G4NeutronCaptureXS Class Reference

#include <G4NeutronCaptureXS.hh>

Inheritance diagram for G4NeutronCaptureXS:

Public Member Functions
	G4NeutronCaptureXS ()
	~G4NeutronCaptureXS () override=default
G4bool	IsElementApplicable (const G4DynamicParticle *, G4int Z, const G4Material *) final
G4bool	IsIsoApplicable (const G4DynamicParticle *, G4int Z, G4int A, const G4Element *, const G4Material *) final
G4double	GetElementCrossSection (const G4DynamicParticle *, G4int Z, const G4Material *) final
G4double	ComputeCrossSectionPerElement (G4double kinEnergy, G4double loge, const G4ParticleDefinition *, const G4Element *, const G4Material *) final
G4double	ComputeIsoCrossSection (G4double kinEnergy, G4double loge, const G4ParticleDefinition *, G4int Z, G4int A, const G4Isotope *iso, const G4Element *elm, const G4Material *mat) final
G4double	GetIsoCrossSection (const G4DynamicParticle *, G4int Z, G4int A, const G4Isotope *iso, const G4Element *elm, const G4Material *mat) final
const G4Isotope *	SelectIsotope (const G4Element *, G4double kinEnergy, G4double logE) final
void	BuildPhysicsTable (const G4ParticleDefinition &) final
void	CrossSectionDescription (std::ostream &) const final
G4double	ElementCrossSection (G4double kinEnergy, G4double loge, G4int Z)
G4double	IsoCrossSection (G4double ekin, G4double logekin, G4int Z, G4int A)
G4NeutronCaptureXS &	operator= (const G4NeutronCaptureXS &right)=delete
	G4NeutronCaptureXS (const G4NeutronCaptureXS &)=delete
Public Member Functions inherited from G4VCrossSectionDataSet
	G4VCrossSectionDataSet (const G4String &nam="")
virtual	~G4VCrossSectionDataSet ()
G4double	GetCrossSection (const G4DynamicParticle *, const G4Element *, const G4Material *mat=nullptr)
G4double	ComputeCrossSection (const G4DynamicParticle *, const G4Element *, const G4Material *mat=nullptr)
virtual void	DumpPhysicsTable (const G4ParticleDefinition &)
virtual void	SetVerboseLevel (G4int value)
G4double	GetMinKinEnergy () const
void	SetMinKinEnergy (G4double value)
G4double	GetMaxKinEnergy () const
void	SetMaxKinEnergy (G4double value)
bool	ForAllAtomsAndEnergies () const
void	SetForAllAtomsAndEnergies (G4bool val)
const G4String &	GetName () const
void	SetName (const G4String &nam)
G4VCrossSectionDataSet &	operator= (const G4VCrossSectionDataSet &right)=delete
	G4VCrossSectionDataSet (const G4VCrossSectionDataSet &)=delete

Static Public Member Functions
static const char *	Default_Name ()

Additional Inherited Members
Protected Attributes inherited from G4VCrossSectionDataSet
G4int	verboseLevel {0}
G4String	name

Detailed Description

Definition at line 57 of file G4NeutronCaptureXS.hh.

Constructor & Destructor Documentation

G4NeutronCaptureXS() [1/2]

G4NeutronCaptureXS::G4NeutronCaptureXS

(

)

Definition at line 67 of file G4NeutronCaptureXS.cc.

 : G4VCrossSectionDataSet(Default_Name()),
   emax(20*CLHEP::MeV), elimit(1.0e-5*CLHEP::eV)
{
  verboseLevel = 0;
  if (verboseLevel > 0) {
    G4cout  << "G4NeutronCaptureXS::G4NeutronCaptureXS: Initialise for Z < "
        << MAXZCAPTURE << G4endl;
  }
  logElimit = G4Log(elimit);
  if (nullptr == data) { 
    data = new G4ElementData(MAXZCAPTURE+1);
    data->SetName("nCapture");
    dataR = new G4ElementData(MAXZCAPTURE+1);
    dataR->SetName("nRCapture");
    FindDirectoryPath();
  }
}

Referenced by G4NeutronCaptureXS(), and operator=().

