Geant4  10.03.p01
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G4KleinNishinaCompton Class Reference

#include <G4KleinNishinaCompton.hh>

Inheritance diagram for G4KleinNishinaCompton:
Collaboration diagram for G4KleinNishinaCompton:

Public Member Functions

 G4KleinNishinaCompton (const G4ParticleDefinition *p=nullptr, const G4String &nam="Klein-Nishina")
 
virtual ~G4KleinNishinaCompton ()
 
virtual void Initialise (const G4ParticleDefinition *, const G4DataVector &) override
 
virtual void InitialiseLocal (const G4ParticleDefinition *, G4VEmModel *masterModel) override
 
virtual G4double ComputeCrossSectionPerAtom (const G4ParticleDefinition *, G4double kinEnergy, G4double Z, G4double A, G4double cut, G4double emax) override
 
virtual void SampleSecondaries (std::vector< G4DynamicParticle * > *, const G4MaterialCutsCouple *, const G4DynamicParticle *, G4double tmin, G4double maxEnergy) override
 
- 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 GetPartialCrossSection (const G4Material *, G4int level, const G4ParticleDefinition *, G4double kineticEnergy)
 
virtual G4double ComputeCrossSectionPerShell (const G4ParticleDefinition *, G4int Z, G4int shellIdx, G4double kinEnergy, 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 *)
 
virtual void ModelDescription (std::ostream &outFile) const
 
void InitialiseElementSelectors (const G4ParticleDefinition *, const G4DataVector &)
 
std::vector
< G4EmElementSelector * > * 
GetElementSelectors ()
 
void SetElementSelectors (std::vector< G4EmElementSelector * > *)
 
virtual 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 G4ElementSelectRandomAtom (const G4MaterialCutsCouple *, const G4ParticleDefinition *, G4double kineticEnergy, G4double cutEnergy=0.0, G4double maxEnergy=DBL_MAX)
 
const G4ElementSelectRandomAtom (const G4Material *, const G4ParticleDefinition *, G4double kineticEnergy, G4double cutEnergy=0.0, G4double maxEnergy=DBL_MAX)
 
G4int SelectRandomAtomNumber (const G4Material *)
 
void SetParticleChange (G4VParticleChange *, G4VEmFluctuationModel *f=nullptr)
 
void SetCrossSectionTable (G4PhysicsTable *, G4bool isLocal)
 
G4ElementDataGetElementData ()
 
G4PhysicsTableGetCrossSectionTable ()
 
G4VEmFluctuationModelGetModelOfFluctuations ()
 
G4VEmAngularDistributionGetAngularDistribution ()
 
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 G4StringGetName () const
 
void SetCurrentCouple (const G4MaterialCutsCouple *)
 
const G4ElementGetCurrentElement () const
 
const G4IsotopeGetCurrentIsotope () const
 
G4bool IsLocked () const
 
void SetLocked (G4bool)
 

Protected Attributes

G4ParticleDefinitiontheGamma
 
G4ParticleDefinitiontheElectron
 
G4ParticleChangeForGammafParticleChange
 
G4double lowestSecondaryEnergy
 
- Protected Attributes inherited from G4VEmModel
G4ElementDatafElementData
 
G4VParticleChangepParticleChange
 
G4PhysicsTablexSectionTable
 
const std::vector< G4double > * theDensityFactor
 
const std::vector< G4int > * theDensityIdx
 
size_t idxTable
 

Additional Inherited Members

- Protected Member Functions inherited from G4VEmModel
G4ParticleChangeForLossGetParticleChangeForLoss ()
 
G4ParticleChangeForGammaGetParticleChangeForGamma ()
 
virtual G4double MaxSecondaryEnergy (const G4ParticleDefinition *, G4double kineticEnergy)
 
const G4MaterialCutsCoupleCurrentCouple () const
 
void SetCurrentElement (const G4Element *)
 
- Static Protected Attributes inherited from G4VEmModel
static const G4double inveplus = 1.0/CLHEP::eplus
 

Detailed Description

Definition at line 58 of file G4KleinNishinaCompton.hh.

Constructor & Destructor Documentation

G4KleinNishinaCompton::G4KleinNishinaCompton ( const G4ParticleDefinition p = nullptr,
const G4String nam = "Klein-Nishina" 
)
explicit

Definition at line 65 of file G4KleinNishinaCompton.cc.

