#include <G4KL3DecayChannel.hh>

Inheritance diagram for G4KL3DecayChannel:

Public Member Functions
	G4KL3DecayChannel (const G4String &theParentName, G4double theBR, const G4String &thePionName, const G4String &theLeptonName, const G4String &theNutrinoName)

	~G4KL3DecayChannel () override=default

G4DecayProducts *	DecayIt (G4double) override

void	SetDalitzParameter (G4double aLambda, G4double aXi)

G4double	GetDalitzParameterLambda () const

G4double	GetDalitzParameterXi () const

Public Member Functions inherited from G4VDecayChannel
	G4VDecayChannel (const G4String &aName, G4int Verbose=1)

	G4VDecayChannel (const G4String &aName, const G4String &theParentName, G4double theBR, G4int theNumberOfDaughters, const G4String &theDaughterName1, const G4String &theDaughterName2="", const G4String &theDaughterName3="", const G4String &theDaughterName4="", const G4String &theDaughterName5="")

virtual	~G4VDecayChannel ()

G4bool	operator== (const G4VDecayChannel &r) const

G4bool	operator!= (const G4VDecayChannel &r) const

G4bool	operator< (const G4VDecayChannel &right) const

const G4String &	GetKinematicsName () const

G4double	GetBR () const

G4int	GetNumberOfDaughters () const

G4ParticleDefinition *	GetParent ()

G4ParticleDefinition *	GetDaughter (G4int anIndex)

G4int	GetAngularMomentum ()

const G4String &	GetParentName () const

const G4String &	GetDaughterName (G4int anIndex) const

G4double	GetParentMass () const

G4double	GetDaughterMass (G4int anIndex) const

void	SetParent (const G4ParticleDefinition *particle_type)

void	SetParent (const G4String &particle_name)

void	SetBR (G4double value)

void	SetNumberOfDaughters (G4int value)

void	SetDaughter (G4int anIndex, const G4ParticleDefinition *particle_type)

void	SetDaughter (G4int anIndex, const G4String &particle_name)

void	SetVerboseLevel (G4int value)

G4int	GetVerboseLevel () const

void	DumpInfo ()

G4double	GetRangeMass () const

void	SetRangeMass (G4double val)

virtual G4bool	IsOKWithParentMass (G4double parentMass)

void	SetPolarization (const G4ThreeVector &)

const G4ThreeVector &	GetPolarization () const

Protected Types
enum	{ idPi = 0 , idLepton = 1 , idNutrino = 2 }

Protected Member Functions
	G4KL3DecayChannel (const G4KL3DecayChannel &)=default

G4KL3DecayChannel &	operator= (const G4KL3DecayChannel &)

void	PhaseSpace (G4double Mparent, const G4double Mdaughter, G4double Edaughter, G4double *Pdaughter)

G4double	DalitzDensity (G4double parentmass, G4double Epi, G4double El, G4double Enu, G4double massPi, G4double massL, G4double massNu)

Protected Member Functions inherited from G4VDecayChannel
	G4VDecayChannel ()

	G4VDecayChannel (const G4VDecayChannel &)

G4VDecayChannel &	operator= (const G4VDecayChannel &)

void	ClearDaughtersName ()

void	CheckAndFillDaughters ()

void	CheckAndFillParent ()

G4double	DynamicalMass (G4double massPDG, G4double width, G4double maxDev=1.0) const

Additional Inherited Members
Protected Attributes inherited from G4VDecayChannel
G4String	kinematics_name = ""

G4double	rbranch = 0.0

G4String *	parent_name = nullptr

G4String **	daughters_name = nullptr

G4double	rangeMass = 2.5

G4ThreeVector	parent_polarization

G4ParticleTable *	particletable = nullptr

G4ParticleDefinition *	G4MT_parent = nullptr

G4ParticleDefinition **	G4MT_daughters = nullptr

G4double	G4MT_parent_mass = 0.0

G4double *	G4MT_daughters_mass = nullptr

G4double *	G4MT_daughters_width = nullptr

G4Mutex	daughtersMutex

G4Mutex	parentMutex

G4int	numberOfDaughters = 0

G4int	verboseLevel = 1

Static Protected Attributes inherited from G4VDecayChannel
static const G4String	noName = " "

Detailed Description

Definition at line 37 of file G4KL3DecayChannel.hh.