~G4NeutronCaptureXS()

G4NeutronCaptureXS::~G4NeutronCaptureXS ( )

overridedefault

G4NeutronCaptureXS() [2/2]

G4NeutronCaptureXS::G4NeutronCaptureXS ( const G4NeutronCaptureXS & )

delete

Member Function Documentation

BuildPhysicsTable()

void G4NeutronCaptureXS::BuildPhysicsTable ( const G4ParticleDefinition & p )

finalvirtual

Reimplemented from G4VCrossSectionDataSet.

Definition at line 316 of file G4NeutronCaptureXS.cc.

{
  if (verboseLevel > 0){
    G4cout << "G4NeutronCaptureXS::BuildPhysicsTable for " 
       << p.GetParticleName() << G4endl;
  }
  if (p.GetParticleName() != "neutron") { 
    G4ExceptionDescription ed;
    ed << p.GetParticleName() << " is a wrong particle type -"
       << " only neutron is allowed";
    G4Exception("G4NeutronCaptureXS::BuildPhysicsTable(..)","had012",
        FatalException, ed, "");
    return; 
  }
 
  fRfilesEnabled = G4HadronicParameters::Instance()->UseRFilesForXS();
 
  // it is possible re-initialisation for the second run
  const G4ElementTable* table = G4Element::GetElementTable();
 
  // initialise static tables only once
  std::call_once(applyOnce, [this]() { isInitializer = true; });
 
  if (isInitializer) {
    G4AutoLock l(&neutronCaptureXSMutex);
    // Access to elements
    for ( auto const & elm : *table ) {
      G4int Z = std::max( 1, std::min( elm->GetZasInt(), MAXZCAPTURE) );
      if ( nullptr == data->GetElementData(Z) ) { Initialise(Z); }
    }
    l.unlock();
  }
 
  // prepare isotope selection
  std::size_t nIso = temp.size();
  for ( auto const & elm : *table ) {
    std::size_t n = elm->GetNumberOfIsotopes();
    if (n > nIso) { nIso = n; }
  }
  temp.resize(nIso, 0.0);
}

ComputeCrossSectionPerElement()

G4double G4NeutronCaptureXS::ComputeCrossSectionPerElement ( G4double kinEnergy, G4double loge, const G4ParticleDefinition * , const G4Element * elm, const G4Material *  )

finalvirtual

Reimplemented from G4VCrossSectionDataSet.

Definition at line 124 of file G4NeutronCaptureXS.cc.

{
  G4double xs = 0.0;
  if (ekin < emax) {
    xs = ElementCrossSection(ekin, loge, elm->GetZasInt());
  }
  return xs;
}

ComputeIsoCrossSection()

G4double G4NeutronCaptureXS::ComputeIsoCrossSection ( G4double kinEnergy, G4double loge, const G4ParticleDefinition * , G4int Z, G4int A, const G4Isotope * iso, const G4Element * elm, const G4Material * mat )

finalvirtual

Reimplemented from G4VCrossSectionDataSet.

Definition at line 178 of file G4NeutronCaptureXS.cc.

{
  return IsoCrossSection(ekin, loge, Z, A); 
}

CrossSectionDescription()

void G4NeutronCaptureXS::CrossSectionDescription ( std::ostream & outFile ) const

finalvirtual

Reimplemented from G4VCrossSectionDataSet.

Definition at line 86 of file G4NeutronCaptureXS.cc.

{
  outFile << "G4NeutronCaptureXS calculates the neutron capture cross sections\n"
          << "on nuclei using data from the high precision neutron database.\n"
          << "These data are simplified and smoothed over the resonance region\n"
          << "in order to reduce CPU time. G4NeutronCaptureXS is set to zero\n"
          << "above 20 MeV for all targets. For Z > 92 the cross section of\n"
      << "Uranium is used.\n";
}

Default_Name()

const char * G4NeutronCaptureXS::Default_Name ( )

inlinestatic

Definition at line 65 of file G4NeutronCaptureXS.hh.

{return "G4NeutronCaptureXS";}

Referenced by LBE::ConstructHad(), G4NeutronCrossSectionXS::ConstructProcess(), and G4NeutronCaptureXS().