67  : G4VEmModel(nam)
68 {
71  lowestSecondaryEnergy = 100.0*eV;
72  fParticleChange = nullptr;
73 }
G4ParticleChangeForGamma * fParticleChange
G4VEmModel(const G4String &nam)
Definition: G4VEmModel.cc:68
static constexpr double eV
Definition: G4SIunits.hh:215
static G4Gamma * Gamma()
Definition: G4Gamma.cc:86
static G4Electron * Electron()
Definition: G4Electron.cc:94
G4ParticleDefinition * theElectron
G4ParticleDefinition * theGamma

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G4KleinNishinaCompton::~G4KleinNishinaCompton ( )
virtual

Definition at line 77 of file G4KleinNishinaCompton.cc.

78 {}

Member Function Documentation

G4double G4KleinNishinaCompton::ComputeCrossSectionPerAtom ( const G4ParticleDefinition ,
G4double  kinEnergy,
G4double  Z,
G4double  A,
G4double  cut,
G4double  emax 
)
overridevirtual

Reimplemented from G4VEmModel.

Reimplemented in G4PolarizedComptonModel.

Definition at line 101 of file G4KleinNishinaCompton.cc.

106 {
107  G4double xSection = 0.0 ;
108  if (GammaEnergy <= LowEnergyLimit()) { return xSection; }
109 
110  static const G4double a = 20.0 , b = 230.0 , c = 440.0;
111 
112  static const G4double
113  d1= 2.7965e-1*CLHEP::barn, d2=-1.8300e-1*CLHEP::barn,
114  d3= 6.7527 *CLHEP::barn, d4=-1.9798e+1*CLHEP::barn,
115  e1= 1.9756e-5*CLHEP::barn, e2=-1.0205e-2*CLHEP::barn,
116  e3=-7.3913e-2*CLHEP::barn, e4= 2.7079e-2*CLHEP::barn,
117  f1=-3.9178e-7*CLHEP::barn, f2= 6.8241e-5*CLHEP::barn,
118  f3= 6.0480e-5*CLHEP::barn, f4= 3.0274e-4*CLHEP::barn;
119 
120  G4double p1Z = Z*(d1 + e1*Z + f1*Z*Z), p2Z = Z*(d2 + e2*Z + f2*Z*Z),
121  p3Z = Z*(d3 + e3*Z + f3*Z*Z), p4Z = Z*(d4 + e4*Z + f4*Z*Z);
122 
123  G4double T0 = 15.0*keV;
124  if (Z < 1.5) { T0 = 40.0*keV; }
125 
126  G4double X = max(GammaEnergy, T0) / electron_mass_c2;
127  xSection = p1Z*G4Log(1.+2.*X)/X
128  + (p2Z + p3Z*X + p4Z*X*X)/(1. + a*X + b*X*X + c*X*X*X);
129 
130  // modification for low energy. (special case for Hydrogen)
131  if (GammaEnergy < T0) {
132  static const G4double dT0 = keV;
133  X = (T0+dT0) / electron_mass_c2 ;
134  G4double sigma = p1Z*G4Log(1.+2*X)/X
135  + (p2Z + p3Z*X + p4Z*X*X)/(1. + a*X + b*X*X + c*X*X*X);
136  G4double c1 = -T0*(sigma-xSection)/(xSection*dT0);
137  G4double c2 = 0.150;
138  if (Z > 1.5) { c2 = 0.375-0.0556*G4Log(Z); }
139  G4double y = G4Log(GammaEnergy/T0);
140  xSection *= G4Exp(-y*(c1+c2*y));
141  }
142  // G4cout<<"e= "<< GammaEnergy<<" Z= "<<Z<<" cross= " << xSection << G4endl;
143  return xSection;
144 }
G4double LowEnergyLimit() const
Definition: G4VEmModel.hh:640
static const G4double d2
static constexpr double electron_mass_c2
static constexpr double barn
Definition: SystemOfUnits.h:85
static const G4double d1
G4double G4Log(G4double x)
Definition: G4Log.hh:230
G4double G4Exp(G4double initial_x)
Exponential Function double precision.
Definition: G4Exp.hh:183
T max(const T t1, const T t2)
brief Return the largest of the two arguments
static const G4double T0[78]
double G4double
Definition: G4Types.hh:76
static constexpr double keV
Definition: G4SIunits.hh:216

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void G4KleinNishinaCompton::Initialise ( const G4ParticleDefinition p,
const G4DataVector cuts 
)
overridevirtual

Implements G4VEmModel.

