#include <UserHooks.h>

Inheritance diagram for SuppressSmallPT:

Public Member Functions
	SuppressSmallPT (double pT0timesMPIIn=1., int numberAlphaSIn=0, bool useSameAlphaSasMPIIn=true)
	Constructor.

virtual bool	canModifySigma ()
	Possibility to modify cross section of process.

virtual double	multiplySigmaBy (const SigmaProcess sigmaProcessPtr, const PhaseSpace phaseSpacePtr, bool)
	The SuppressSmallPT class, derived from UserHooks. More...

Public Member Functions inherited from UserHooks
virtual	~UserHooks ()
	Destructor.

virtual bool	initAfterBeams ()
	Initialisation after beams have been set by Pythia::init().

virtual bool	canBiasSelection ()
	Possibility to bias selection of events, compensated by a weight.

virtual double	biasSelectionBy (const SigmaProcess sigmaProcessPtr, const PhaseSpace phaseSpacePtr, bool inEvent)
	Multiplicative factor in the phase space selection of a hard process. More...

virtual double	biasedSelectionWeight ()
	Event weight to compensate for selection weight above.

virtual bool	canVetoProcessLevel ()
	Possibility to veto event after process-level selection.

virtual bool	doVetoProcessLevel (Event &)

virtual bool	canSetLowEnergySigma (int, int) const

virtual double	doSetLowEnergySigma (int, int, double, double, double) const

virtual bool	canVetoResonanceDecays ()
	Possibility to veto resonance decay chain.

virtual bool	doVetoResonanceDecays (Event &)

virtual bool	canVetoPT ()

virtual double	scaleVetoPT ()
	Transverse-momentum scale for veto test.

virtual bool	doVetoPT (int, const Event &)

virtual bool	canVetoStep ()

virtual int	numberVetoStep ()
	Up to how many ISR + FSR steps of hardest interaction should be checked.

virtual bool	doVetoStep (int, int, int, const Event &)

virtual bool	canVetoMPIStep ()

virtual int	numberVetoMPIStep ()
	Up to how many MPI steps should be checked.

virtual bool	doVetoMPIStep (int, const Event &)

virtual bool	canVetoPartonLevelEarly ()

virtual bool	doVetoPartonLevelEarly (const Event &)

virtual bool	retryPartonLevel ()

virtual bool	canVetoPartonLevel ()
	Possibility to veto event after parton-level selection.

virtual bool	doVetoPartonLevel (const Event &)

virtual bool	canSetResonanceScale ()
	Possibility to set initial scale in TimeShower for resonance decay.

virtual double	scaleResonance (int, const Event &)

virtual bool	canVetoISREmission ()
	Possibility to veto an emission in the ISR machinery.

virtual bool	doVetoISREmission (int, const Event &, int)

virtual bool	canVetoFSREmission ()
	Possibility to veto an emission in the FSR machinery.

virtual bool	doVetoFSREmission (int, const Event &, int, bool=false)

virtual bool	canVetoMPIEmission ()
	Possibility to veto an MPI.

virtual bool	doVetoMPIEmission (int, const Event &)

virtual bool	canReconnectResonanceSystems ()
	Possibility to reconnect colours from resonance decay systems.

virtual bool	doReconnectResonanceSystems (int, Event &)

virtual bool	canChangeFragPar ()
	Can change fragmentation parameters.

virtual void	setStringEnds (const StringEnd , const StringEnd , vector< int >)

virtual bool	doChangeFragPar (StringFlav , StringZ , StringPT , int, double, vector< int >, const StringEnd )

virtual bool	doVetoFragmentation (Particle, const StringEnd *)

virtual bool	doVetoFragmentation (Particle, Particle, const StringEnd , const StringEnd )

virtual bool	canVetoAfterHadronization ()

virtual bool	doVetoAfterHadronization (const Event &)
	Do the actual veto after hadronization.

virtual bool	canSetImpactParameter () const
	Can set the overall impact parameter for the MPI treatment.

virtual double	doSetImpactParameter ()
	Set the overall impact parameter for the MPI treatment.

virtual bool	onEndHadronLevel (HadronLevel &, Event &)
	Custom processing at the end of HadronLevel::next.

