#include <G4WentzelVIRelXSection.hh>

Inheritance diagram for G4WentzelVIRelXSection:

Public Member Functions
G4double	ComputeElectronCrossSection (G4double CosThetaMin, G4double CosThetaMax)

G4double	ComputeNuclearCrossSection (G4double CosThetaMin, G4double CosThetaMax)

G4double	ComputeSecondTransportMoment (G4double CosThetaMax)

G4double	ComputeTransportCrossSectionPerAtom (G4double CosThetaMax)

	G4WentzelVIRelXSection ()

	G4WentzelVIRelXSection (const G4WentzelVIRelXSection &)=delete

G4double	GetCosThetaElec () const

G4double	GetCosThetaNuc () const

G4double	GetMomentumSquare () const

void	Initialise (const G4ParticleDefinition *, G4double CosThetaLim)

G4WentzelVIRelXSection &	operator= (const G4WentzelVIRelXSection &right)=delete

G4ThreeVector &	SampleSingleScattering (G4double CosThetaMin, G4double CosThetaMax, G4double elecRatio)

void	SetTargetMass (G4double value)

G4double	SetupKinematic (G4double kinEnergy, const G4Material *mat) override

void	SetupParticle (const G4ParticleDefinition *)

G4double	SetupTarget (G4int Z, G4double cut)

	~G4WentzelVIRelXSection () override

Protected Member Functions
void	ComputeMaxElectronScattering (G4double cut)

G4double	FlatFormfactor (G4double x)

void	InitialiseA ()

Protected Attributes
G4double	charge3 = 0.0

G4double	chargeSquare = 0.0

G4double	coeff

G4double	cosTetMaxElec = 1.0

G4double	cosTetMaxNuc = 1.0

G4double	cosThetaMax = -1.0

const G4Material *	currentMaterial = nullptr

G4double	ecut = DBL_MAX

G4double	etag = DBL_MAX

G4double	factB = 0.0

G4double	factD = 0.0

G4double	factorA2 = 0.0

G4Pow *	fG4pow

G4double	fMottFactor = 1.0

G4ScreeningMottCrossSection *	fMottXSection = nullptr

G4NistManager *	fNistManager

G4NuclearFormfactorType	fNucFormfactor = fExponentialNF

G4double	formfactA = 0.0

G4double	gam0pcmp = 1.0

G4double	invbeta2 = 1.0

G4bool	isCombined

G4double	kinFactor = 1.0

G4double	mass = 0.0

G4double	mom2 = 0.0

G4double	momCM2 = 0.0

G4int	nwarnings = 0

const G4ParticleDefinition *	particle = nullptr

G4double	pcmp2 = 1.0

G4double	screenZ = 0.0

G4double	spin = 0.0

G4double	targetMass

G4int	targetZ = 0

G4ThreeVector	temp

const G4ParticleDefinition *	theElectron

const G4ParticleDefinition *	thePositron

const G4ParticleDefinition *	theProton

G4double	tkin = 0.0

Static Protected Attributes
static G4double	FormFactor [100] = {0.0}

static G4double	ScreenRSquare [100] = {0.0}

static G4double	ScreenRSquareElec [100] = {0.0}

Detailed Description

Definition at line 63 of file G4WentzelVIRelXSection.hh.

Constructor & Destructor Documentation

◆ G4WentzelVIRelXSection() [1/2]

G4WentzelVIRelXSection::G4WentzelVIRelXSection ( )

explicit

Definition at line 52 of file G4WentzelVIRelXSection.cc.

53{}

◆ ~G4WentzelVIRelXSection()

G4WentzelVIRelXSection::~G4WentzelVIRelXSection ( )

override

Definition at line 57 of file G4WentzelVIRelXSection.cc.

58{}

◆ G4WentzelVIRelXSection() [2/2]

G4WentzelVIRelXSection::G4WentzelVIRelXSection ( const G4WentzelVIRelXSection & )

delete

Member Function Documentation

◆ ComputeElectronCrossSection()

G4double G4WentzelOKandVIxSection::ComputeElectronCrossSection	(	G4double	CosThetaMin,
		G4double	CosThetaMax
	)

inlineinherited

Definition at line 228 of file G4WentzelOKandVIxSection.hh.

