#include <G4IonCoulombCrossSection.hh>

Public Member Functions
	G4IonCoulombCrossSection ()

	G4IonCoulombCrossSection (const G4IonCoulombCrossSection &)=delete

G4double	GetMomentum2 ()

void	Initialise (const G4ParticleDefinition *, G4double cosThetaLim)

G4double	NuclearCrossSection ()

G4IonCoulombCrossSection &	operator= (const G4IonCoulombCrossSection &right)=delete

G4double	SampleCosineTheta ()

void	SetupKinematic (G4double kinEnergy, G4double tmass)

void	SetupParticle (const G4ParticleDefinition *)

void	SetupTarget (G4double Z, G4double kinEnergy, G4int heavycorr)

	~G4IonCoulombCrossSection ()

Private Member Functions
void	SetScreenRSquare (G4int iz)

Private Attributes
G4double	alpha2

G4double	chargeSquare

G4double	coeff

G4double	cosTetMaxNuc

G4double	cosTetMinNuc

G4double	cosThetaMax

G4double	cosThetaMin

G4double	etag

G4Pow *	fG4pow

G4NistManager *	fNistManager

G4double	invbeta2

G4double	invbetaLab2

G4double	mass

G4double	mom2

G4double	momLab2

G4double	nucXSection

const G4ParticleDefinition *	particle

G4double	ScreenRSquare

G4double	screenZ

G4double	spin

G4double	targetMass

G4double	targetZ

const G4ParticleDefinition *	theProton

G4double	tkin

G4double	tkinLab

Detailed Description

Definition at line 69 of file G4IonCoulombCrossSection.hh.

Constructor & Destructor Documentation

◆ G4IonCoulombCrossSection() [1/2]

G4IonCoulombCrossSection::G4IonCoulombCrossSection ( )

explicit

Definition at line 70 of file G4IonCoulombCrossSection.cc.

                                                  :
   cosThetaMin(1.0),
   cosThetaMax(-1.0),
   alpha2(fine_structure_const*fine_structure_const)
{
  fNistManager = G4NistManager::Instance();
  fG4pow = G4Pow::GetInstance();
  theProton   = G4Proton::Proton();
  particle=0;
 
  G4double p0 = electron_mass_c2*classic_electr_radius;
  coeff  = twopi*p0*p0;
 
  cosTetMinNuc=0;
  cosTetMaxNuc=0;
  nucXSection =0;
 
  chargeSquare = spin = mass = 0.0;
  tkinLab = momLab2 = invbetaLab2 = tkin = mom2 = invbeta2 = 0.0;
 
  targetZ = targetMass = screenZ = ScreenRSquare = etag = 0.0;
}

References chargeSquare, source.hepunit::classic_electr_radius, coeff, cosTetMaxNuc, cosTetMinNuc, source.hepunit::electron_mass_c2, etag, fG4pow, fNistManager, G4Pow::GetInstance(), G4NistManager::Instance(), invbeta2, invbetaLab2, mass, mom2, momLab2, nucXSection, particle, G4Proton::Proton(), ScreenRSquare, screenZ, spin, targetMass, targetZ, theProton, tkin, tkinLab, and twopi.

◆ ~G4IonCoulombCrossSection()

G4IonCoulombCrossSection::~G4IonCoulombCrossSection ( )

Definition at line 94 of file G4IonCoulombCrossSection.cc.

95{}

◆ G4IonCoulombCrossSection() [2/2]

G4IonCoulombCrossSection::G4IonCoulombCrossSection ( const G4IonCoulombCrossSection & )

delete

Member Function Documentation

◆ GetMomentum2()

G4double G4IonCoulombCrossSection::GetMomentum2 ( )

inline

Definition at line 159 of file G4IonCoulombCrossSection.hh.

{
  return mom2;
}

References mom2.

◆ Initialise()

void G4IonCoulombCrossSection::Initialise	(	const G4ParticleDefinition *	p,
		G4double	cosThetaLim
	)

Definition at line 99 of file G4IonCoulombCrossSection.cc.

{
  SetupParticle(p);
  nucXSection = tkin = targetZ = mom2 = 0.0;
  etag = DBL_MAX;
  particle = p;     
  cosThetaMin = CosThetaLim; 
}

References cosThetaMin, DBL_MAX, etag, mom2, nucXSection, particle, SetupParticle(), targetZ, and tkin.

Referenced by G4IonCoulombScatteringModel::Initialise().

◆ NuclearCrossSection()

G4double G4IonCoulombCrossSection::NuclearCrossSection ( )

Definition at line 190 of file G4IonCoulombCrossSection.cc.

{
  // This method needs initialisation before be called
  // scattering with target nucleus
  G4double fac = coeff*targetZ*(targetZ)*chargeSquare*invbeta2/mom2;
 
  nucXSection  = 0.0;
 
  G4double x  = 1.0 - cosTetMinNuc;
  G4double x1 = x + screenZ;
 
  // scattering with nucleus
  if(cosTetMaxNuc < cosTetMinNuc) {
    nucXSection = fac*(cosTetMinNuc - cosTetMaxNuc)/
      (x1*(1.0 - cosTetMaxNuc + screenZ));
  }
 
  return nucXSection;
}

References chargeSquare, coeff, cosTetMaxNuc, cosTetMinNuc, fac, invbeta2, mom2, nucXSection, screenZ, and targetZ.

