#include <G4eBremsstrahlungModel.hh>

Inheritance diagram for G4eBremsstrahlungModel:

Public Member Functions
	G4eBremsstrahlungModel (const G4ParticleDefinition *p=0, const G4String &nam="eBrem")

virtual	~G4eBremsstrahlungModel ()

virtual void	Initialise (const G4ParticleDefinition *, const G4DataVector &)

virtual G4double	ComputeDEDXPerVolume (const G4Material , const G4ParticleDefinition , G4double kineticEnergy, G4double cutEnergy)

virtual G4double	ComputeCrossSectionPerAtom (const G4ParticleDefinition *, G4double tkin, G4double Z, G4double, G4double cut, G4double maxE=DBL_MAX)

virtual G4double	CrossSectionPerVolume (const G4Material , const G4ParticleDefinition , G4double kineticEnergy, G4double cutEnergy, G4double maxEnergy)

virtual void	SampleSecondaries (std::vector< G4DynamicParticle * > , const G4MaterialCutsCouple , const G4DynamicParticle *, G4double tmin, G4double maxEnergy)

Public Member Functions inherited from G4VEmModel
	G4VEmModel (const G4String &nam)

virtual	~G4VEmModel ()

virtual void	Initialise (const G4ParticleDefinition *, const G4DataVector &)=0

virtual void	SampleSecondaries (std::vector< G4DynamicParticle * > , const G4MaterialCutsCouple , const G4DynamicParticle *, G4double tmin=0.0, G4double tmax=DBL_MAX)=0

virtual G4double	ComputeDEDXPerVolume (const G4Material , const G4ParticleDefinition , G4double kineticEnergy, G4double cutEnergy=DBL_MAX)

virtual G4double	CrossSectionPerVolume (const G4Material , const G4ParticleDefinition , G4double kineticEnergy, G4double cutEnergy=0.0, G4double maxEnergy=DBL_MAX)

virtual G4double	ComputeCrossSectionPerAtom (const G4ParticleDefinition *, G4double kinEnergy, G4double Z, G4double A=0., G4double cutEnergy=0.0, G4double maxEnergy=DBL_MAX)

virtual G4double	ChargeSquareRatio (const G4Track &)

virtual G4double	GetChargeSquareRatio (const G4ParticleDefinition , const G4Material , G4double kineticEnergy)

virtual G4double	GetParticleCharge (const G4ParticleDefinition , const G4Material , G4double kineticEnergy)

virtual void	StartTracking (G4Track *)

virtual void	CorrectionsAlongStep (const G4MaterialCutsCouple , const G4DynamicParticle , G4double &eloss, G4double &niel, G4double length)

virtual G4double	Value (const G4MaterialCutsCouple , const G4ParticleDefinition , G4double kineticEnergy)

virtual G4double	MinPrimaryEnergy (const G4Material , const G4ParticleDefinition )

virtual void	SetupForMaterial (const G4ParticleDefinition , const G4Material , G4double kineticEnergy)

virtual void	DefineForRegion (const G4Region *)

void	InitialiseElementSelectors (const G4ParticleDefinition *, const G4DataVector &)

G4double	ComputeDEDX (const G4MaterialCutsCouple , const G4ParticleDefinition , G4double kineticEnergy, G4double cutEnergy=DBL_MAX)

G4double	CrossSection (const G4MaterialCutsCouple , const G4ParticleDefinition , G4double kineticEnergy, G4double cutEnergy=0.0, G4double maxEnergy=DBL_MAX)

G4double	ComputeMeanFreePath (const G4ParticleDefinition , G4double kineticEnergy, const G4Material , G4double cutEnergy=0.0, G4double maxEnergy=DBL_MAX)

G4double	ComputeCrossSectionPerAtom (const G4ParticleDefinition , const G4Element , G4double kinEnergy, G4double cutEnergy=0.0, G4double maxEnergy=DBL_MAX)