{
  G4double cost1 = std::max(cosTMin,cosTetMaxElec);
  G4double cost2 = std::max(cosTMax,cosTetMaxElec);
  return (cost1 <= cost2) ? 0.0 : kinFactor*fMottFactor*(cost1 - cost2)/
    ((1.0 - cost1 + screenZ)*(1.0 - cost2 + screenZ));
}

References G4WentzelOKandVIxSection::cosTetMaxElec, G4WentzelOKandVIxSection::fMottFactor, G4WentzelOKandVIxSection::kinFactor, G4INCL::Math::max(), and G4WentzelOKandVIxSection::screenZ.

Referenced by G4eCoulombScatteringModel::ComputeCrossSectionPerAtom(), G4hCoulombScatteringModel::ComputeCrossSectionPerAtom(), G4WentzelVIModel::ComputeTransportXSectionPerVolume(), G4eCoulombScatteringModel::SampleSecondaries(), and G4hCoulombScatteringModel::SampleSecondaries().

◆ ComputeMaxElectronScattering()

void G4WentzelOKandVIxSection::ComputeMaxElectronScattering ( G4double cut )

protectedinherited

Definition at line 400 of file G4WentzelOKandVIxSection.cc.

{
  if(mass > MeV) {
    G4double ratio = electron_mass_c2/mass;
    G4double tau = tkin/mass;
    G4double tmax = 2.0*electron_mass_c2*tau*(tau + 2.)/
      (1.0 + 2.0*ratio*(tau + 1.0) + ratio*ratio);
    cosTetMaxElec = 1.0 - std::min(cutEnergy, tmax)*electron_mass_c2/mom2;
  } else {
 
    G4double tmax = (particle == theElectron) ? 0.5*tkin : tkin;
    G4double t = std::min(cutEnergy, tmax);
    G4double mom21 = t*(t + 2.0*electron_mass_c2);
    G4double t1 = tkin - t;
    //G4cout <<"tkin=" <<tkin<<" tmax= "<<tmax<<" t= " 
    //<<t<< " t1= "<<t1<<" cut= "<<ecut<<G4endl;
    if(t1 > 0.0) {
      G4double mom22 = t1*(t1 + 2.0*mass);
      G4double ctm = (mom2 + mom22 - mom21)*0.5/sqrt(mom2*mom22);
      if(ctm <  1.0) { cosTetMaxElec = ctm; }
      if(particle == theElectron && cosTetMaxElec < 0.0) { 
        cosTetMaxElec = 0.0; 
      }
    }
  }
}

References G4WentzelOKandVIxSection::cosTetMaxElec, source.hepunit::electron_mass_c2, G4WentzelOKandVIxSection::mass, MeV, G4INCL::Math::min(), G4WentzelOKandVIxSection::mom2, G4WentzelOKandVIxSection::particle, G4WentzelOKandVIxSection::theElectron, and G4WentzelOKandVIxSection::tkin.

Referenced by G4WentzelOKandVIxSection::SetupTarget().

◆ ComputeNuclearCrossSection()

G4double G4WentzelOKandVIxSection::ComputeNuclearCrossSection	(	G4double	CosThetaMin,
		G4double	CosThetaMax
	)

inlineinherited

Definition at line 218 of file G4WentzelOKandVIxSection.hh.

{
  return targetZ*kinFactor*fMottFactor*(cosTMin - cosTMax)/
    ((1.0 - cosTMin + screenZ)*(1.0 - cosTMax + screenZ));
}

References G4WentzelOKandVIxSection::fMottFactor, G4WentzelOKandVIxSection::kinFactor, G4WentzelOKandVIxSection::screenZ, and G4WentzelOKandVIxSection::targetZ.

