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Public Member Functions
G4BetheHeitlerModel Class Reference

#include <G4BetheHeitlerModel.hh>

Inheritance diagram for G4BetheHeitlerModel:
G4VEmModel G4PolarizedGammaConversionModel

Public Member Functions

 G4BetheHeitlerModel (const G4ParticleDefinition *p=0, const G4String &nam="BetheHeitler")
 
virtual ~G4BetheHeitlerModel ()
 
virtual void Initialise (const G4ParticleDefinition *, const G4DataVector &)
 
virtual void InitialiseLocal (const G4ParticleDefinition *, G4VEmModel *masterModel)
 
virtual G4double ComputeCrossSectionPerAtom (const G4ParticleDefinition *, G4double kinEnergy, G4double Z, G4double A=0., G4double cut=0., G4double emax=DBL_MAX)
 
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 InitialiseForMaterial (const G4ParticleDefinition *, const G4Material *)
 
virtual void InitialiseForElement (const G4ParticleDefinition *, G4int Z)
 
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 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 *, G4double cut=0.0)
 
virtual G4double MinEnergyCut (const G4ParticleDefinition *, const G4MaterialCutsCouple *)
 
virtual void SetupForMaterial (const G4ParticleDefinition *, const G4Material *, G4double kineticEnergy)
 
virtual void DefineForRegion (const G4Region *)
 
void InitialiseElementSelectors (const G4ParticleDefinition *, const G4DataVector &)
 
std::vector
< G4EmElementSelector * > * 		GetElementSelectors ()
 
void SetElementSelectors (std::vector< G4EmElementSelector * > *)
 
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)
 
G4int SelectRandomAtomNumber (const G4Material *)
 
void SetParticleChange (G4VParticleChange *, G4VEmFluctuationModel *f=0)
 
void SetCrossSectionTable (G4PhysicsTable *, G4bool isLocal)
 
G4ElementData * GetElementData ()
 
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
 
G4bool UseAngularGeneratorFlag () const
 
void SetAngularGeneratorFlag (G4bool)
 
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 SetForceBuildTable (G4bool val)
 
void SetMasterThread (G4bool val)
 
G4bool IsMaster () const
 
G4double MaxSecondaryKinEnergy (const G4DynamicParticle *dynParticle)
 
const G4String & GetName () const
 
void SetCurrentCouple (const G4MaterialCutsCouple *)
 
const G4Element * GetCurrentElement () const
 

Additional Inherited Members

- 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 inherited from G4VEmModel
G4ElementData * fElementData
 
G4VParticleChange * pParticleChange
 
G4PhysicsTable * xSectionTable
 
const std::vector< G4double > * theDensityFactor
 
const std::vector< G4int > * theDensityIdx
 
size_t idxTable
 

Detailed Description

Definition at line 60 of file G4BetheHeitlerModel.hh.

Constructor & Destructor Documentation

G4BetheHeitlerModel::G4BetheHeitlerModel ( const G4ParticleDefinition *  p = 0,
const G4String &  nam = "BetheHeitler" 
)

Definition at line 85 of file G4BetheHeitlerModel.cc.

References G4Electron::Electron(), G4Gamma::Gamma(), G4Pow::GetInstance(), and G4Positron::Positron().

87  : G4VEmModel(nam)
88 {
89  fParticleChange = 0;
90  theGamma = G4Gamma::Gamma();
91  thePositron = G4Positron::Positron();
92  theElectron = G4Electron::Electron();
93  g4pow = G4Pow::GetInstance();
94 }
G4Pow::GetInstance
static G4Pow * GetInstance()
Definition: G4Pow.cc:53
G4VEmModel::G4VEmModel
G4VEmModel(const G4String &nam)
Definition: G4VEmModel.cc:65
G4Gamma::Gamma
static G4Gamma * Gamma()
Definition: G4Gamma.cc:86
G4Positron::Positron
static G4Positron * Positron()
Definition: G4Positron.cc:94
G4Electron::Electron
static G4Electron * Electron()
Definition: G4Electron.cc:94
G4BetheHeitlerModel::~G4BetheHeitlerModel ( )
virtual

Definition at line 98 of file G4BetheHeitlerModel.cc.

99 {}

Member Function Documentation

G4double G4BetheHeitlerModel::ComputeCrossSectionPerAtom ( const G4ParticleDefinition *  ,
G4double  kinEnergy,
G4double  Z,
G4double  A = 0.,
G4double  cut = 0.,
G4double  emax = DBL_MAX 
)
virtual

Reimplemented from G4VEmModel.