G4int	SelectIsotopeNumber (const G4Element *)

const G4Element *	SelectRandomAtom (const G4MaterialCutsCouple , const G4ParticleDefinition , G4double kineticEnergy, G4double cutEnergy=0.0, G4double maxEnergy=DBL_MAX)

const G4Element *	SelectRandomAtom (const G4Material , const G4ParticleDefinition , G4double kineticEnergy, G4double cutEnergy=0.0, G4double maxEnergy=DBL_MAX)

void	SetParticleChange (G4VParticleChange , G4VEmFluctuationModel f=0)

void	SetCrossSectionTable (G4PhysicsTable *)

G4PhysicsTable *	GetCrossSectionTable ()

G4VEmFluctuationModel *	GetModelOfFluctuations ()

G4VEmAngularDistribution *	GetAngularDistribution ()

void	SetAngularDistribution (G4VEmAngularDistribution *)

G4double	HighEnergyLimit () const

G4double	LowEnergyLimit () const

G4double	HighEnergyActivationLimit () const

G4double	LowEnergyActivationLimit () const

G4double	PolarAngleLimit () const

G4double	SecondaryThreshold () const

G4bool	LPMFlag () const

G4bool	DeexcitationFlag () const

G4bool	ForceBuildTableFlag () const

void	SetHighEnergyLimit (G4double)

void	SetLowEnergyLimit (G4double)

void	SetActivationHighEnergyLimit (G4double)

void	SetActivationLowEnergyLimit (G4double)

G4bool	IsActive (G4double kinEnergy)

void	SetPolarAngleLimit (G4double)

void	SetSecondaryThreshold (G4double)

void	SetLPMFlag (G4bool val)

void	SetDeexcitationFlag (G4bool val)

void	ForceBuildTable (G4bool val)

G4double	MaxSecondaryKinEnergy (const G4DynamicParticle *dynParticle)

const G4String &	GetName () const

void	SetCurrentCouple (const G4MaterialCutsCouple *)

const G4Element *	GetCurrentElement () const

Protected Member Functions
const G4Element *	SelectRandomAtom (const G4MaterialCutsCouple *couple)

Protected Member Functions inherited from G4VEmModel
G4ParticleChangeForLoss *	GetParticleChangeForLoss ()

G4ParticleChangeForGamma *	GetParticleChangeForGamma ()

virtual G4double	MaxSecondaryEnergy (const G4ParticleDefinition *, G4double kineticEnergy)

const G4MaterialCutsCouple *	CurrentCouple () const

void	SetCurrentElement (const G4Element *)

Protected Attributes
const G4ParticleDefinition *	particle

G4ParticleDefinition *	theGamma

G4ParticleChangeForLoss *	fParticleChange

G4bool	isElectron

Protected Attributes inherited from G4VEmModel
G4VParticleChange *	pParticleChange

G4PhysicsTable *	xSectionTable

const std::vector< G4double > *	theDensityFactor

const std::vector< G4int > *	theDensityIdx

Detailed Description

Definition at line 64 of file G4eBremsstrahlungModel.hh.

Constructor & Destructor Documentation

◆ G4eBremsstrahlungModel()

G4eBremsstrahlungModel::G4eBremsstrahlungModel	(	const G4ParticleDefinition *	p = `0`,
		const G4String &	nam = `"eBrem"`
	)

Definition at line 85 of file G4eBremsstrahlungModel.cc.

  : G4VEmModel(nam),
    particle(0),
    isElectron(true),
    probsup(1.0),
    MigdalConstant(classic_electr_radius*electron_Compton_length*electron_Compton_length*4.0*pi),
    LPMconstant(fine_structure_const*electron_mass_c2*electron_mass_c2/(4.*pi*hbarc)),
    isInitialised(false)
{
  if(p) { SetParticle(p); }
  theGamma = G4Gamma::Gamma();
  SetAngularDistribution(new G4ModifiedTsai());
  highKinEnergy = HighEnergyLimit();
  lowKinEnergy  = LowEnergyLimit();
  fParticleChange = 0;
}

◆ ~G4eBremsstrahlungModel()

G4eBremsstrahlungModel::~G4eBremsstrahlungModel ( )

virtual

Definition at line 105 of file G4eBremsstrahlungModel.cc.