Referenced by G4eCoulombScatteringModel::ComputeCrossSectionPerAtom(), G4hCoulombScatteringModel::ComputeCrossSectionPerAtom(), G4WentzelVIModel::ComputeTransportXSectionPerVolume(), G4eCoulombScatteringModel::SampleSecondaries(), and G4hCoulombScatteringModel::SampleSecondaries().

◆ ComputeSecondTransportMoment()

G4double G4WentzelOKandVIxSection::ComputeSecondTransportMoment ( G4double CosThetaMax )

inherited

Definition at line 430 of file G4WentzelOKandVIxSection.cc.

{
  return 0.0;
}

Referenced by G4WentzelVIModel::ComputeSecondMoment().

◆ ComputeTransportCrossSectionPerAtom()

G4double G4WentzelOKandVIxSection::ComputeTransportCrossSectionPerAtom ( G4double CosThetaMax )

inherited

Definition at line 248 of file G4WentzelOKandVIxSection.cc.

{
  G4double xSection = 0.0;
  if(cosTMax >= 1.0) { return xSection; }
 
  G4double costm = std::max(cosTMax,cosTetMaxElec); 
  G4double fb = screenZ*factB;
 
  // scattering off electrons
  if(costm < 1.0) {
    G4double x = (1.0 - costm)/screenZ;
    if(x < numlimit) { 
      G4double x2 = 0.5*x*x;
      xSection = x2*((1.0 - 1.3333333*x + 3*x2) - fb*x*(0.6666667 - x)); 
    } else { 
      G4double x1= x/(1 + x);
      G4double xlog = G4Log(1.0 + x);  
      xSection = xlog - x1 - fb*(x + x1 - 2*xlog);
    }
 
    if(xSection < 0.0) {
      ++nwarnings;
      if(nwarnings < nwarnlimit) {
        G4cout << "G4WentzelOKandVIxSection::ComputeTransportCrossSectionPerAtom"
               << " scattering on e- <0"
               << G4endl;
        G4cout << "cross= " << xSection
               << " e(MeV)= " << tkin << " p(MeV/c)= " << sqrt(mom2) 
               << " Z= " << targetZ << "  " 
               << particle->GetParticleName() << G4endl;
        G4cout << " 1-costm= " << 1.0-costm << " screenZ= " << screenZ 
               << " x= " << x << G4endl;
      }
      xSection = 0.0;
    }
  }
  /*  
      G4cout << "G4WentzelOKandVIxSection::ComputeTransportCrossSectionPerAtom: \n"
      << " Z= " << targetZ 
      << " e(MeV)= " << tkin/MeV << " XSel= " << xSection  
      << " zmaxE= " << (1.0 - cosTetMaxElec)/screenZ 
      << " zmaxN= " << (1.0 - cosThetaMax)/screenZ 
      << " 1-costm= " << 1.0 - cosThetaMax << G4endl;
  */
  // scattering off nucleus
  if(cosTMax < 1.0) {
    G4double x = (1.0 - cosTMax)/screenZ;
    G4double y;
    if(x < numlimit) { 
      G4double x2 = 0.5*x*x;
      y = x2*((1.0 - 1.3333333*x + 3*x2) - fb*x*(0.6666667 - x)); 
    } else { 
      G4double x1= x/(1 + x);
      G4double xlog = G4Log(1.0 + x);  
      y = xlog - x1 - fb*(x + x1 - 2*xlog); 
    }
 
    if(y < 0.0) {
      ++nwarnings;
      if(nwarnings < nwarnlimit) {
        G4cout << "G4WentzelOKandVIxSection::ComputeTransportCrossSectionPerAtom"
               << " scattering on nucleus <0"
               << G4endl;
        G4cout << "y= " << y 
               << " e(MeV)= " << tkin << " Z= " << targetZ << "  " 
               << particle->GetParticleName() << G4endl;
        G4cout << " formfactA= " << formfactA << " screenZ= " << screenZ 
               << " x= " << x <<G4endl;
      }
      y = 0.0;
    }
    xSection += y*targetZ; 
  }
  xSection *= kinFactor;
 
