#include <G4GammaTransition.hh>

Public Member Functions
	G4GammaTransition ()

virtual	~G4GammaTransition ()

virtual G4Fragment *	SampleTransition (G4Fragment *nucleus, G4double newExcEnergy, G4double mpRatio, G4int JP1, G4int JP2, G4int MP, G4int shell, G4bool isDiscrete, G4bool isGamma)

virtual void	SampleDirection (G4Fragment *nuc, G4double ratio, G4int twoJ1, G4int twoJ2, G4int mp)

void	SetPolarizationFlag (G4bool val)

void	SetTwoJMAX (G4int val)

void	SetVerbose (G4int val)

Protected Attributes
G4ThreeVector	fDirection

G4PolarizationTransition	fPolTrans

G4int	fTwoJMAX

G4int	fVerbose

Detailed Description

Definition at line 52 of file G4GammaTransition.hh.

Constructor & Destructor Documentation

◆ G4GammaTransition()

G4GammaTransition::G4GammaTransition ( )

explicit

Definition at line 48 of file G4GammaTransition.cc.

49 : polarFlag(false), fDirection(0.,0.,0.), fTwoJMAX(10), fVerbose(0)

50{}

G4GammaTransition::fTwoJMAX

G4int fTwoJMAX

Definition: G4GammaTransition.hh:92

G4GammaTransition::fVerbose

G4int fVerbose

Definition: G4GammaTransition.hh:93

G4GammaTransition::fDirection

G4ThreeVector fDirection

Definition: G4GammaTransition.hh:90

◆ ~G4GammaTransition()

G4GammaTransition::~G4GammaTransition ( )

virtual

Definition at line 52 of file G4GammaTransition.cc.

53{}

Member Function Documentation

◆ SampleDirection()

void G4GammaTransition::SampleDirection	(	G4Fragment *	nuc,
		G4double	ratio,
		G4int	twoJ1,
		G4int	twoJ2,
		G4int	mp
	)

virtual

Definition at line 152 of file G4GammaTransition.cc.

{
  G4double cosTheta, phi;
  G4NuclearPolarization* np = nuc->GetNuclearPolarization(); 
  if(fVerbose > 2) {
    G4cout << "G4GammaTransition::SampleDirection : 2J1= " << twoJ1 
       << " 2J2= " << twoJ2 << " ratio= " << ratio 
       << " mp= " << mp << G4endl;
    G4cout << "  Nucleus: " << *nuc << G4endl;
  }
  if(nullptr == np) {
    cosTheta = 2*G4UniformRand() - 1.0;
    phi = CLHEP::twopi*G4UniformRand();
 
  } else {
    // PhotonEvaporation dataset:
    // The multipolarity number with 1,2,3,4,5,6,7 representing E0,E1,M1,E2,M2,E3,M3
    // monopole transition and 100*Nx+Ny representing multipolarity transition with
    // Ny and Ny taking the value 1,2,3,4,5,6,7 referring to E0,E1,M1,E2,M2,E3,M3,..
    // For example a M1+E2 transition would be written 304.
    // M1 is the primary transition (L) and E2 is the secondary (L')
 
    G4double mpRatio = ratio;
 
    G4int L0 = 0, Lp = 0;
    if (mp > 99) {
      L0 = mp/200;
      Lp = (mp%100)/2;
    } else {
      L0 = mp/2;
      Lp = 0;
      mpRatio = 0.;
    } 
    fPolTrans.SampleGammaTransition(np, twoJ1, twoJ2, L0, Lp, mpRatio, cosTheta, phi);
  }
 
  G4double sinTheta = std::sqrt((1.-cosTheta)*(1.+cosTheta));
  fDirection.set(sinTheta*std::cos(phi),sinTheta*std::sin(phi),cosTheta);
  if(fVerbose > 3) {
    G4cout << "G4GammaTransition::SampleDirection done: " << fDirection << G4endl;
    if(np) { G4cout << *np << G4endl; }
  }
}

Referenced by SampleTransition().

