G4NeutronBetaDecayChannel Class Reference

#include <G4NeutronBetaDecayChannel.hh>

Inheritance diagram for G4NeutronBetaDecayChannel:

Public Member Functions
	G4NeutronBetaDecayChannel (const G4String &theParentName, G4double theBR)
virtual	~G4NeutronBetaDecayChannel ()
virtual G4DecayProducts *	DecayIt (G4double)
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="")
virtual	~G4VDecayChannel ()
G4int	operator== (const G4VDecayChannel &right) const
G4int	operator!= (const G4VDecayChannel &right) const
G4int	operator< (const G4VDecayChannel &right) const
virtual G4DecayProducts *	DecayIt (G4double parentMass=-1.0)=0
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 ()

Protected Member Functions
	G4NeutronBetaDecayChannel (const G4NeutronBetaDecayChannel &)
G4NeutronBetaDecayChannel &	operator= (const G4NeutronBetaDecayChannel &)
	G4NeutronBetaDecayChannel ()
Protected Member Functions inherited from G4VDecayChannel
	G4VDecayChannel ()
	G4VDecayChannel (const G4VDecayChannel &)
G4VDecayChannel &	operator= (const G4VDecayChannel &)
void	ClearDaughtersName ()
void	FillDaughters ()
void	FillParent ()

Protected Attributes
const G4double	aENuCorr
Protected Attributes inherited from G4VDecayChannel
G4String	kinematics_name
G4double	rbranch
G4int	numberOfDaughters
G4String *	parent_name
G4String **	daughters_name
G4ParticleTable *	particletable
G4ParticleDefinition *	parent
G4ParticleDefinition **	daughters
G4double	parent_mass
G4double *	daughters_mass
G4int	verboseLevel

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

Detailed Description

Definition at line 43 of file G4NeutronBetaDecayChannel.hh.

Constructor & Destructor Documentation

G4NeutronBetaDecayChannel() [1/3]

G4NeutronBetaDecayChannel::G4NeutronBetaDecayChannel	(	const G4String &	theParentName,
		G4double	theBR
	)

Definition at line 57 of file G4NeutronBetaDecayChannel.cc.

                   :G4VDecayChannel("Neutron Decay"),
            aENuCorr(-0.102)
{
  // set names for daughter particles
  if (theParentName == "neutron") {
    SetBR(theBR);
    SetParent("neutron");
    SetNumberOfDaughters(3);
    SetDaughter(0, "e-");
    SetDaughter(1, "anti_nu_e");
    SetDaughter(2, "proton");
  } else if (theParentName == "anti_neutron") {
    SetBR(theBR);
    SetParent("anti_neutron");
    SetNumberOfDaughters(3);
    SetDaughter(0, "e+");
    SetDaughter(1, "nu_e");
    SetDaughter(2, "anti_proton");
  } else {
#ifdef G4VERBOSE
    if (GetVerboseLevel()>0) {
      G4cout << "G4NeutronBetaDecayChannel:: constructor :";
      G4cout << " parent particle is not neutron but ";
      G4cout << theParentName << G4endl;
    }
#endif
  }
}

~G4NeutronBetaDecayChannel()

G4NeutronBetaDecayChannel::~G4NeutronBetaDecayChannel ( )

virtual

Definition at line 89 of file G4NeutronBetaDecayChannel.cc.

{
}

G4NeutronBetaDecayChannel() [2/3]

G4NeutronBetaDecayChannel::G4NeutronBetaDecayChannel ( const G4NeutronBetaDecayChannel &  right )

protected

Definition at line 93 of file G4NeutronBetaDecayChannel.cc.

    : G4VDecayChannel(right),
      aENuCorr(-0.102)
{
}

G4NeutronBetaDecayChannel() [3/3]

G4NeutronBetaDecayChannel::G4NeutronBetaDecayChannel ( )

protected

Definition at line 51 of file G4NeutronBetaDecayChannel.cc.

                   :G4VDecayChannel(),
            aENuCorr(-0.102)
{
}

Member Function Documentation

DecayIt()

G4DecayProducts * G4NeutronBetaDecayChannel::DecayIt ( G4double  )

virtual

Implements G4VDecayChannel.

Definition at line 127 of file G4NeutronBetaDecayChannel.cc.