  /* 
  G4cout << "Z= " << targetZ << " XStot= " << xSection/barn 
         << " screenZ= " << screenZ << " formF= " << formfactA 
         << " for " << particle->GetParticleName() 
     << " m= " << mass << " 1/v= " << sqrt(invbeta2) 
     << " p= " << sqrt(mom2)
         << " x= " << x << G4endl;
  */
  return xSection; 
}

References G4WentzelOKandVIxSection::cosTetMaxElec, G4WentzelOKandVIxSection::factB, G4WentzelOKandVIxSection::formfactA, G4cout, G4endl, G4Log(), G4ParticleDefinition::GetParticleName(), G4WentzelOKandVIxSection::kinFactor, G4INCL::Math::max(), G4WentzelOKandVIxSection::mom2, numlimit, G4WentzelOKandVIxSection::nwarnings, nwarnlimit, G4WentzelOKandVIxSection::particle, G4WentzelOKandVIxSection::screenZ, G4WentzelOKandVIxSection::targetZ, and G4WentzelOKandVIxSection::tkin.

Referenced by G4WentzelVIModel::ComputeCrossSectionPerAtom(), G4WentzelVIRelModel::ComputeCrossSectionPerAtom(), and G4WentzelVIModel::ComputeTransportXSectionPerVolume().

◆ FlatFormfactor()

G4double G4WentzelOKandVIxSection::FlatFormfactor ( G4double x )

inlineprotectedinherited

Definition at line 237 of file G4WentzelOKandVIxSection.hh.

{
  return 3.0*(std::sin(x) - x*std::cos(x))/(x*x*x);
}

Referenced by G4WentzelOKandVIxSection::SampleSingleScattering().

◆ GetCosThetaElec()

G4double G4WentzelOKandVIxSection::GetCosThetaElec ( ) const

inlineinherited

Definition at line 210 of file G4WentzelOKandVIxSection.hh.

{
  return cosTetMaxElec;
}

References G4WentzelOKandVIxSection::cosTetMaxElec.

◆ GetCosThetaNuc()

G4double G4WentzelOKandVIxSection::GetCosThetaNuc ( ) const

inlineinherited

Definition at line 203 of file G4WentzelOKandVIxSection.hh.

{
  return cosTetMaxNuc;
}

References G4WentzelOKandVIxSection::cosTetMaxNuc.

◆ GetMomentumSquare()

G4double G4WentzelOKandVIxSection::GetMomentumSquare ( ) const

inlineinherited

Definition at line 196 of file G4WentzelOKandVIxSection.hh.

{
  return mom2;
}

References G4WentzelOKandVIxSection::mom2.

Referenced by G4eCoulombScatteringModel::SampleSecondaries().

◆ Initialise()

void G4WentzelOKandVIxSection::Initialise	(	const G4ParticleDefinition *	p,
		G4double	CosThetaLim
	)

inherited

Definition at line 100 of file G4WentzelOKandVIxSection.cc.

{
  SetupParticle(p);
  tkin = mom2 = momCM2 = 0.0;
  ecut = etag = DBL_MAX;
  targetZ = 0;
 
  // cosThetaMax is below 1.0 only when MSC is combined with SS
  if(isCombined) { cosThetaMax = cosThetaLim; } 
  G4EmParameters* param = G4EmParameters::Instance();
  G4double a = param->FactorForAngleLimit()*CLHEP::hbarc/CLHEP::fermi;
  factorA2 = 0.5*a*a;
  currentMaterial = nullptr;
 
  fNucFormfactor = param->NuclearFormfactorType();
  if(0.0 == ScreenRSquare[0]) { InitialiseA(); }
 
  // Mott corrections always added
  if((p == theElectron || p == thePositron) && !fMottXSection) {
    fMottXSection = new G4ScreeningMottCrossSection();
    fMottXSection->Initialise(p, 1.0);
  }
  /*
  G4cout << "G4WentzelOKandVIxSection::Initialise for " 
     << p->GetParticleName() << " cosThetaMax= " << cosThetaMax 
     << "  " << ScreenRSquare[0] << " coeff= " << coeff << G4endl;
  */
}

Referenced by G4eCoulombScatteringModel::Initialise(), G4hCoulombScatteringModel::Initialise(), and G4WentzelVIModel::Initialise().

