Par02Smearer Class Reference

Smearing of the particle momentum or energy. More...

#include <Doxymodules_parameterisations.h>

Public Member Functions
G4ThreeVector	SmearMomentum (const G4Track *aTrack, G4double aResolution=-1)
	Smears the momentum with a given resolution.
G4double	SmearEnergy (const G4Track *aTrack, G4double aResolution=-1)
	Smears the energy deposit with a given resolution.
G4ThreeVector	SmearGaussian (const G4Track *aTrackOriginal, G4double aResolution)
	First possible type of smearing.
G4double	Gauss (G4double aMean, G4double aStandardDeviation)
	Returns a random number from a Gaussian distribution.

Static Public Member Functions
static Par02Smearer *	Instance ()
	Allows the access to the unique Par02Smearer class object.

Protected Member Functions
	Par02Smearer ()
	A default constructor.
	~Par02Smearer ()

Private Attributes
CLHEP::HepRandomEngine *	fRandomEngine
	CLHEP random engine.
CLHEP::RandGauss *	fRandomGauss
	CLHEP random engine used in gaussian smearing.

Static Private Attributes
static Par02Smearer *	fPar02Smearer = nullptr
	A pointer to Par02Smearer object.

Detailed Description

Smearing of the particle momentum or energy.

A singleton class used to smear (alter) the particle momentum (for tracking detectors) and energy (for calorimeters). In case the resolution is given, the momentum (energy) is smeared with Gaussian distribution.

Author

Anna Zaborowska

Definition at line 49 of file Doxymodules_parameterisations.h.

Constructor & Destructor Documentation

Par02Smearer()

Par02Smearer::Par02Smearer ( )

protected

A default constructor.

Definition at line 46 of file Par02Smearer.cc.

                           {
  time_t seed = time( NULL );
  fRandomEngine = new CLHEP::HepJamesRandom( static_cast< long >( seed ) );
  fRandomGauss = new CLHEP::RandGauss( fRandomEngine );
}

~Par02Smearer()

Par02Smearer::~Par02Smearer ( )

protecteddefault

Member Function Documentation

Instance()

Par02Smearer * Par02Smearer::Instance ( )

static

Allows the access to the unique Par02Smearer class object.

Returns

A pointer to the Par02Smearer class.

Definition at line 58 of file Par02Smearer.cc.

                                     {
  if ( ! fPar02Smearer ) {
    fPar02Smearer = new Par02Smearer();
  }
  return fPar02Smearer;
}

SmearMomentum()

G4ThreeVector Par02Smearer::SmearMomentum	(	const G4Track *	aTrack,
		G4double	aResolution = -1
	)

Smears the momentum with a given resolution.

Parameters

aTrack	A track to smear.
aResolution	A resolution. Gaussian smearing is done with a given resolution as a standard deviation.

Definition at line 67 of file Par02Smearer.cc.

                                                                  {
  return SmearGaussian( aTrackOriginal, aResolution );
}

SmearEnergy()

G4double Par02Smearer::SmearEnergy	(	const G4Track *	aTrack,
		G4double	aResolution = -1
	)

Smears the energy deposit with a given resolution.

Parameters

aTrack	A track to smear.
aResolution	A resolution. Gaussian smearing is done with a given resolution as a standard deviation.

Definition at line 74 of file Par02Smearer.cc.

                                                           {
  G4double newE = -1.0;
  while ( newE < 0.0 ) {  // To ensure that the resulting value is not negative
                          // (vital for energy smearing, does not change direction
                          // for momentum smearing)
    if ( aResolution != -1.0 ) {
      newE = aTrackOriginal->GetKineticEnergy() * Gauss( 1.0, aResolution );
    } else {
      newE = aTrackOriginal->GetKineticEnergy();
    }
  }
  return newE;
}

SmearGaussian()

G4ThreeVector Par02Smearer::SmearGaussian	(	const G4Track *	aTrackOriginal,
		G4double	aResolution
	)

First possible type of smearing.

Smears the momentum with a given resolution.

Parameters

aTrackOriginal	A track to smear.
aResolution	A resolution taken as a standard deviation of a Gaussian distribution.

Definition at line 91 of file Par02Smearer.cc.

                                                                  {
  G4ThreeVector originP = aTrackOriginal->GetMomentum();
  G4ThreeVector originPos = aTrackOriginal->GetPosition();
  G4double rdm = Gauss( 1.0, aResolution );
  G4ThreeVector smearedMom( originP.x()*rdm, originP.y()*rdm, originP.z()*rdm );
  return smearedMom;
}

Gauss()

G4double Par02Smearer::Gauss	(	G4double	aMean,
		G4double	aStandardDeviation
	)

Returns a random number from a Gaussian distribution.

Parameters

aMean	The mean of the Gaussian distribution.
aStandardDeviation	The standard deviation of a Gaussian distribution.

Definition at line 102 of file Par02Smearer.cc.

                                                                          {
  return fRandomGauss->fire( aMean, aStandardDeviation );
}

Member Data Documentation

fPar02Smearer

Par02Smearer * Par02Smearer::fPar02Smearer = nullptr

staticprivate

A pointer to Par02Smearer object.

Definition at line 86 of file Par02Smearer.hh.

fRandomEngine

CLHEP::HepRandomEngine* Par02Smearer::fRandomEngine

private

CLHEP random engine.

Definition at line 89 of file Par02Smearer.hh.

fRandomGauss

CLHEP::RandGauss* Par02Smearer::fRandomGauss

private

CLHEP random engine used in gaussian smearing.

Definition at line 92 of file Par02Smearer.hh.

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

• .doxygen/Doxymodules_parameterisations.h
• extended/parameterisations/Par02/include/Par02Smearer.hh
• extended/parameterisations/Par02/src/Par02Smearer.cc