Definition at line 121 of file G4BetheHeitlerModel.cc.

References python.hepunit::electron_mass_c2, and G4Log().

130 {
131  G4double xSection = 0.0 ;
132  if ( Z < 0.9 || GammaEnergy <= 2.0*electron_mass_c2 ) { return xSection; }
133 
134 
135  G4double GammaEnergySave = GammaEnergy;
136  if (GammaEnergy < GammaEnergyLimit) { GammaEnergy = GammaEnergyLimit; }
137 
138  G4double X=G4Log(GammaEnergy/electron_mass_c2), X2=X*X, X3=X2*X, X4=X3*X, X5=X4*X;
139 
140  G4double F1 = a0 + a1*X + a2*X2 + a3*X3 + a4*X4 + a5*X5,
141  F2 = b0 + b1*X + b2*X2 + b3*X3 + b4*X4 + b5*X5,
142  F3 = c0 + c1*X + c2*X2 + c3*X3 + c4*X4 + c5*X5;
143 
144  xSection = (Z + 1.)*(F1*Z + F2*Z*Z + F3);
145 
146  if (GammaEnergySave < GammaEnergyLimit) {
147 
148  X = (GammaEnergySave - 2.*electron_mass_c2)
149  / (GammaEnergyLimit - 2.*electron_mass_c2);
150  xSection *= X*X;
151  }
152 
153  if (xSection < 0.) { xSection = 0.; }
154  return xSection;
155 }
python.hepunit.electron_mass_c2
float electron_mass_c2
Definition: hepunit.py:274
G4Log
G4double G4Log(G4double x)
Definition: G4Log.hh:227
G4double
double G4double
Definition: G4Types.hh:76
plottest35.c1
tuple c1
Definition: plottest35.py:14
void G4BetheHeitlerModel::Initialise ( const G4ParticleDefinition *  p,
const G4DataVector &  cuts 
)
virtual

Implements G4VEmModel.

Reimplemented in G4PolarizedGammaConversionModel.

Definition at line 103 of file G4BetheHeitlerModel.cc.

References G4VEmModel::GetParticleChangeForGamma(), G4VEmModel::InitialiseElementSelectors(), and G4VEmModel::IsMaster().

Referenced by G4PolarizedGammaConversionModel::Initialise().

105 {
106  if(!fParticleChange) { fParticleChange = GetParticleChangeForGamma(); }
107  if(IsMaster()) { InitialiseElementSelectors(p, cuts); }
108 }
G4VEmModel::InitialiseElementSelectors
void InitialiseElementSelectors(const G4ParticleDefinition *, const G4DataVector &)
Definition: G4VEmModel.cc:135
G4VEmModel::IsMaster
G4bool IsMaster() const
Definition: G4VEmModel.hh:676
G4VEmModel::GetParticleChangeForGamma
G4ParticleChangeForGamma * GetParticleChangeForGamma()
Definition: G4VEmModel.cc:121
void G4BetheHeitlerModel::InitialiseLocal ( const G4ParticleDefinition *  ,
G4VEmModel *  masterModel 
)
virtual

Reimplemented from G4VEmModel.

Definition at line 112 of file G4BetheHeitlerModel.cc.

References G4VEmModel::GetElementSelectors(), and G4VEmModel::SetElementSelectors().

114 {
115  SetElementSelectors(masterModel->GetElementSelectors());
116 }
G4VEmModel::GetElementSelectors
std::vector< G4EmElementSelector * > * GetElementSelectors()
Definition: G4VEmModel.hh:760
G4VEmModel::SetElementSelectors
void SetElementSelectors(std::vector< G4EmElementSelector * > *)
Definition: G4VEmModel.hh:768
void G4BetheHeitlerModel::SampleSecondaries ( std::vector< G4DynamicParticle * > *  fvect,
const G4MaterialCutsCouple *  couple,
const G4DynamicParticle *  aDynamicGamma,
G4double  tmin,
G4double  maxEnergy 
)
virtual

Implements G4VEmModel.

Reimplemented in G4PolarizedGammaConversionModel.

Definition at line 159 of file G4BetheHeitlerModel.cc.