◆ InitialiseA()

void G4WentzelOKandVIxSection::InitialiseA ( )

protectedinherited

Definition at line 132 of file G4WentzelOKandVIxSection.cc.

{
  // Thomas-Fermi screening radii
  // Formfactors from A.V. Butkevich et al., NIM A 488 (2002) 282
#ifdef G4MULTITHREADED
  G4MUTEXLOCK(&G4WentzelOKandVIxSection::WentzelOKandVIxSectionMutex);
  if(0.0 == ScreenRSquare[0]) {
#endif
    const G4double invmev2 = 1./(CLHEP::MeV*CLHEP::MeV);
    G4double a0 = CLHEP::electron_mass_c2/0.88534; 
    G4double constn = 6.937e-6*invmev2;
    G4double fct = G4EmParameters::Instance()->ScreeningFactor();
 
    G4double afact = 0.5*fct*alpha2*a0*a0;
    ScreenRSquare[0] = afact;
    ScreenRSquare[1] = afact;
    ScreenRSquareElec[1] = afact; 
    FormFactor[1] = 3.097e-6*invmev2;
 
    for(G4int j=2; j<100; ++j) {
      G4double x = fG4pow->Z13(j);
      ScreenRSquare[j] = afact*(1 + G4Exp(-j*j*0.001))*x*x;
      ScreenRSquareElec[j] = afact*x*x;
      x = fNistManager->GetA27(j);
      FormFactor[j] = constn*x*x;
    } 
#ifdef G4MULTITHREADED
  }
  G4MUTEXUNLOCK(&G4WentzelOKandVIxSection::WentzelOKandVIxSectionMutex);
#endif
  
  //G4cout << "G4WentzelOKandVIxSection::Initialise  mass= " << mass
  //         << "  " << p->GetParticleName() 
  //     << "  cosThetaMax= " << cosThetaMax << G4endl; 
  
}

References a0, alpha2, CLHEP::electron_mass_c2, G4WentzelOKandVIxSection::fG4pow, G4WentzelOKandVIxSection::fNistManager, G4WentzelOKandVIxSection::FormFactor, G4Exp(), G4MUTEXLOCK, G4MUTEXUNLOCK, G4NistManager::GetA27(), G4EmParameters::Instance(), CLHEP::MeV, G4EmParameters::ScreeningFactor(), G4WentzelOKandVIxSection::ScreenRSquare, G4WentzelOKandVIxSection::ScreenRSquareElec, and G4Pow::Z13().

Referenced by G4WentzelOKandVIxSection::Initialise().

◆ operator=()

G4WentzelVIRelXSection & G4WentzelVIRelXSection::operator= ( const G4WentzelVIRelXSection & right )

delete

◆ SampleSingleScattering()

G4ThreeVector & G4WentzelOKandVIxSection::SampleSingleScattering	(	G4double	CosThetaMin,
		G4double	CosThetaMax,
		G4double	elecRatio
	)

inherited

Definition at line 337 of file G4WentzelOKandVIxSection.cc.

{
  temp.set(0.0,0.0,1.0);
  CLHEP::HepRandomEngine* rndmEngineMod = G4Random::getTheEngine();
 
  G4double formf = formfactA;
  G4double cost1 = cosTMin;
  G4double cost2 = cosTMax;
  if(elecRatio > 0.0) {
    if(rndmEngineMod->flat() <= elecRatio) {
      formf = 0.0;
      cost1 = std::max(cost1,cosTetMaxElec);
      cost2 = std::max(cost2,cosTetMaxElec);
    }
  }
  if(cost1 > cost2) {
 
    G4double w1 = 1. - cost1 + screenZ;
    G4double w2 = 1. - cost2 + screenZ;
    G4double z1 = w1*w2/(w1 + rndmEngineMod->flat()*(w2 - w1)) - screenZ;
 