{
  size_t n = partialSumSigma.size();
  if(n > 0) {
    for(size_t i=0; i<n; i++) {
      delete partialSumSigma[i];
    }
  }
}

Member Function Documentation

◆ ComputeCrossSectionPerAtom()

G4double G4eBremsstrahlungModel::ComputeCrossSectionPerAtom	(	const G4ParticleDefinition *	,
		G4double	tkin,
		G4double	Z,
		G4double	,
		G4double	cut,
		G4double	maxE = `DBL_MAX`
	)

virtual

Reimplemented from G4VEmModel.

Definition at line 484 of file G4eBremsstrahlungModel.cc.

{
  G4double cross = 0.0 ;
  if ( kineticEnergy < keV || kineticEnergy < cut) { return cross; }
 
  static const G4double ksi=2.0, alfa=1.00;
  static const G4double csigh = 0.127, csiglow = 0.25, asiglow = 0.020*MeV ;
  static const G4double Tlim = 10.*MeV ;
 
  static const G4double xlim = 1.2 ;
  static const G4int NZ = 8 ;
  static const G4int Nsig = 11 ;
  static const G4double ZZ[NZ] =
        {2.,4.,6.,14.,26.,50.,82.,92.} ;
  static const G4double coefsig[NZ][Nsig] = {
  // Z=2
  { 0.4638,        0.37748,        0.32249,      -0.060362,      -0.065004,
   -0.033457,      -0.004583,       0.011954,      0.0030404,     -0.0010077,
   -0.00028131},
 
  // Z=4
  { 0.50008,        0.33483,        0.34364,      -0.086262,      -0.055361,
   -0.028168,     -0.0056172,       0.011129,      0.0027528,    -0.00092265,
   -0.00024348},
 
  // Z=6
  { 0.51587,        0.31095,        0.34996,       -0.11623,      -0.056167,
   -0.0087154,     0.00053943,      0.0054092,     0.00077685,    -0.00039635,
   -6.7818e-05},
 
  // Z=14
  { 0.55058,        0.25629,        0.35854,      -0.080656,      -0.054308,
   -0.049933,    -0.00064246,       0.016597,      0.0021789,      -0.001327,
   -0.00025983},
 
  // Z=26
  { 0.5791,        0.26152,        0.38953,       -0.17104,      -0.099172,
    0.024596,       0.023718,     -0.0039205,     -0.0036658,     0.00041749,
    0.00023408},
 
  // Z=50
  { 0.62085,        0.27045,        0.39073,       -0.37916,       -0.18878,
    0.23905,       0.095028,      -0.068744,      -0.023809,      0.0062408,
    0.0020407},
 
  // Z=82
  { 0.66053,        0.24513,        0.35404,       -0.47275,       -0.22837,
    0.35647,        0.13203,        -0.1049,      -0.034851,      0.0095046,
    0.0030535},
 
  // Z=92
  { 0.67143,        0.23079,        0.32256,       -0.46248,       -0.20013,
    0.3506,        0.11779,        -0.1024,      -0.032013,      0.0092279,
    0.0028592}
 
    } ;
 
  G4int iz = 0 ;
  G4double delz = 1.e6 ;
  for (G4int ii=0; ii<NZ; ii++)
  {
    G4double absdelz = std::abs(Z-ZZ[ii]); 
    if(absdelz < delz)
    {
      iz = ii ;
      delz = absdelz;
    }
  }
 
  G4double xx = log10(kineticEnergy/MeV);
  G4double fs = 1. ;
 
  if (xx <= xlim) {
 
    fs = coefsig[iz][Nsig-1] ;
    for (G4int j=Nsig-2; j>=0; j--) {
 
      fs = fs*xx+coefsig[iz][j] ;
    }
    if(fs < 0.) { fs = 0.; }
  }
 
  cross = Z*(Z+ksi)*(1.-csigh*exp(log(Z)/4.))*pow(log(kineticEnergy/cut),alfa);
 
  if (kineticEnergy <= Tlim)
     cross *= exp(csiglow*log(Tlim/kineticEnergy))
              *(1.+asiglow/(sqrt(Z)*kineticEnergy));
 
  if (!isElectron)
     cross *= PositronCorrFactorSigma(Z, kineticEnergy, cut);
 
  cross *= fs/Avogadro ;
 
  if (cross < 0.) { cross = 0.; }
  return cross;
}

Referenced by CrossSectionPerVolume().