ElementCrossSection()

G4double G4NeutronCaptureXS::ElementCrossSection	(	G4double	kinEnergy,
		G4double	loge,
		G4int	Z )

Definition at line 137 of file G4NeutronCaptureXS.cc.

{
  G4int Z = std::min(ZZ, MAXZCAPTURE);
  G4double ekin = eKin;
  G4double logEkin = logE;
  if (ekin < elimit) { 
    ekin = elimit; 
    logEkin = logElimit; 
  }
 
  G4double xs;
  G4bool done{false};
  
  // data from the resonance region
  if (fRfilesEnabled) {
    auto pv = GetPhysicsVectorR(Z);
    if (nullptr != pv && ekin < cap_max_r_e[Z]) {
      const G4double e0 = pv->Energy(0);
      xs = (ekin >= e0) ? pv->LogVectorValue(ekin, logEkin) 
    : (*pv)[0]*std::sqrt(e0/ekin); 
      done = true;
    }
  }
  // data above the resonance region
  if (!done) {
    auto pv = GetPhysicsVector(Z);
    const G4double e0 = pv->Energy(0);
    xs = (ekin >= e0) ? pv->LogVectorValue(ekin, logEkin) 
      : (*pv)[0]*std::sqrt(e0/ekin);
  }
 
#ifdef G4VERBOSE
  if (verboseLevel > 1){
    G4cout << "Ekin= " << ekin/CLHEP::MeV 
           << " ElmXScap(b)= " << xs/CLHEP::barn << G4endl;
  }
#endif
  return xs;
}

Referenced by ComputeCrossSectionPerElement(), and GetElementCrossSection().

GetElementCrossSection()

G4double G4NeutronCaptureXS::GetElementCrossSection ( const G4DynamicParticle * aParticle, G4int Z, const G4Material *  )

finalvirtual

Reimplemented from G4VCrossSectionDataSet.

Definition at line 112 of file G4NeutronCaptureXS.cc.

{
  G4double xs = 0.0;
  G4double ekin = aParticle->GetKineticEnergy();
  if (ekin < emax) {
    xs = ElementCrossSection(ekin, aParticle->GetLogKineticEnergy(), Z);
  }
  return xs;
}

GetIsoCrossSection()

G4double G4NeutronCaptureXS::GetIsoCrossSection ( const G4DynamicParticle * aParticle, G4int Z, G4int A, const G4Isotope * iso, const G4Element * elm, const G4Material * mat )

finalvirtual

Reimplemented from G4VCrossSectionDataSet.

Definition at line 188 of file G4NeutronCaptureXS.cc.

{
  return IsoCrossSection(aParticle->GetKineticEnergy(), 
                         aParticle->GetLogKineticEnergy(),
                         Z, A); 
}

IsElementApplicable()

G4bool G4NeutronCaptureXS::IsElementApplicable ( const G4DynamicParticle * , G4int Z, const G4Material *  )

finalvirtual

Reimplemented from G4VCrossSectionDataSet.

Definition at line 97 of file G4NeutronCaptureXS.cc.

{
  return true;
}

IsIsoApplicable()

G4bool G4NeutronCaptureXS::IsIsoApplicable ( const G4DynamicParticle * , G4int Z, G4int A, const G4Element * , const G4Material *  )

finalvirtual

Reimplemented from G4VCrossSectionDataSet.

Definition at line 104 of file G4NeutronCaptureXS.cc.

{
  return true;
}

IsoCrossSection()

G4double G4NeutronCaptureXS::IsoCrossSection	(	G4double	ekin,
		G4double	logekin,
		G4int	Z,
		G4int	A )

Definition at line 198 of file G4NeutronCaptureXS.cc.