Referenced by G4IonCoulombScatteringModel::ComputeCrossSectionPerAtom().

◆ operator=()

G4IonCoulombCrossSection & G4IonCoulombCrossSection::operator= ( const G4IonCoulombCrossSection & right )

delete

◆ SampleCosineTheta()

G4double G4IonCoulombCrossSection::SampleCosineTheta ( )

Definition at line 212 of file G4IonCoulombCrossSection.cc.

{   
  G4double z1 = 0.0;
  if(cosTetMaxNuc < cosTetMinNuc) {
 
    G4double x1 = 1. - cosTetMinNuc + screenZ;
    G4double x2 = 1. - cosTetMaxNuc + screenZ;
    G4double dx = cosTetMinNuc - cosTetMaxNuc;
    z1 = x1*x2/(x1 + G4UniformRand()*dx) - screenZ;
  }
  return z1;
}

References cosTetMaxNuc, cosTetMinNuc, G4UniformRand, and screenZ.

Referenced by G4IonCoulombScatteringModel::SampleSecondaries().

◆ SetScreenRSquare()

void G4IonCoulombCrossSection::SetScreenRSquare ( G4int iz )

private

Definition at line 171 of file G4IonCoulombCrossSection.cc.

{
  //for proton Thomas-Fermi screening length    
  G4int Z1 = G4lrint(std::sqrt(chargeSquare));
  G4double Z113  = fG4pow->Z13(iz);
  G4double Z1023 = fG4pow->powZ(Z1,0.23);
  G4double Z2023 = fG4pow->powZ(iz,0.23);
  G4double x=a0*(Z1023+Z2023);  
              
  // Universal screening length
  if(particle == theProton){
     x = a0*Z113;
  } 
 
  ScreenRSquare = alpha2*x*x;
}

References a0, alpha2, chargeSquare, fG4pow, G4lrint(), particle, G4Pow::powZ(), ScreenRSquare, theProton, anonymous_namespace{paraMaker.cc}::Z1, and G4Pow::Z13().

Referenced by SetupTarget().

◆ SetupKinematic()

void G4IonCoulombCrossSection::SetupKinematic	(	G4double	kinEnergy,
		G4double	tmass
	)

Definition at line 111 of file G4IonCoulombCrossSection.cc.

{
  if(ekin != tkinLab || tmass != targetMass) {
 
    // lab
    tkinLab = ekin;
    momLab2 = tkinLab*(tkinLab + 2.0*mass);
    invbetaLab2 = 1.0 +  mass*mass/momLab2;
 
    G4double etot = tkinLab + mass;
    G4double ptot = 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
    targetMass = tmass;
    G4double Ecm=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;
    tkin = momCM*sqrt(invbeta2) - mu_rel;//Ekin of mu_rel
 
    cosTetMinNuc = cosThetaMin;
    cosTetMaxNuc = cosThetaMax;
  }
}

References cosTetMaxNuc, cosTetMinNuc, cosThetaMax, cosThetaMin, invbeta2, invbetaLab2, mass, mom2, momLab2, targetMass, tkin, and tkinLab.

Referenced by G4IonCoulombScatteringModel::ComputeCrossSectionPerAtom(), and G4IonCoulombScatteringModel::SampleSecondaries().

◆ SetupParticle()

void G4IonCoulombCrossSection::SetupParticle ( const G4ParticleDefinition * p )

inline

Definition at line 147 of file G4IonCoulombCrossSection.hh.

{
  particle = p;
  mass = particle->GetPDGMass();
  spin = particle->GetPDGSpin();
  if(0.0 != spin) { spin = 0.5; }
  G4double q = particle->GetPDGCharge()/CLHEP::eplus;
  chargeSquare = q*q;
  tkin = 0.0;
}

References chargeSquare, CLHEP::eplus, G4ParticleDefinition::GetPDGCharge(), G4ParticleDefinition::GetPDGMass(), G4ParticleDefinition::GetPDGSpin(), mass, particle, spin, and tkin.

Referenced by Initialise(), and G4IonCoulombScatteringModel::SetupParticle().

◆ SetupTarget()

void G4IonCoulombCrossSection::SetupTarget	(	G4double	Z,
		G4double	kinEnergy,
		G4int	heavycorr
	)

Definition at line 143 of file G4IonCoulombCrossSection.cc.

{
  if(Z != targetZ || e != etag) {
    etag    = e;
    targetZ = Z;
    G4int iz= G4lrint(Z);
 
    SetScreenRSquare(iz);
    screenZ = 0;
    screenZ = ScreenRSquare/mom2;
    //heavycorr = 0;
    //  G4cout<< "heavycorr "<<heavycorr<<G4endl;
 
    G4double corr=5.*twopi*Z*std::sqrt(chargeSquare*alpha2);
    corr=G4Exp(G4Log(corr)*0.04);
    screenZ *=0.5*(1.13 + corr*3.76*Z*Z*chargeSquare*invbeta2*alpha2);
    // G4cout<<" heavycorr Z e corr....2As "<< heavycorr << "\t"
    //  <<Z <<"\t"<<e/MeV <<"\t"<<screenZ<<G4endl;
      
    if(1 == iz && particle == theProton && cosTetMaxNuc < 0.0) {
      cosTetMaxNuc = 0.0;
    }
  }
}