◆ ComputeDEDXPerVolume()

G4double G4eBremsstrahlungModel::ComputeDEDXPerVolume	(	const G4Material *	material,
		const G4ParticleDefinition *	p,
		G4double	kineticEnergy,
		G4double	cutEnergy
	)

virtual

Reimplemented from G4VEmModel.

Definition at line 166 of file G4eBremsstrahlungModel.cc.

{
  if(!particle) { SetParticle(p); }
  if(kineticEnergy < lowKinEnergy) { return 0.0; }
 
  const G4double thigh = 100.*GeV;
 
  G4double cut = std::min(cutEnergy, kineticEnergy);
 
  G4double rate, loss;
  const G4double factorHigh = 36./(1450.*GeV);
  const G4double coef1 = -0.5;
  const G4double coef2 = 2./9.;
 
  const G4ElementVector* theElementVector = material->GetElementVector();
  const G4double* theAtomicNumDensityVector = material->GetAtomicNumDensityVector();
 
  G4double totalEnergy = kineticEnergy + electron_mass_c2;
  G4double dedx = 0.0;
 
  //  loop for elements in the material
  for (size_t i=0; i<material->GetNumberOfElements(); i++) {
 
    G4double Z     = (*theElementVector)[i]->GetZ();
    G4double natom = theAtomicNumDensityVector[i];
 
    // loss for MinKinEnergy<KineticEnergy<=100 GeV
    if (kineticEnergy <= thigh) {
 
      //      x = log(totalEnergy/electron_mass_c2);
      loss = ComputeBremLoss(Z, kineticEnergy, cut) ;
      if (!isElectron) loss *= PositronCorrFactorLoss(Z, kineticEnergy, cut);
 
    // extrapolation for KineticEnergy>100 GeV
    } else {
 
      //      G4double xhigh = log(thigh/electron_mass_c2);
      G4double cuthigh = thigh*0.5;
 
      if (cut < thigh) {
 
        loss = ComputeBremLoss(Z, thigh, cut) ;
        if (!isElectron) loss *= PositronCorrFactorLoss(Z, thigh, cut) ;
        rate = cut/totalEnergy;
        loss *= (1. + coef1*rate + coef2*rate*rate);
        rate = cut/thigh;
        loss /= (1.+coef1*rate+coef2*rate*rate);
 
      } else {
 
        loss = ComputeBremLoss(Z, thigh, cuthigh) ;
        if (!isElectron) loss *= PositronCorrFactorLoss(Z, thigh, cuthigh) ;
        rate = cut/totalEnergy;
        loss *= (1. + coef1*rate + coef2*rate*rate);
        loss *= cut*factorHigh;
      }
    }
    loss *= natom;
 
    G4double kp2 = MigdalConstant*totalEnergy*totalEnergy
                 * (material->GetElectronDensity()) ;
 
    // now compute the correction due to the supression(s)
    G4double kmin = 1.*eV;
    G4double kmax = cut;
 
    if (kmax > kmin) {
 
      G4double floss = 0.;
      G4int nmax = 100;
 
      G4double vmin=log(kmin);
      G4double vmax=log(kmax) ;
      G4int nn = (G4int)(nmax*(vmax-vmin)/(log(highKinEnergy)-vmin)) ;
      G4double u,fac,c,v,dv ;
      if(nn > 0) {
 
        dv = (vmax-vmin)/nn ;
        v  = vmin-dv ;
 
        for(G4int n=0; n<=nn; n++) {
 
          v += dv;
          u = exp(v);
          fac = u*SupressionFunction(material,kineticEnergy,u);
      fac *= probsup*(u*u/(u*u+kp2))+1.-probsup;
          if ((n==0)||(n==nn)) c=0.5;
          else                 c=1. ;
          fac   *= c ;
          floss += fac ;
        }
        floss *=dv/(kmax-kmin);
 
      } else {
        floss = 1.;
      }
      if(floss > 1.) floss = 1.;
      // correct the loss
      loss *= floss;
    }
    dedx += loss;
  }
  if(dedx < 0.) { dedx = 0.; }
  return dedx;
}

◆ CrossSectionPerVolume()

G4double G4eBremsstrahlungModel::CrossSectionPerVolume	(	const G4Material *	material,
		const G4ParticleDefinition *	p,
		G4double	kineticEnergy,
		G4double	cutEnergy,
		G4double	maxEnergy
	)

virtual

Reimplemented from G4VEmModel.