{
  G4double xs = 0.0;
  if (eKin > emax) { return xs; }
 
  G4int Z = std::min(ZZ, MAXZCAPTURE);
  G4double ekin = eKin;
  G4double logEkin = logE;
  if (ekin < elimit) { 
    ekin = elimit; 
    logEkin = logElimit; 
  }
 
  G4bool done{false};
 
  // data from the resonance region
  if (fRfilesEnabled) {
    auto pv = GetPhysicsVectorR(Z);
    if (nullptr != pv && ekin < cap_max_r_e[Z]) {
      // use isotope x-section if possible
      if (dataR->GetNumberOfComponents(Z) > 0) {
    auto pviso = dataR->GetComponentDataByID(Z, A);
    if (pviso != nullptr) { 
      const G4double e0 = pviso->Energy(0);
      xs = (ekin >= e0) ? pviso->LogVectorValue(ekin, logEkin)
        : (*pviso)[0]*std::sqrt(e0/ekin);
      done = true;
    }
      }
      // isotope data are not available or applicable
      if (!done) {
    const G4double e0 = pv->Energy(0);
    xs = (ekin >= e0) ? pv->LogVectorValue(ekin, logEkin)
      : (*pv)[0]*std::sqrt(e0/ekin); 
    done = true;
      }
    }
  }
  // data above the resonance region
  if (!done) { 
    auto pv = GetPhysicsVector(Z);
    // use isotope x-section if possible
    if (data->GetNumberOfComponents(Z) > 0) {
      auto pviso = data->GetComponentDataByID(Z, A);
      if (pviso != nullptr) { 
    const G4double e0 = pviso->Energy(0);
    xs = (ekin >= e0) ? pviso->LogVectorValue(ekin, logEkin)
      : (*pviso)[0]*std::sqrt(e0/ekin);
    done = true;
      }
    }
    // isotope data are not available or applicable
    if (!done) {
      const G4double e0 = pv->Energy(0);
      xs = (ekin >= e0) ? pv->LogVectorValue(ekin, logEkin)
    : (*pv)[0]*std::sqrt(e0/ekin);
    }
  }
#ifdef G4VERBOSE
  if (verboseLevel > 0) {
    G4cout << "G4NeutronCaptureXS::IsoXS: Ekin(MeV)= " << ekin/MeV 
           << "  xs(b)= " << xs/CLHEP::barn 
       << "  Z= " << Z << "  A= " << A << " no iso XS" << G4endl;
  }
#endif
  return xs;
}

Referenced by ComputeIsoCrossSection(), GetIsoCrossSection(), and SelectIsotope().

operator=()

G4NeutronCaptureXS & G4NeutronCaptureXS::operator= ( const G4NeutronCaptureXS & right )

delete

SelectIsotope()

const G4Isotope * G4NeutronCaptureXS::SelectIsotope ( const G4Element * anElement, G4double kinEnergy, G4double logE )

finalvirtual

Reimplemented from G4VCrossSectionDataSet.

Definition at line 268 of file G4NeutronCaptureXS.cc.

{
  G4int nIso = (G4int)anElement->GetNumberOfIsotopes();
  const G4Isotope* iso = anElement->GetIsotope(0);
 
  //G4cout << "SelectIsotope NIso= " << nIso << G4endl;
  if(1 == nIso) { return iso; }
 
  // more than 1 isotope
  G4int Z = anElement->GetZasInt();
  if (nullptr == data->GetElementData(Z)) { InitialiseOnFly(Z); }
 
  const G4double* abundVector = anElement->GetRelativeAbundanceVector();
  G4double q = G4UniformRand();
  G4double sum = 0.0;
 
  // is there isotope wise cross section?
  G4int j;
  if (Z > MAXZCAPTURE || 0 == data->GetNumberOfComponents(Z)) {
    for (j = 0; j<nIso; ++j) {
      sum += abundVector[j];
      if (q <= sum) {
    iso = anElement->GetIsotope(j);
    break;
      }
    }
    return iso;
  } 
  G4int nn = (G4int)temp.size();
  if (nn < nIso) { temp.resize(nIso, 0.); }
 
  for (j=0; j<nIso; ++j) {
    sum += abundVector[j]*IsoCrossSection(kinEnergy, logE, Z, 
                      anElement->GetIsotope(j)->GetN());
    temp[j] = sum;
  }
  sum *= q;
  for (j = 0; j<nIso; ++j) {
    if (temp[j] >= sum) {
      iso = anElement->GetIsotope(j);
      break;
    }
  }
  return iso;
}

---

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

• G4NeutronCaptureXS.hh
• G4NeutronCaptureXS.cc