{
  //  This class describes free neutron beta decay  kinemtics.
  //  This version neglects neutron/electron polarization  
  //  without Coulomb effect
 
#ifdef G4VERBOSE
  if (GetVerboseLevel()>1) G4cout << "G4NeutronBetaDecayChannel::DecayIt ";
#endif
 
  if (parent == 0) FillParent();  
  if (daughters == 0) FillDaughters();
 
  // parent mass
  G4double parentmass = parent->GetPDGMass();
 
  //daughters'mass
  G4double daughtermass[3]; 
  G4double sumofdaughtermass = 0.0;
  for (G4int index=0; index<3; index++){
    daughtermass[index] = daughters[index]->GetPDGMass();
    sumofdaughtermass += daughtermass[index];
  }
  G4double xmax = parentmass-sumofdaughtermass;  
 
   //create parent G4DynamicParticle at rest
  G4ThreeVector dummy;
  G4DynamicParticle * parentparticle = new G4DynamicParticle( parent, dummy, 0.0);
 
  //create G4Decayproducts
  G4DecayProducts *products = new G4DecayProducts(*parentparticle);
  delete parentparticle;
 
  // calculate daughter momentum
  G4double daughtermomentum[3];
 
  // calcurate electron energy
  G4double x;                    // Ee
  G4double p;                    // Pe
  G4double dm = daughtermass[0]; //Me
  G4double w;                    // cosine of e-nu angle
  G4double r;  
  G4double r0;
  do {
      x = xmax*G4UniformRand();
      p = std::sqrt(x*(x+2.0*dm));
      w = 1.0-2.0*G4UniformRand();
      r = p*(x+dm)*(xmax-x)*(xmax-x)*(1.0+aENuCorr*p/(x+dm)*w);
      r0 = G4UniformRand()*(xmax+dm)*(xmax+dm)*xmax*xmax*(1.0+aENuCorr);
  } while (r < r0);    
 
 
  //create daughter G4DynamicParticle 
  // rotation materix to lab frame
  G4double costheta = 2.*G4UniformRand()-1.0;
  G4double theta = std::acos(costheta)*rad;
  G4double phi  = twopi*G4UniformRand()*rad;
  G4RotationMatrix rm;
  rm.rotateY(theta);
  rm.rotateZ(phi);
 
  // daughter 0 (electron) in Z direction
  daughtermomentum[0] = p;
  G4ThreeVector direction0(0.0, 0.0, 1.0);
  direction0 = rm * direction0;
  G4DynamicParticle * daughterparticle0 
         = new G4DynamicParticle( daughters[0], direction0*daughtermomentum[0]);
  products->PushProducts(daughterparticle0);
 
  // daughter 1 (nutrino) in XZ plane
  G4double eNu;    // Enu
  eNu = (parentmass-daughtermass[2])*(parentmass+daughtermass[2])+(dm*dm)-2.*parentmass*(x+dm);
  eNu /= 2.*(parentmass+p*w-(x+dm));
  G4double cosn = w;
  G4double sinn = std::sqrt((1.0-cosn)*(1.0+cosn));
 
  G4ThreeVector direction1(sinn, 0.0, cosn);
  direction1 = rm * direction1;
  G4DynamicParticle * daughterparticle1 
         = new G4DynamicParticle( daughters[1], direction1*eNu);
  products->PushProducts(daughterparticle1);
 
  // daughter 2 (proton) at REST
  G4double eP;     // Eproton
  eP = parentmass-eNu-(x+dm)-daughtermass[2];
  G4double pPx = -eNu*sinn;
  G4double pPz = -p-eNu*cosn;
  G4double pP  = std::sqrt(eP*(eP+2.*daughtermass[2]));
  G4ThreeVector direction2(pPx/pP, 0.0, pPz/pP);
    G4DynamicParticle * daughterparticle2 
         = new G4DynamicParticle( daughters[2], direction2);
  products->PushProducts(daughterparticle2);
 
 
 // output message
#ifdef G4VERBOSE
  if (GetVerboseLevel()>1) {
    G4cout << "G4NeutronBetaDecayChannel::DecayIt ";
    G4cout << "  create decay products in rest frame " <<G4endl;
    products->DumpInfo();
  }
#endif
  return products;
}

operator=()

G4NeutronBetaDecayChannel & G4NeutronBetaDecayChannel::operator= ( const G4NeutronBetaDecayChannel &  right )

protected

Definition at line 100 of file G4NeutronBetaDecayChannel.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 !=0) 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]);
      }
    }
  }
  return *this;
}

Member Data Documentation

aENuCorr

const G4double G4NeutronBetaDecayChannel::aENuCorr

protected

Definition at line 70 of file G4NeutronBetaDecayChannel.hh.

Referenced by DecayIt().

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

• G4NeutronBetaDecayChannel.hh
• G4NeutronBetaDecayChannel.cc