Definition at line 406 of file G4eBremsstrahlungModel.cc.

{
  if(!particle) { SetParticle(p); }
  G4double cross = 0.0;
  G4double tmax = min(maxEnergy, kineticEnergy);
  G4double cut  = min(cutEnergy, kineticEnergy);
  if(cut >= tmax) { return cross; }
 
  const G4ElementVector* theElementVector = material->GetElementVector();
  const G4double* theAtomNumDensityVector = material->GetAtomicNumDensityVector();
  G4double dum=0.;
  
  for (size_t i=0; i<material->GetNumberOfElements(); i++) {
 
    cross += theAtomNumDensityVector[i] * ComputeCrossSectionPerAtom(p,
                      kineticEnergy, (*theElementVector)[i]->GetZ(), dum, cut);
    if (tmax < kineticEnergy) {
      cross -= theAtomNumDensityVector[i] * ComputeCrossSectionPerAtom(p,
                     kineticEnergy, (*theElementVector)[i]->GetZ(), dum, tmax);
    }
  }
 
  // now compute the correction due to the supression(s)
 
  G4double kmax = tmax;
  G4double kmin = cut;
 
  G4double totalEnergy = kineticEnergy+electron_mass_c2 ;
  G4double kp2 = MigdalConstant*totalEnergy*totalEnergy
                                             *(material->GetElectronDensity());
 
  G4double fsig = 0.;
  G4int nmax = 100;
  G4double vmin=log(kmin);
  G4double vmax=log(kmax) ;
  G4int nn = (G4int)(nmax*(vmax-vmin)/(log(highKinEnergy)-vmin));
  G4double u,fac,c,v,dv,y ;
  if(nn > 0) {
 
      dv = (vmax-vmin)/nn ;
      v  = vmin-dv ;
      for(G4int n=0; n<=nn; n++) {
 
        v += dv;  
        u = exp(v);              
        fac = SupressionFunction(material, kineticEnergy, u);
        y = u/kmax;
        fac *= (4.-4.*y+3.*y*y)/3.;
        fac *= probsup*(u*u/(u*u+kp2))+1.-probsup;
 
        if ((n==0)||(n==nn)) c=0.5;
        else                 c=1. ;
 
        fac  *= c;
        fsig += fac;
      }
      y = kmin/kmax ;
      fsig *=dv/(-4.*log(y)/3.-4.*(1.-y)/3.+0.5*(1.-y*y));
 
  } else {
 
      fsig = 1.;
  }
  if (fsig > 1.) fsig = 1.;
 
  // correct the cross section
  cross *= fsig;
 
  return cross;
}

◆ Initialise()

void G4eBremsstrahlungModel::Initialise	(	const G4ParticleDefinition *	p,
		const G4DataVector &	cuts
	)

virtual

Implements G4VEmModel.

Reimplemented in G4ePolarizedBremsstrahlungModel.

Definition at line 126 of file G4eBremsstrahlungModel.cc.

{
  if(p) { SetParticle(p); }
  highKinEnergy = HighEnergyLimit();
  lowKinEnergy  = LowEnergyLimit();
  const G4ProductionCutsTable* theCoupleTable=
        G4ProductionCutsTable::GetProductionCutsTable();
 
  if(theCoupleTable) {
    G4int numOfCouples = theCoupleTable->GetTableSize();
 
    G4int nn = partialSumSigma.size();
    G4int nc = cuts.size();
    if(nn > 0) {
      for (G4int ii=0; ii<nn; ii++){
    G4DataVector* a=partialSumSigma[ii];
    if ( a )  delete a;
      }
      partialSumSigma.clear();
    }
    if(numOfCouples>0) {
      for (G4int i=0; i<numOfCouples; i++) {
        G4double cute   = DBL_MAX;
        if(i < nc) cute = cuts[i];
    const G4MaterialCutsCouple* couple = theCoupleTable->GetMaterialCutsCouple(i);
    const G4Material* material = couple->GetMaterial();
    G4DataVector* dv = ComputePartialSumSigma(material, 0.5*highKinEnergy,
                             std::min(cute, 0.25*highKinEnergy));
    partialSumSigma.push_back(dv);
      }
    }
  }
  if(isInitialised) return;
  fParticleChange = GetParticleChangeForLoss();
  isInitialised = true;
}

Referenced by G4ePolarizedBremsstrahlungModel::Initialise().