Member Enumeration Documentation

◆ anonymous enum

anonymous enum

protected

Enumerator
idPi
idLepton
idNutrino

Definition at line 57 of file G4KL3DecayChannel.hh.

    {
      idPi = 0,
      idLepton = 1,
      idNutrino = 2
    };

Constructor & Destructor Documentation

◆ G4KL3DecayChannel() [1/2]

G4KL3DecayChannel::G4KL3DecayChannel	(	const G4String &	theParentName,
		G4double	theBR,
		const G4String &	thePionName,
		const G4String &	theLeptonName,
		const G4String &	theNutrinoName )

Definition at line 42 of file G4KL3DecayChannel.cc.

  : G4VDecayChannel("KL3 Decay", theParentName, theBR, 3, thePionName, theLeptonName,
                    theNutrinoName)
{
  static const G4String K_plus("kaon+");
  static const G4String K_minus("kaon-");
  static const G4String K_L("kaon0L");
  static const G4String Mu_plus("mu+");
  static const G4String Mu_minus("mu-");
  static const G4String E_plus("e+");
  static const G4String E_minus("e-");
 
  // check modes
  if (((theParentName == K_plus) && (theLeptonName == E_plus))
      || ((theParentName == K_minus) && (theLeptonName == E_minus)))
  {
    // K+- (Ke3)
    pLambda = 0.0286;
    pXi0 = -0.35;
  }
  else if (((theParentName == K_plus) && (theLeptonName == Mu_plus))
           || ((theParentName == K_minus) && (theLeptonName == Mu_minus)))
  {
    // K+- (Kmu3)
    pLambda = 0.033;
    pXi0 = -0.35;
  }
  else if ((theParentName == K_L) && ((theLeptonName == E_plus) || (theLeptonName == E_minus))) {
    // K0L (Ke3)
    pLambda = 0.0300;
    pXi0 = -0.11;
  }
  else if ((theParentName == K_L) && ((theLeptonName == Mu_plus) || (theLeptonName == Mu_minus))) {
    // K0L (Kmu3)
    pLambda = 0.034;
    pXi0 = -0.11;
  }
  else {
#ifdef G4VERBOSE
    if (GetVerboseLevel() > 2) {
      G4cout << "G4KL3DecayChannel:: constructor :";
      G4cout << "illegal arguments " << G4endl;
      ;
      DumpInfo();
    }
#endif
    // set values for K0L (Ke3) temporarily
    pLambda = 0.0300;
    pXi0 = -0.11;
  }
}

Referenced by G4KL3DecayChannel().

◆ ~G4KL3DecayChannel()

G4KL3DecayChannel::~G4KL3DecayChannel ( )

overridedefault

◆ G4KL3DecayChannel() [2/2]

G4KL3DecayChannel::G4KL3DecayChannel ( const G4KL3DecayChannel & )

protecteddefault

Member Function Documentation

◆ DalitzDensity()

G4double G4KL3DecayChannel::DalitzDensity	(	G4double	parentmass,
		G4double	Epi,
		G4double	El,
		G4double	Enu,
		G4double	massPi,
		G4double	massL,
		G4double	massNu )

protected

Definition at line 287 of file G4KL3DecayChannel.cc.