    G4double fm = 1.0;
    if(fNucFormfactor == fExponentialNF) {
      fm += formf*z1;
      fm = 1.0/(fm*fm);
    } else if(fNucFormfactor == fGaussianNF) {
      fm = G4Exp(-2*formf*z1);
    } else if(fNucFormfactor == fFlatNF) {
      static const G4double ccoef = 0.00508/MeV;
      G4double x = std::sqrt(2.*mom2*z1)*ccoef*2.;
      fm = FlatFormfactor(x);
      fm *= FlatFormfactor(x*0.6
        *fG4pow->A13(fNistManager->GetAtomicMassAmu(targetZ)));
    }
    G4double grej;
    if(fMottXSection) {
      fMottXSection->SetupKinematic(tkin, targetZ);
      grej = fMottXSection->RatioMottRutherfordCosT(std::sqrt(z1))*fm*fm;
    } else {
      grej = (1. - z1*factB + factB1*targetZ*sqrt(z1*factB)*(2. - z1))
      *fm*fm/(1.0 + z1*factD);
    }
    // G4cout << "SampleSingleScattering: E= " << tkin << " z1= " 
    //     << z1 << " grej= "<< grej << " mottFact= "<< fMottFactor<< G4endl;
    if(fMottFactor*rndmEngineMod->flat() <= grej ) {
      // exclude "false" scattering due to formfactor and spin effect
      G4double cost = 1.0 - z1;
      if(cost > 1.0)       { cost = 1.0; }
      else if(cost < -1.0) { cost =-1.0; }
      G4double sint = sqrt((1.0 - cost)*(1.0 + cost));
      //G4cout << "sint= " << sint << G4endl;
      G4double phi  = twopi*rndmEngineMod->flat();
      temp.set(sint*cos(phi),sint*sin(phi),cost);
    }
  }
  return temp;
}

Referenced by G4WentzelVIModel::SampleScattering(), G4eCoulombScatteringModel::SampleSecondaries(), and G4hCoulombScatteringModel::SampleSecondaries().

◆ SetTargetMass()

void G4WentzelOKandVIxSection::SetTargetMass ( G4double value )

inlineinherited

Definition at line 188 of file G4WentzelOKandVIxSection.hh.

{
  targetMass = value;
  factD = std::sqrt(mom2)/value;
}

References G4WentzelOKandVIxSection::factD, G4WentzelOKandVIxSection::mom2, and G4WentzelOKandVIxSection::targetMass.

Referenced by G4hCoulombScatteringModel::ComputeCrossSectionPerAtom(), G4WentzelVIRelModel::ComputeCrossSectionPerAtom(), G4WentzelVIRelModel::DefineMaterial(), G4eCoulombScatteringModel::SampleSecondaries(), G4hCoulombScatteringModel::SampleSecondaries(), and G4WentzelOKandVIxSection::SetupTarget().

◆ SetupKinematic()

G4double G4WentzelVIRelXSection::SetupKinematic	(	G4double	kinEnergy,
		const G4Material *	mat
	)

overridevirtual

Reimplemented from G4WentzelOKandVIxSection.

Definition at line 62 of file G4WentzelVIRelXSection.cc.

{
  if(kinEnergy != tkin || mat != currentMaterial) { 
 
    currentMaterial = mat;
    tkin  = kinEnergy;
    G4double momLab2  = tkin*(tkin + 2.0*mass);
    
    G4double etot = tkin + mass;
    G4double ptot = std::sqrt(momLab2);
    G4double m12  = mass*mass;
 
    // relativistic reduced mass from publucation
    // A.P. Martynenko, R.N. Faustov, Teoret. mat. Fiz. 64 (1985) 179
        
    //incident particle & target nucleus
    G4double Ecm = std::sqrt(m12 + targetMass*targetMass + 2.0*etot*targetMass);
    G4double mu_rel = mass*targetMass/Ecm;
    G4double momCM  = ptot*targetMass/Ecm;
    // relative system
    mom2 = momCM*momCM;
    invbeta2 = 1.0 +  mu_rel*mu_rel/mom2;
 
    factB = spin/invbeta2;
    factD = std::sqrt(mom2)/targetMass;
    cosTetMaxNuc = isCombined ? 
      std::max(cosThetaMax, 1.-factorA2*mat->GetIonisation()->GetInvA23()/mom2)
      : cosThetaMax;
  } 
  return cosTetMaxNuc;
}

Referenced by G4hCoulombScatteringModel::ComputeCrossSectionPerAtom(), and G4hCoulombScatteringModel::SampleSecondaries().