References G4Pow::A13(), python.hepunit::electron_mass_c2, F10, F20, fStopAndKill, G4Log(), G4UniformRand, G4Element::GetfCoulomb(), G4Element::GetIonisation(), G4DynamicParticle::GetKineticEnergy(), G4IonisParamElm::GetlogZ3(), G4MaterialCutsCouple::GetMaterial(), G4DynamicParticle::GetMomentumDirection(), G4IonisParamElm::GetZ3(), G4INCL::Math::max(), python.hepunit::MeV, G4INCL::Math::min(), G4VParticleChange::ProposeTrackStatus(), CLHEP::Hep3Vector::rotateUz(), G4VEmModel::SelectRandomAtom(), G4ParticleChangeForGamma::SetProposedKineticEnergy(), and python.hepunit::twopi.

Referenced by G4PolarizedGammaConversionModel::SampleSecondaries().

176 {
177  const G4Material* aMaterial = couple->GetMaterial();
178 
179  G4double GammaEnergy = aDynamicGamma->GetKineticEnergy();
180  G4ParticleMomentum GammaDirection = aDynamicGamma->GetMomentumDirection();
181 
182  G4double epsil ;
183  G4double epsil0 = electron_mass_c2/GammaEnergy ;
184  if(epsil0 > 1.0) { return; }
185 
186  // do it fast if GammaEnergy < Egsmall
187  // select randomly one element constituing the material
188  const G4Element* anElement = SelectRandomAtom(aMaterial, theGamma, GammaEnergy);
189 
190  if (GammaEnergy < Egsmall) {
191 
192  epsil = epsil0 + (0.5-epsil0)*G4UniformRand();
193 
194  } else {
195  // now comes the case with GammaEnergy >= 2. MeV
196 
197  // Extract Coulomb factor for this Element
198  G4double FZ = 8.*(anElement->GetIonisation()->GetlogZ3());
199  if (GammaEnergy > 50.*MeV) { FZ += 8.*(anElement->GetfCoulomb()); }
200 
201  // limits of the screening variable
202  G4double screenfac = 136.*epsil0/(anElement->GetIonisation()->GetZ3());
203  G4double screenmax = exp ((42.24 - FZ)/8.368) - 0.952 ;
204  G4double screenmin = min(4.*screenfac,screenmax);
205 
206  // limits of the energy sampling
207  G4double epsil1 = 0.5 - 0.5*sqrt(1. - screenmin/screenmax) ;
208  G4double epsilmin = max(epsil0,epsil1) , epsilrange = 0.5 - epsilmin;
209 
210  //
211  // sample the energy rate of the created electron (or positron)
212  //
213  //G4double epsil, screenvar, greject ;
214  G4double screenvar, greject ;
215 
216  G4double F10 = ScreenFunction1(screenmin) - FZ;
217  G4double F20 = ScreenFunction2(screenmin) - FZ;
218  G4double NormF1 = max(F10*epsilrange*epsilrange,0.);
219  G4double NormF2 = max(1.5*F20,0.);
220 
221  do {
222  if ( NormF1/(NormF1+NormF2) > G4UniformRand() ) {
223  epsil = 0.5 - epsilrange*g4pow->A13(G4UniformRand());
224  screenvar = screenfac/(epsil*(1-epsil));
225  greject = (ScreenFunction1(screenvar) - FZ)/F10;
226 
227  } else {
228  epsil = epsilmin + epsilrange*G4UniformRand();
229  screenvar = screenfac/(epsil*(1-epsil));
230  greject = (ScreenFunction2(screenvar) - FZ)/F20;
231  }
232 
233  } while( greject < G4UniformRand() );
234 
235  } // end of epsil sampling
236 
237  //
238  // fixe charges randomly
239  //
240 
241  G4double ElectTotEnergy, PositTotEnergy;
242  if (G4UniformRand() > 0.5) {
243 
244  ElectTotEnergy = (1.-epsil)*GammaEnergy;
245  PositTotEnergy = epsil*GammaEnergy;
246 
247  } else {
248 
249  PositTotEnergy = (1.-epsil)*GammaEnergy;
250  ElectTotEnergy = epsil*GammaEnergy;
251  }
252 
253  //
254  // scattered electron (positron) angles. ( Z - axis along the parent photon)
255  //
256  // universal distribution suggested by L. Urban
257  // (Geant3 manual (1993) Phys211),
258  // derived from Tsai distribution (Rev Mod Phys 49,421(1977))
259 
260  G4double u;
261  static const G4double aa1 = 0.625;
262  static const G4double aa2 = 1.875;
263  static const G4double d = 27. ;
264 