{
  // KL3 decay - Dalitz Plot Density, see Chounet et al Phys. Rep. 4, 201
  //  Arguments
  //    Epi: kinetic enregy of pion
  //    El:  kinetic enregy of lepton (e or mu)
  //    Enu: kinetic energy of nutrino
  //  Constants
  //    pLambda : linear energy dependence of f+
  //    pXi0    : = f+(0)/f-
  //    pNorm   : normalization factor
  //  Variables
  //    Epi: total energy of pion
  //    El:  total energy of lepton (e or mu)
  //    Enu: total energy of nutrino
 
  // calculate total energy
  Epi = Epi + massPi;
  El = El + massL;
  Enu = Enu + massNu;
 
  G4double Epi_max = (massK * massK + massPi * massPi - massL * massL) / 2.0 / massK;
  G4double E = Epi_max - Epi;
  G4double q2 = massK * massK + massPi * massPi - 2.0 * massK * Epi;
 
  G4double F = 1.0 + pLambda * q2 / massPi / massPi;
  G4double Fmax = 1.0;
  if (pLambda > 0.0) Fmax = (1.0 + pLambda * (massK * massK / massPi / massPi + 1.0));
 
  G4double Xi = pXi0 * (1.0 + pLambda * q2 / massPi / massPi);
 
  G4double coeffA = massK * (2.0 * El * Enu - massK * E) + massL * massL * (E / 4.0 - Enu);
  G4double coeffB = massL * massL * (Enu - E / 2.0);
  G4double coeffC = massL * massL * E / 4.0;
 
  G4double RhoMax = (Fmax * Fmax) * (massK * massK * massK / 8.0);
 
  G4double Rho = (F * F) * (coeffA + coeffB * Xi + coeffC * Xi * Xi);
 
#ifdef G4VERBOSE
  if (GetVerboseLevel() > 2) {
    G4cout << "G4KL3DecayChannel::DalitzDensity  " << G4endl;
    G4cout << " Pi[" << massPi / GeV << "GeV/c/c] :" << Epi / GeV << "GeV" << G4endl;
    G4cout << " L[" << massL / GeV << "GeV/c/c] :" << El / GeV << "GeV" << G4endl;
    G4cout << " Nu[" << massNu / GeV << "GeV/c/c] :" << Enu / GeV << "GeV" << G4endl;
    G4cout << " F :" << F << " Fmax :" << Fmax << "  Xi :" << Xi << G4endl;
    G4cout << " A :" << coeffA << "  B :" << coeffB << "  C :" << coeffC << G4endl;
    G4cout << " Rho :" << Rho << "   RhoMax :" << RhoMax << G4endl;
  }
#endif
  return (Rho / RhoMax);
}

Referenced by DecayIt().

◆ DecayIt()

G4DecayProducts * G4KL3DecayChannel::DecayIt ( G4double )

overridevirtual

Implements G4VDecayChannel.

Definition at line 125 of file G4KL3DecayChannel.cc.

{
  // this version neglects muon polarization
  //              assumes the pure V-A coupling
  //              gives incorrect energy spectrum for Neutrinos
#ifdef G4VERBOSE
  if (GetVerboseLevel() > 1) G4cout << "G4KL3DecayChannel::DecayIt " << G4endl;
#endif
 
  // fill parent particle and its mass
  CheckAndFillParent();
  G4double massK = G4MT_parent->GetPDGMass();
 
  // fill daughter particles and their mass
  CheckAndFillDaughters();
  G4double daughterM[3];
  daughterM[idPi] = G4MT_daughters[idPi]->GetPDGMass();
  daughterM[idLepton] = G4MT_daughters[idLepton]->GetPDGMass();
  daughterM[idNutrino] = G4MT_daughters[idNutrino]->GetPDGMass();
 
  // determine momentum/energy of daughters according to DalitzDensity
  G4double daughterP[3], daughterE[3];
  G4double w;
  G4double r;
  const size_t MAX_LOOP = 10000;
  for (std::size_t loop_counter = 0; loop_counter < MAX_LOOP; ++loop_counter) {
    r = G4UniformRand();
    PhaseSpace(massK, &daughterM[0], &daughterE[0], &daughterP[0]);
    w = DalitzDensity(massK, daughterE[idPi], daughterE[idLepton], daughterE[idNutrino],
                      daughterM[idPi], daughterM[idLepton], daughterM[idNutrino]);
    if (r <= w) break;
  }
 