◆ SampleSecondaries()

void G4eBremsstrahlungModel::SampleSecondaries	(	std::vector< G4DynamicParticle * > *	vdp,
		const G4MaterialCutsCouple *	couple,
		const G4DynamicParticle *	dp,
		G4double	tmin,
		G4double	maxEnergy
	)

virtual

Implements G4VEmModel.

Reimplemented in G4ePolarizedBremsstrahlungModel.

Definition at line 643 of file G4eBremsstrahlungModel.cc.

{
  G4double kineticEnergy = dp->GetKineticEnergy();
  G4double tmax = min(maxEnergy, kineticEnergy);
  if(tmin >= tmax) { return; }
 
//
// GEANT4 internal units.
//
  static const G4double
     ah10 = 4.67733E+00, ah11 =-6.19012E-01, ah12 = 2.02225E-02,
     ah20 =-7.34101E+00, ah21 = 1.00462E+00, ah22 =-3.20985E-02,
     ah30 = 2.93119E+00, ah31 =-4.03761E-01, ah32 = 1.25153E-02;
 
  static const G4double
     bh10 = 4.23071E+00, bh11 =-6.10995E-01, bh12 = 1.95531E-02,
     bh20 =-7.12527E+00, bh21 = 9.69160E-01, bh22 =-2.74255E-02,
     bh30 = 2.69925E+00, bh31 =-3.63283E-01, bh32 = 9.55316E-03;
 
  static const G4double
     al00 =-2.05398E+00, al01 = 2.38815E-02, al02 = 5.25483E-04,
     al10 =-7.69748E-02, al11 =-6.91499E-02, al12 = 2.22453E-03,
     al20 = 4.06463E-02, al21 =-1.01281E-02, al22 = 3.40919E-04;
 
  static const G4double
     bl00 = 1.04133E+00, bl01 =-9.43291E-03, bl02 =-4.54758E-04,
     bl10 = 1.19253E-01, bl11 = 4.07467E-02, bl12 =-1.30718E-03,
     bl20 =-1.59391E-02, bl21 = 7.27752E-03, bl22 =-1.94405E-04;
 
  static const G4double tlow = 1.*MeV;
 
  G4double gammaEnergy;
  G4bool LPMOK = false;
  const G4Material* material = couple->GetMaterial();
 
  // select randomly one element constituing the material
  const G4Element* anElement = SelectRandomAtom(couple);
 
  // Extract Z factors for this Element
  G4double lnZ = 3.*(anElement->GetIonisation()->GetlogZ3());
  G4double FZ = lnZ* (4.- 0.55*lnZ);
  G4double ZZ = anElement->GetIonisation()->GetZZ3();
 
  // limits of the energy sampling
  G4double totalEnergy = kineticEnergy + electron_mass_c2;
 
  G4double xmin     = tmin/kineticEnergy;
  G4double xmax     = tmax/kineticEnergy;
  G4double kappa    = 0.0;
  if(xmax >= 1.) { xmax = 1.; }
  else   { kappa    = log(xmax)/log(xmin); }
  G4double epsilmin = tmin/totalEnergy;
  G4double epsilmax = tmax/totalEnergy;
 
  // Migdal factor
  G4double MigdalFactor = (material->GetElectronDensity())*MigdalConstant
                        / (epsilmax*epsilmax);
 
  G4double x, epsil, greject, migdal, grejmax, q;
  G4double U  = log(kineticEnergy/electron_mass_c2);
  G4double U2 = U*U;
 
  // precalculated parameters
  G4double ah, bh;
  G4double screenfac = 0.0;
 
  if (kineticEnergy > tlow) {
       
    G4double ah1 = ah10 + ZZ* (ah11 + ZZ* ah12);
    G4double ah2 = ah20 + ZZ* (ah21 + ZZ* ah22);
    G4double ah3 = ah30 + ZZ* (ah31 + ZZ* ah32);
 