265  if (9./(9.+d) >G4UniformRand()) u= - G4Log(G4UniformRand()*G4UniformRand())/aa1;
266  else u= - G4Log(G4UniformRand()*G4UniformRand())/aa2;
267 
268  G4double TetEl = u*electron_mass_c2/ElectTotEnergy;
269  G4double TetPo = u*electron_mass_c2/PositTotEnergy;
270  G4double Phi = twopi * G4UniformRand();
271  G4double dxEl= sin(TetEl)*cos(Phi),dyEl= sin(TetEl)*sin(Phi),dzEl=cos(TetEl);
272  G4double dxPo=-sin(TetPo)*cos(Phi),dyPo=-sin(TetPo)*sin(Phi),dzPo=cos(TetPo);
273 
274  //
275  // kinematic of the created pair
276  //
277  // the electron and positron are assumed to have a symetric
278  // angular distribution with respect to the Z axis along the parent photon.
279 
280  G4double ElectKineEnergy = max(0.,ElectTotEnergy - electron_mass_c2);
281 
282  G4ThreeVector ElectDirection (dxEl, dyEl, dzEl);
283  ElectDirection.rotateUz(GammaDirection);
284 
285  // create G4DynamicParticle object for the particle1
286  G4DynamicParticle* aParticle1= new G4DynamicParticle(
287  theElectron,ElectDirection,ElectKineEnergy);
288 
289  // the e+ is always created (even with Ekine=0) for further annihilation.
290 
291  G4double PositKineEnergy = max(0.,PositTotEnergy - electron_mass_c2);
292 
293  G4ThreeVector PositDirection (dxPo, dyPo, dzPo);
294  PositDirection.rotateUz(GammaDirection);
295 
296  // create G4DynamicParticle object for the particle2
297  G4DynamicParticle* aParticle2= new G4DynamicParticle(
298  thePositron,PositDirection,PositKineEnergy);
299 
300  // Fill output vector
301  fvect->push_back(aParticle1);
302  fvect->push_back(aParticle2);
303 
304  // kill incident photon
305  fParticleChange->SetProposedKineticEnergy(0.);
306  fParticleChange->ProposeTrackStatus(fStopAndKill);
307 }
G4DynamicParticle::GetKineticEnergy
G4double GetKineticEnergy() const
G4Element::GetfCoulomb
G4double GetfCoulomb() const
Definition: G4Element.hh:190
F20
#define F20
Definition: G4ErrorMatrix.cc:899
G4UniformRand
#define G4UniformRand()
Definition: Randomize.hh:87
G4DynamicParticle::GetMomentumDirection
const G4ThreeVector & GetMomentumDirection() const
python.hepunit.electron_mass_c2
float electron_mass_c2
Definition: hepunit.py:274
F10
#define F10
Definition: G4ErrorMatrix.cc:894
G4IonisParamElm::GetlogZ3
G4double GetlogZ3() const
Definition: G4IonisParamElm.hh:63
G4Log
G4double G4Log(G4double x)
Definition: G4Log.hh:227
G4Pow::A13
G4double A13(G4double A) const
Definition: G4Pow.hh:134
G4INCL::Math::max
T max(const T t1, const T t2)
brief Return the largest of the two arguments
Definition: G4INCLGlobals.hh:116
G4Element::GetIonisation
G4IonisParamElm * GetIonisation() const
Definition: G4Element.hh:198
G4INCL::Math::min
T min(const T t1, const T t2)
brief Return the smallest of the two arguments
Definition: G4INCLGlobals.hh:121
fStopAndKill
Definition: G4TrackStatus.hh:56
G4ParticleChangeForGamma::SetProposedKineticEnergy
void SetProposedKineticEnergy(G4double proposedKinEnergy)
Definition: G4ParticleChangeForGamma.hh:129
G4double
double G4double
Definition: G4Types.hh:76
G4VParticleChange::ProposeTrackStatus
void ProposeTrackStatus(G4TrackStatus status)
G4IonisParamElm::GetZ3
G4double GetZ3() const
Definition: G4IonisParamElm.hh:61
G4VEmModel::SelectRandomAtom
const G4Element * SelectRandomAtom(const G4MaterialCutsCouple *, const G4ParticleDefinition *, G4double kineticEnergy, G4double cutEnergy=0.0, G4double maxEnergy=DBL_MAX)
Definition: G4VEmModel.hh:510
G4MaterialCutsCouple::GetMaterial
const G4Material * GetMaterial() const
Definition: G4MaterialCutsCouple.hh:150
The documentation for this class was generated from the following files:
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