return the QCD coupling for a given scale using the given standard model object sm.

Implements ThePEG::RunningCoupling.

Referenced by O1AlphaS().

Member Data Documentation

◆ theLambdaQCD

Energy ThePEG::O1AlphaS::theLambdaQCD
private

The $\Lambda_{QCD}$ for the number of flavours specified by theLambdaFlavour.

Other $\Lambda_{QCD}$ values for other numbers of active flavours are calculated from flavourThresholds() using a continuity requirement.

Definition at line 125 of file O1AlphaS.h.


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