◆ SetupParticle()

void G4WentzelOKandVIxSection::SetupParticle ( const G4ParticleDefinition * p )

inherited

Definition at line 171 of file G4WentzelOKandVIxSection.cc.

{
  particle = p;
  mass = particle->GetPDGMass();
  spin = particle->GetPDGSpin();
  if(0.0 != spin) { spin = 0.5; }
  G4double q = std::abs(particle->GetPDGCharge()/eplus);
  chargeSquare = q*q;
  charge3 = chargeSquare*q;
  tkin = 0.0;
  currentMaterial = nullptr;
  targetZ = 0;
}

References G4WentzelOKandVIxSection::charge3, G4WentzelOKandVIxSection::chargeSquare, G4WentzelOKandVIxSection::currentMaterial, eplus, G4ParticleDefinition::GetPDGCharge(), G4ParticleDefinition::GetPDGMass(), G4ParticleDefinition::GetPDGSpin(), G4WentzelOKandVIxSection::mass, G4WentzelOKandVIxSection::particle, G4WentzelOKandVIxSection::spin, G4WentzelOKandVIxSection::targetZ, and G4WentzelOKandVIxSection::tkin.

Referenced by G4WentzelOKandVIxSection::Initialise(), G4eCoulombScatteringModel::SetupParticle(), G4hCoulombScatteringModel::SetupParticle(), and G4WentzelVIModel::SetupParticle().

◆ SetupTarget()

G4double G4WentzelOKandVIxSection::SetupTarget	(	G4int	Z,
		G4double	cut
	)

inherited

Definition at line 206 of file G4WentzelOKandVIxSection.cc.

{
  G4double cosTetMaxNuc2 = cosTetMaxNuc;
  if(Z != targetZ || tkin != etag) {
    etag    = tkin; 
    targetZ = std::min(Z, 99);
    G4double massT = (1 == Z) ? CLHEP::proton_mass_c2 :
      fNistManager->GetAtomicMassAmu(Z)*CLHEP::amu_c2;
    SetTargetMass(massT);
 
    kinFactor = coeff*Z*chargeSquare*invbeta2/mom2;
    if(particle == theElectron && fMottXSection) {
      fMottFactor = (1.0 + 2.0e-4*Z*Z);
    }
 
    if(1 == Z) {
      screenZ = ScreenRSquare[targetZ]/mom2;
    } else if(mass > MeV) {
      screenZ = std::min(Z*1.13,1.13 +3.76*Z*Z*invbeta2*alpha2*chargeSquare)*
        ScreenRSquare[targetZ]/mom2;
    } else {
      G4double tau = tkin/mass;
      screenZ = std::min(Z*1.13,(1.13 +3.76*Z*Z
          *invbeta2*alpha2*std::sqrt(tau/(tau + fG4pow->Z23(targetZ)))))*
        ScreenRSquareElec[targetZ]/mom2;
    }
    if(targetZ == 1 && particle == theProton && cosTetMaxNuc2 < 0.0) {
      cosTetMaxNuc2 = 0.0;
    }
    formfactA = FormFactor[targetZ]*mom2;
 
    cosTetMaxElec = 1.0;
    ComputeMaxElectronScattering(cut); 
  }
  //G4cout << "SetupTarget:  Z= " << targetZ << " kinFactor= " << kinFactor
  //     << " fMottFactor= " << fMottFactor << " screenZ= " << screenZ <<G4endl;
  return cosTetMaxNuc2;
} 