  // output message
#ifdef G4VERBOSE
  if (GetVerboseLevel() > 1) {
    G4cout << *daughters_name[0] << ":" << daughterP[0] / GeV << "[GeV/c]" << G4endl;
    G4cout << *daughters_name[1] << ":" << daughterP[1] / GeV << "[GeV/c]" << G4endl;
    G4cout << *daughters_name[2] << ":" << daughterP[2] / GeV << "[GeV/c]" << G4endl;
  }
#endif
 
  // create parent G4DynamicParticle at rest
  auto direction = new G4ThreeVector(1.0, 0.0, 0.0);
  auto parentparticle = new G4DynamicParticle(G4MT_parent, *direction, 0.0);
  delete direction;
 
  // create G4Decayproducts
  auto products = new G4DecayProducts(*parentparticle);
  delete parentparticle;
 
  // create daughter G4DynamicParticle
  G4double costheta, sintheta, phi, sinphi, cosphi;
  G4double costhetan, sinthetan, phin, sinphin, cosphin;
 
  // pion
  costheta = 2. * G4UniformRand() - 1.0;
  sintheta = std::sqrt((1.0 - costheta) * (1.0 + costheta));
  phi = twopi * G4UniformRand() * rad;
  sinphi = std::sin(phi);
  cosphi = std::cos(phi);
  direction = new G4ThreeVector(sintheta * cosphi, sintheta * sinphi, costheta);
  G4ThreeVector momentum0 = (*direction) * daughterP[0];
  auto daughterparticle = new G4DynamicParticle(G4MT_daughters[0], momentum0);
  products->PushProducts(daughterparticle);
 
  // neutrino
  costhetan =
    (daughterP[1] * daughterP[1] - daughterP[2] * daughterP[2] - daughterP[0] * daughterP[0])
    / (2.0 * daughterP[2] * daughterP[0]);
  sinthetan = std::sqrt((1.0 - costhetan) * (1.0 + costhetan));
  phin = twopi * G4UniformRand() * rad;
  sinphin = std::sin(phin);
  cosphin = std::cos(phin);
  direction->setX(sinthetan * cosphin * costheta * cosphi - sinthetan * sinphin * sinphi
                  + costhetan * sintheta * cosphi);
  direction->setY(sinthetan * cosphin * costheta * sinphi + sinthetan * sinphin * cosphi
                  + costhetan * sintheta * sinphi);
  direction->setZ(-sinthetan * cosphin * sintheta + costhetan * costheta);
 
  G4ThreeVector momentum2 = (*direction) * daughterP[2];
  daughterparticle = new G4DynamicParticle(G4MT_daughters[2], momentum2);
  products->PushProducts(daughterparticle);
 
  // lepton
  G4ThreeVector momentum1 = (momentum0 + momentum2) * (-1.0);
  daughterparticle = new G4DynamicParticle(G4MT_daughters[1], momentum1);
  products->PushProducts(daughterparticle);
 
#ifdef G4VERBOSE
  if (GetVerboseLevel() > 1) {
    G4cout << "G4KL3DecayChannel::DecayIt ";
    G4cout << "  create decay products in rest frame " << G4endl;
    G4cout << "  decay products address=" << products << G4endl;
    products->DumpInfo();
  }
#endif
  delete direction;
  return products;
}

◆ GetDalitzParameterLambda()

G4double G4KL3DecayChannel::GetDalitzParameterLambda ( ) const

inline

Definition at line 100 of file G4KL3DecayChannel.hh.

{
  return pLambda;
}

◆ GetDalitzParameterXi()

G4double G4KL3DecayChannel::GetDalitzParameterXi ( ) const

inline

Definition at line 105 of file G4KL3DecayChannel.hh.

{
  return pXi0;
}

◆ operator=()

G4KL3DecayChannel & G4KL3DecayChannel::operator= ( const G4KL3DecayChannel & right )

protected

Definition at line 96 of file G4KL3DecayChannel.cc.