    G4double bh1 = bh10 + ZZ* (bh11 + ZZ* bh12);
    G4double bh2 = bh20 + ZZ* (bh21 + ZZ* bh22);
    G4double bh3 = bh30 + ZZ* (bh31 + ZZ* bh32);
 
    ah = 1.   + (ah1*U2 + ah2*U + ah3) / (U2*U);
    bh = 0.75 + (bh1*U2 + bh2*U + bh3) / (U2*U);
 
    // limit of the screening variable
    screenfac =
      136.*electron_mass_c2/((anElement->GetIonisation()->GetZ3())*totalEnergy);
    G4double screenmin = screenfac*epsilmin/(1.-epsilmin);
 
    // Compute the maximum of the rejection function
    G4double F1 = max(ScreenFunction1(screenmin) - FZ ,0.);
    G4double F2 = max(ScreenFunction2(screenmin) - FZ ,0.);
    grejmax = (F1 - epsilmin* (F1*ah - bh*epsilmin*F2))/(42.392 - FZ);
 
  } else {  
 
    G4double al0 = al00 + ZZ* (al01 + ZZ* al02);
    G4double al1 = al10 + ZZ* (al11 + ZZ* al12);
    G4double al2 = al20 + ZZ* (al21 + ZZ* al22);
 
    G4double bl0 = bl00 + ZZ* (bl01 + ZZ* bl02);
    G4double bl1 = bl10 + ZZ* (bl11 + ZZ* bl12);
    G4double bl2 = bl20 + ZZ* (bl21 + ZZ* bl22);
 
    ah = al0 + al1*U + al2*U2;
    bh = bl0 + bl1*U + bl2*U2;
 
    // Compute the maximum of the rejection function
    grejmax = max(1. + xmin* (ah + bh*xmin), 1.+ah+bh);
    G4double xm = -ah/(2.*bh);
    if ( xmin < xm && xm < xmax) grejmax = max(grejmax, 1.+ xm* (ah + bh*xm));
  }
 
  //
  //  sample the energy rate of the emitted gamma for e- kin energy > 1 MeV
  //
 
  do {
    if (kineticEnergy > tlow) {
      do {
        q = G4UniformRand();
        x = pow(xmin, q + kappa*(1.0 - q));
        epsil = x*kineticEnergy/totalEnergy;
        G4double screenvar = screenfac*epsil/(1.0-epsil);
        G4double F1 = max(ScreenFunction1(screenvar) - FZ ,0.);
        G4double F2 = max(ScreenFunction2(screenvar) - FZ ,0.);
        migdal = (1. + MigdalFactor)/(1. + MigdalFactor/(x*x));
        greject = migdal*(F1 - epsil* (ah*F1 - bh*epsil*F2))/(42.392 - FZ);
    /*
    if ( greject > grejmax ) {
            G4cout << "### G4eBremsstrahlungModel Warning: Majoranta exceeded! "
                   << greject << " > " << grejmax
                   << " x= " << x 
           << " e= " << kineticEnergy
                   << G4endl;
    }
    */  
      } while( greject < G4UniformRand()*grejmax );
 
    } else {  
 
      do {
        q = G4UniformRand();
        x = pow(xmin, q + kappa*(1.0 - q));
        migdal = (1. + MigdalFactor)/(1. + MigdalFactor/(x*x));  
        greject = migdal*(1. + x* (ah + bh*x));
    /*
    if ( greject > grejmax ) {
      G4cout << "### G4eBremsstrahlungModel Warning: Majoranta exceeded! " 
                 << greject << " > " << grejmax 
                 << " x= " << x 
         << " e= " << kineticEnergy
                 << G4endl;
    }
    */
      } while( greject < G4UniformRand()*grejmax );
    }
    gammaEnergy = x*kineticEnergy; 
 
    if (LPMFlag()) {
     // take into account the supression due to the LPM effect
      if (G4UniformRand() <= SupressionFunction(material,kineticEnergy,
                                                           gammaEnergy))
        LPMOK = true;
      }
    else LPMOK = true;
 
  } while (!LPMOK);
 
  //
  // angles of the emitted gamma. ( Z - axis along the parent particle)
  // use general interface
  //
 