◆ SampleTransition()

G4Fragment * G4GammaTransition::SampleTransition	(	G4Fragment *	nucleus,
		G4double	newExcEnergy,
		G4double	mpRatio,
		G4int	JP1,
		G4int	JP2,
		G4int	MP,
		G4int	shell,
		G4bool	isDiscrete,
		G4bool	isGamma
	)

virtual

Definition at line 56 of file G4GammaTransition.cc.

{
  G4Fragment* result = nullptr;
  G4double bond_energy = 0.0;
 
  if (!isGamma) { 
    if(0 <= shell) {
      G4int Z = nucleus->GetZ_asInt();
      if(Z <= 100) {
    G4int idx = (G4int)shell;
    idx = std::min(idx, G4AtomicShells::GetNumberOfShells(Z)-1);
    bond_energy = G4AtomicShells::GetBindingEnergy(Z, idx);
      }
    }
  }
  G4double etrans = nucleus->GetExcitationEnergy() - newExcEnergy 
    - bond_energy;
  if(fVerbose > 2) {
    G4cout << "G4GammaTransition::GenerateGamma - Etrans(MeV)= " 
       << etrans << "  Eexnew= " << newExcEnergy 
       << " Ebond= " << bond_energy << G4endl;
  } 
  if(etrans <= 0.0) { 
    etrans += bond_energy;
    bond_energy = 0.0;
  }
  
  // Do complete Lorentz computation 
  G4LorentzVector lv = nucleus->GetMomentum();
  G4double mass = nucleus->GetGroundStateMass() + newExcEnergy;
 
  // select secondary
  G4ParticleDefinition* part;
 
  if(isGamma) { part =  G4Gamma::Gamma(); }
  else {
    part = G4Electron::Electron();
    G4int ne = std::max(nucleus->GetNumberOfElectrons() - 1, 0);
    nucleus->SetNumberOfElectrons(ne);
  }
 
  if(polarFlag && isDiscrete && JP1 <= fTwoJMAX) {
    SampleDirection(nucleus, mpRatio, JP1, JP2, MP);
  } else {
    fDirection = G4RandomDirection();
  }
 
  G4double emass = part->GetPDGMass();
 
  // 2-body decay in rest frame
  G4double ecm       = lv.mag();
  G4ThreeVector bst  = lv.boostVector();
  if(!isGamma) { ecm += (CLHEP::electron_mass_c2 - bond_energy); }
 
  //G4cout << "Ecm= " << ecm << " mass= " << mass << " emass= " << emass << G4endl;
 
  ecm = std::max(ecm, mass + emass);
  G4double energy = 0.5*((ecm - mass)*(ecm + mass) + emass*emass)/ecm;
  G4double mom = (emass > 0.0) ? std::sqrt((energy - emass)*(energy + emass))
    : energy;
 
  // emitted gamma or e-
  G4LorentzVector res4mom(mom * fDirection.x(),
              mom * fDirection.y(),
              mom * fDirection.z(), energy);
  // residual
  energy = std::max(ecm - energy, mass);
  lv.set(-mom*fDirection.x(), -mom*fDirection.y(), -mom*fDirection.z(), energy);
 
  // Lab system transform for short lived level
  lv.boost(bst);
 
  // modified primary fragment 
  nucleus->SetExcEnergyAndMomentum(newExcEnergy, lv);
 
  // gamma or e- are produced
  res4mom.boost(bst); 
  result = new G4Fragment(res4mom, part);
 
  //G4cout << " DeltaE= " << e0 - lv.e() - res4mom.e() + emass
  //     << "   Emass= " << emass << G4endl;
  if(fVerbose > 2) {
    G4cout << "G4GammaTransition::SampleTransition : " << *result << G4endl;
    G4cout << "       Left nucleus: " << *nucleus << G4endl;
  }
  return result;
}