#include <G4IonCoulombCrossSection.hh>

Public Member Functions
	G4IonCoulombCrossSection ()

virtual	~G4IonCoulombCrossSection ()

void	Initialise (const G4ParticleDefinition *, G4double cosThetaLim)

G4double	NuclearCrossSection ()

G4double	SampleCosineTheta ()

void	SetupParticle (const G4ParticleDefinition *)

void	SetupKinematic (G4double kinEnergy, G4double cut, G4int iz)

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

G4double	GetMomentum2 ()

Protected Attributes
G4double	coeff

G4double	cosThetaMin

G4double	cosThetaMax

G4double	cosTetMinNuc

G4double	cosTetMaxNuc

G4double	nucXSection

G4double	ecut

G4double	etag

const G4ParticleDefinition *	particle

G4double	chargeSquare

G4double	spin

G4double	mass

G4double	tkinLab

G4double	momLab2

G4double	invbetaLab2

G4double	tkin

G4double	mom2

G4double	invbeta2

G4double	targetZ

G4double	targetMass

G4double	screenZ

Detailed Description

Definition at line 76 of file G4IonCoulombCrossSection.hh.

Constructor & Destructor Documentation

G4IonCoulombCrossSection::G4IonCoulombCrossSection ( )

Definition at line 67 of file G4IonCoulombCrossSection.cc.

References chargeSquare, python.hepunit::classic_electr_radius, coeff, cosTetMaxNuc, cosTetMinNuc, ecut, python.hepunit::electron_mass_c2, etag, G4NistManager::Instance(), invbeta2, invbetaLab2, mass, mom2, momLab2, nucXSection, particle, G4Proton::Proton(), screenZ, spin, targetMass, targetZ, tkin, tkinLab, and python.hepunit::twopi.

                                                   :
    cosThetaMin(1.0),
    cosThetaMax(-1.0),
    alpha2(fine_structure_const*fine_structure_const)
 {
     fNistManager = G4NistManager::Instance();
         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;
     tkinLab = momLab2 = invbetaLab2=0;
         tkin = mom2 = invbeta2=0;
 
     targetZ = targetMass = screenZ =0;
         ScreenRSquare=0.;
 
     etag = ecut = 0.0;
 
 }

G4IonCoulombCrossSection::~G4IonCoulombCrossSection ( )

virtual

Definition at line 96 of file G4IonCoulombCrossSection.cc.

97 {}

Member Function Documentation

G4double G4IonCoulombCrossSection::GetMomentum2 ( )

inline

Definition at line 177 of file G4IonCoulombCrossSection.hh.

References mom2.

Referenced by G4IonCoulombScatteringModel::SampleSecondaries().

                                                       {
     return mom2;
 }

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

Definition at line 100 of file G4IonCoulombCrossSection.cc.

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

Referenced by G4IonCoulombScatteringModel::Initialise().

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

G4double G4IonCoulombCrossSection::NuclearCrossSection ( )

Definition at line 211 of file G4IonCoulombCrossSection.cc.

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

Referenced by G4IonCoulombScatteringModel::ComputeCrossSectionPerAtom().

 {
     // 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;
 }

G4double G4IonCoulombCrossSection::SampleCosineTheta ( )

Definition at line 236 of file G4IonCoulombCrossSection.cc.

References cosTetMaxNuc, cosTetMinNuc, G4UniformRand, and screenZ.

Referenced by G4IonCoulombScatteringModel::SampleSecondaries().

 {
     
     if(cosTetMaxNuc >= cosTetMinNuc) return 0.0;
 
     G4double x1 = 1. - cosTetMinNuc + screenZ;
     G4double x2 = 1. - cosTetMaxNuc + screenZ;
     G4double dx = cosTetMinNuc - cosTetMaxNuc;
     G4double /*grej,*/ z1;
 
             z1 = x1*x2/(x1 + G4UniformRand()*dx) - screenZ;
                 //grej = 1.0/(1.0 + z1);
   return z1;
 }

void G4IonCoulombCrossSection::SetupKinematic	(	G4double	kinEnergy,
		G4double	cut,
		G4int	iz
	)

Definition at line 116 of file G4IonCoulombCrossSection.cc.

References python.hepunit::amu_c2, cosTetMaxNuc, cosTetMinNuc, cosThetaMax, cosThetaMin, ecut, G4NistManager::GetAtomicMassAmu(), invbeta2, invbetaLab2, mass, mom2, momLab2, targetMass, tkin, and tkinLab.

Referenced by G4IonCoulombScatteringModel::ComputeCrossSectionPerAtom().

 {
   if(ekin != tkinLab || ecut != cut) {
 
     // 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;
 
     targetMass=fNistManager->GetAtomicMassAmu(iz)*amu_c2;
 
     // relativistic reduced mass from publucation
     // A.P. Martynenko, R.N. Faustov, Teoret. mat. Fiz. 64 (1985) 179
         
     //incident particle & target nucleus
     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;
 
   }
 
 }

void G4IonCoulombCrossSection::SetupParticle ( const G4ParticleDefinition * p )

inline

Definition at line 164 of file G4IonCoulombCrossSection.hh.

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

Referenced by Initialise().

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

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

Definition at line 154 of file G4IonCoulombCrossSection.cc.

References chargeSquare, cosTetMaxNuc, etag, invbeta2, iz, mom2, particle, screenZ, targetZ, and python.hepunit::twopi.

Referenced by G4IonCoulombScatteringModel::ComputeCrossSectionPerAtom().

 {
         if(Z != targetZ || e != etag) {
                 etag    = e;
                 targetZ = Z;
                 G4int iz= G4int(Z);
 
                 SetScreenRSquare(iz);
         screenZ =0;
             screenZ = ScreenRSquare/mom2;
 
     //  G4cout<< "heavycorr "<<heavycorr<<G4endl;
 
         if(heavycorr!=0 && particle != theProton){
             G4double corr=5.*twopi*Z*std::sqrt(chargeSquare*alpha2);
             corr=std::pow(corr,0.12);
             screenZ *=(1.13 + corr*3.76*Z*Z*chargeSquare*invbeta2*alpha2)/2.;
 //          G4cout<<" heavycorr Z e corr....2As "<< heavycorr << "\t"
 //              <<Z <<"\t"<<e/MeV <<"\t"<<screenZ<<G4endl;
 
         }else{ screenZ *=(1.13 + 3.76*Z*Z*chargeSquare*invbeta2*alpha2)/2.;
 //                        G4cout<<"  heavycorr Z e....2As "<< heavycorr << "\t"
 //              <<Z <<"\t"<< e/MeV <<"\t"  <<screenZ<<G4endl;
         }
 
                 if(1 == iz && particle == theProton && cosTetMaxNuc < 0.0) {
                         cosTetMaxNuc = 0.0;
                 }
 
         }
 }