Public Member Functions inherited from PhysicsBase
void	initInfoPtr (Info &infoPtrIn)
	This function is called from above for physics objects used in a run. More...

virtual	~PhysicsBase ()
	Empty virtual destructor.

bool	flag (string key) const
	Shorthand to read settings values.

int	mode (string key) const

double	parm (string key) const

string	word (string key) const

vector< bool >	fvec (string key) const

vector< int >	mvec (string key) const

vector< double >	pvec (string key) const

vector< string >	wvec (string key) const

Additional Inherited Members
Public Types inherited from PhysicsBase
enum	Status { INCOMPLETE = -1, COMPLETE = 0, CONSTRUCTOR_FAILED, INIT_FAILED, LHEF_END, LOWENERGY_FAILED, PROCESSLEVEL_FAILED, PROCESSLEVEL_USERVETO, MERGING_FAILED, PARTONLEVEL_FAILED, PARTONLEVEL_USERVETO, HADRONLEVEL_FAILED, CHECK_FAILED, OTHER_UNPHYSICAL, HEAVYION_FAILED, HADRONLEVEL_USERVETO }
	Enumerate the different status codes the event generation can have.

Protected Member Functions inherited from UserHooks
	UserHooks ()
	Constructor.

virtual void	onInitInfoPtr () override
	After initInfoPtr, initialize workEvent. More...

void	omitResonanceDecays (const Event &process, bool finalOnly=false)
	omitResonanceDecays omits resonance decay chains from process record. More...

void	subEvent (const Event &event, bool isHardest=true)
	subEvent extracts currently resolved partons in the hard process. More...

Protected Member Functions inherited from PhysicsBase
	PhysicsBase ()
	Default constructor.

virtual void	onBeginEvent ()
	This function is called in the very beginning of each Pythia::next call.

virtual void	onEndEvent (Status)

virtual void	onStat ()
	This function is called from the Pythia::stat() call.

void	registerSubObject (PhysicsBase &pb)
	Register a sub object that should have its information in sync with this.

Protected Attributes inherited from UserHooks
Event	workEvent = {}
	Have one event object around as work area.

double	selBias = 1.
	User-imposed selection bias.

double	enhancedEventWeight = {}
	Bookkept quantities for boosted event weights.

double	pTEnhanced = {}

double	wtEnhanced = {}

Protected Attributes inherited from PhysicsBase
Info *	infoPtr = {}

Settings *	settingsPtr = {}
	Pointer to the settings database.

ParticleData *	particleDataPtr = {}
	Pointer to the particle data table.

Logger *	loggerPtr = {}
	Pointer to logger.

HadronWidths *	hadronWidthsPtr = {}
	Pointer to the hadron widths data table.

Rndm *	rndmPtr = {}
	Pointer to the random number generator.

CoupSM *	coupSMPtr = {}
	Pointers to SM and SUSY couplings.

CoupSUSY *	coupSUSYPtr = {}

BeamSetup *	beamSetupPtr = {}

BeamParticle *	beamAPtr = {}

BeamParticle *	beamBPtr = {}

BeamParticle *	beamPomAPtr = {}

BeamParticle *	beamPomBPtr = {}

BeamParticle *	beamGamAPtr = {}

BeamParticle *	beamGamBPtr = {}

BeamParticle *	beamVMDAPtr = {}

BeamParticle *	beamVMDBPtr = {}

PartonSystems *	partonSystemsPtr = {}
	Pointer to information on subcollision parton locations.

SigmaTotal *	sigmaTotPtr = {}
	Pointers to the total/elastic/diffractive cross sections.

SigmaCombined *	sigmaCmbPtr = {}

set< PhysicsBase * >	subObjects

UserHooksPtr	userHooksPtr

Detailed Description

SuppressSmallPT is a derived class for user access to program execution. It is a simple example, illustrating how to suppress the cross section of 2 -> 2 processes by a factor pT^4 / (pT0^2 + pT^2)^2, with pT0 input, and also modify alpha_strong scale similarly.

Member Function Documentation

double multiplySigmaBy	(	const SigmaProcess *	sigmaProcessPtr,
		const PhaseSpace *	phaseSpacePtr,
		bool
	)

virtual

The SuppressSmallPT class, derived from UserHooks.

Multiplicative factor modifying the cross section of a hard process. Usage: inEvent is true for event generation, false for initialization.

Modify event weight at the trial level, before selection.

Need to initialize first time this method is called.

Calculate pT0 as for multiparton interactions. Fudge factor allows offset relative to MPI framework.

Initialize alpha_strong object as for multiparton interactions, alternatively as for hard processes.

Initialization finished.

Only modify 2 -> 2 processes.

pT scale of process. Weight pT^4 / (pT^2 + pT0^2)^2

Renormalization scale and assumed alpha_strong.

Reweight to new alpha_strong at new scale.

End weight calculation.

Reimplemented from UserHooks.

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

include/Pythia8/UserHooks.h
src/UserHooks.cc

Public Member Functions

Additional Inherited Members

Detailed Description

Member Function Documentation