{
  if (this != &right) {
    kinematics_name = right.kinematics_name;
    verboseLevel = right.verboseLevel;
    rbranch = right.rbranch;
 
    // copy parent name
    parent_name = new G4String(*right.parent_name);
 
    // clear daughters_name array
    ClearDaughtersName();
 
    // recreate array
    numberOfDaughters = right.numberOfDaughters;
    if (numberOfDaughters > 0) {
      if (daughters_name != nullptr) ClearDaughtersName();
      daughters_name = new G4String*[numberOfDaughters];
      // copy daughters name
      for (G4int index = 0; index < numberOfDaughters; ++index) {
        daughters_name[index] = new G4String(*right.daughters_name[index]);
      }
    }
    pLambda = right.pLambda;
    pXi0 = right.pXi0;
  }
  return *this;
}

◆ PhaseSpace()

void G4KL3DecayChannel::PhaseSpace	(	G4double	Mparent,
		const G4double *	Mdaughter,
		G4double *	Edaughter,
		G4double *	Pdaughter )

protected

Definition at line 226 of file G4KL3DecayChannel.cc.

{
  // Algorithm in this code was originally written in GDECA3 in GEANT3
 
  // sum of daughters'mass
  G4double sumofdaughtermass = 0.0;
  G4int index;
  const G4int N_DAUGHTER = 3;
 
  for (index = 0; index < N_DAUGHTER; ++index) {
    sumofdaughtermass += M[index];
  }
 
  // calculate daughter momentum. Generate two
  G4double rd1, rd2, rd;
  G4double momentummax = 0.0, momentumsum = 0.0;
  G4double energy;
  const size_t MAX_LOOP = 10000;
  for (std::size_t loop_counter = 0; loop_counter < MAX_LOOP; ++loop_counter) {
    rd1 = G4UniformRand();
    rd2 = G4UniformRand();
    if (rd2 > rd1) {
      rd = rd1;
      rd1 = rd2;
      rd2 = rd;
    }
    momentummax = 0.0;
    momentumsum = 0.0;
    // daughter 0
    energy = rd2 * (parentM - sumofdaughtermass);
    P[0] = std::sqrt(energy * energy + 2.0 * energy * M[0]);
    E[0] = energy;
    if (P[0] > momentummax) momentummax = P[0];
    momentumsum += P[0];
    // daughter 1
    energy = (1. - rd1) * (parentM - sumofdaughtermass);
    P[1] = std::sqrt(energy * energy + 2.0 * energy * M[1]);
    E[1] = energy;
    if (P[1] > momentummax) momentummax = P[1];
    momentumsum += P[1];
    // daughter 2
    energy = (rd1 - rd2) * (parentM - sumofdaughtermass);
    P[2] = std::sqrt(energy * energy + 2.0 * energy * M[2]);
    E[2] = energy;
    if (P[2] > momentummax) momentummax = P[2];
    momentumsum += P[2];
    if (momentummax <= momentumsum - momentummax) break;
  }
#ifdef G4VERBOSE
  if (GetVerboseLevel() > 2) {
    G4cout << "G4KL3DecayChannel::PhaseSpace    ";
    G4cout << "Kon mass:" << parentM / GeV << "GeV/c/c" << G4endl;
    for (index = 0; index < 3; ++index) {
      G4cout << index << " : " << M[index] / GeV << "GeV/c/c  ";
      G4cout << " : " << E[index] / GeV << "GeV  ";
      G4cout << " : " << P[index] / GeV << "GeV/c " << G4endl;
    }
  }
#endif
}

Referenced by DecayIt().

◆ SetDalitzParameter()

void G4KL3DecayChannel::SetDalitzParameter	(	G4double	aLambda,
		G4double	aXi )

inline

Definition at line 94 of file G4KL3DecayChannel.hh.

{
  pLambda = aLambda;
  pXi0 = aXi;
}

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

Public Member Functions

Protected Types

Protected Member Functions

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ anonymous enum

Constructor & Destructor Documentation

◆ G4KL3DecayChannel() [1/2]

◆ ~G4KL3DecayChannel()

◆ G4KL3DecayChannel() [2/2]

Member Function Documentation

◆ DalitzDensity()

◆ DecayIt()

◆ GetDalitzParameterLambda()

◆ GetDalitzParameterXi()

◆ operator=()

◆ PhaseSpace()

◆ SetDalitzParameter()