  G4ThreeVector gammaDirection = 
    GetAngularDistribution()->SampleDirection(dp, totalEnergy-gammaEnergy,
                          G4lrint(anElement->GetZ()), 
                          couple->GetMaterial());
 
  // create G4DynamicParticle object for the Gamma
  G4DynamicParticle* gamma = new G4DynamicParticle(theGamma,gammaDirection,
                           gammaEnergy);
  vdp->push_back(gamma);
  
  G4double totMomentum = sqrt(kineticEnergy*(totalEnergy + electron_mass_c2));
 
  G4ThreeVector direction = (totMomentum*dp->GetMomentumDirection()
                 - gammaEnergy*gammaDirection).unit();
 
  // energy of primary
  G4double finalE = kineticEnergy - gammaEnergy;
 
  // stop tracking and create new secondary instead of primary
  if(gammaEnergy > SecondaryThreshold()) {
    fParticleChange->ProposeTrackStatus(fStopAndKill);
    fParticleChange->SetProposedKineticEnergy(0.0);
    G4DynamicParticle* el = 
      new G4DynamicParticle(const_cast<G4ParticleDefinition*>(particle),
                direction, finalE);
    vdp->push_back(el);
 
    // continue tracking
  } else {
    fParticleChange->SetProposedMomentumDirection(direction);
    fParticleChange->SetProposedKineticEnergy(finalE);
  }
}

Referenced by G4ePolarizedBremsstrahlungModel::SampleSecondaries().

◆ SelectRandomAtom()

const G4Element * G4eBremsstrahlungModel::SelectRandomAtom ( const G4MaterialCutsCouple * couple )

protected

Definition at line 865 of file G4eBremsstrahlungModel.cc.

{
  // select randomly 1 element within the material
 
  const G4Material* material = couple->GetMaterial();
  G4int nElements = material->GetNumberOfElements();
  const G4ElementVector* theElementVector = material->GetElementVector();
 
  const G4Element* elm = 0;
 
  if(1 < nElements) {
 
    --nElements; 
    G4DataVector* dv = partialSumSigma[couple->GetIndex()];
    G4double rval = G4UniformRand()*((*dv)[nElements]);
 
    elm = (*theElementVector)[nElements];
    for (G4int i=0; i<nElements; ++i) {
      if (rval <= (*dv)[i]) {
    elm = (*theElementVector)[i];
    break;
      }
    }
  } else { elm = (*theElementVector)[0]; }
 
  SetCurrentElement(elm);
  return elm;
}

Referenced by SampleSecondaries().

Member Data Documentation

◆ fParticleChange

G4ParticleChangeForLoss* G4eBremsstrahlungModel::fParticleChange

protected

Definition at line 131 of file G4eBremsstrahlungModel.hh.

Referenced by G4eBremsstrahlungModel(), Initialise(), G4ePolarizedBremsstrahlungModel::SampleSecondaries(), and SampleSecondaries().

◆ isElectron

G4bool G4eBremsstrahlungModel::isElectron

protected

Definition at line 133 of file G4eBremsstrahlungModel.hh.

Referenced by ComputeCrossSectionPerAtom(), and ComputeDEDXPerVolume().

◆ particle

const G4ParticleDefinition* G4eBremsstrahlungModel::particle

protected

Definition at line 129 of file G4eBremsstrahlungModel.hh.

Referenced by ComputeDEDXPerVolume(), CrossSectionPerVolume(), and SampleSecondaries().

◆ theGamma

G4ParticleDefinition* G4eBremsstrahlungModel::theGamma

protected

Definition at line 130 of file G4eBremsstrahlungModel.hh.

Referenced by G4eBremsstrahlungModel(), and SampleSecondaries().

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

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ G4eBremsstrahlungModel()

◆ ~G4eBremsstrahlungModel()

Member Function Documentation

◆ ComputeCrossSectionPerAtom()

◆ ComputeDEDXPerVolume()

◆ CrossSectionPerVolume()

◆ Initialise()

◆ SampleSecondaries()

◆ SelectRandomAtom()

Member Data Documentation

◆ fParticleChange

◆ isElectron

◆ particle

◆ theGamma