Definition at line 82 of file G4KleinNishinaCompton.cc.

84 {
85  if(IsMaster()) { InitialiseElementSelectors(p, cuts); }
86  if(nullptr == fParticleChange) {
88  }
89 }
G4ParticleChangeForGamma * fParticleChange
void InitialiseElementSelectors(const G4ParticleDefinition *, const G4DataVector &)
Definition: G4VEmModel.cc:146
G4bool IsMaster() const
Definition: G4VEmModel.hh:717
G4ParticleChangeForGamma * GetParticleChangeForGamma()
Definition: G4VEmModel.cc:132

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void G4KleinNishinaCompton::InitialiseLocal ( const G4ParticleDefinition ,
G4VEmModel masterModel 
)
overridevirtual

Reimplemented from G4VEmModel.

Definition at line 93 of file G4KleinNishinaCompton.cc.

95 {
97 }
std::vector< G4EmElementSelector * > * GetElementSelectors()
Definition: G4VEmModel.hh:801
void SetElementSelectors(std::vector< G4EmElementSelector * > *)
Definition: G4VEmModel.hh:809

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void G4KleinNishinaCompton::SampleSecondaries ( std::vector< G4DynamicParticle * > *  fvect,
const G4MaterialCutsCouple ,
const G4DynamicParticle aDynamicGamma,
G4double  tmin,
G4double  maxEnergy 
)
overridevirtual

Implements G4VEmModel.

Reimplemented in G4PolarizedComptonModel, and G4HeatedKleinNishinaCompton.

Definition at line 148 of file G4KleinNishinaCompton.cc.

154 {
155  // The scattered gamma energy is sampled according to Klein - Nishina formula.
156  // The random number techniques of Butcher & Messel are used
157  // (Nuc Phys 20(1960),15).
158  // Note : Effects due to binding of atomic electrons are negliged.
159 
160  G4double gamEnergy0 = aDynamicGamma->GetKineticEnergy();
161 
162  // do nothing below the threshold
163  if(gamEnergy0 <= LowEnergyLimit()) { return; }
164 
165  G4double E0_m = gamEnergy0 / electron_mass_c2 ;
166 
167  G4ThreeVector gamDirection0 = aDynamicGamma->GetMomentumDirection();
168 
169  //
170  // sample the energy rate of the scattered gamma
171  //
172 
173  G4double epsilon, epsilonsq, onecost, sint2, greject ;
174 
175  G4double eps0 = 1./(1. + 2.*E0_m);
176  G4double epsilon0sq = eps0*eps0;
177  G4double alpha1 = - G4Log(eps0);
178  G4double alpha2 = alpha1 + 0.5*(1.- epsilon0sq);
179 
180  CLHEP::HepRandomEngine* rndmEngineMod = G4Random::getTheEngine();
181  G4double rndm[3];
182 
183  static const G4int nlooplim = 1000;
184  G4int nloop = 0;
185  do {
186  ++nloop;
187  // false interaction if too many iterations
188  if(nloop > nlooplim) { return; }
189 
190  // 3 random numbers to sample scattering
191  rndmEngineMod->flatArray(3, rndm);
192 
193  if ( alpha1 > alpha2*rndm[0] ) {
194  epsilon = G4Exp(-alpha1*rndm[1]); // eps0**r
195  epsilonsq = epsilon*epsilon;
196 
197  } else {
198  epsilonsq = epsilon0sq + (1.- epsilon0sq)*rndm[1];
199  epsilon = sqrt(epsilonsq);
200  };
201 
202  onecost = (1.- epsilon)/(epsilon*E0_m);
203  sint2 = onecost*(2.-onecost);
204  greject = 1. - epsilon*sint2/(1.+ epsilonsq);
205 
206  // Loop checking, 03-Aug-2015, Vladimir Ivanchenko
207  } while (greject < rndm[2]);
208 
209  //
210  // scattered gamma angles. ( Z - axis along the parent gamma)
211  //
212 
213  if(sint2 < 0.0) { sint2 = 0.0; }
214  G4double cosTeta = 1. - onecost;
215  G4double sinTeta = sqrt (sint2);
216  G4double Phi = twopi * rndmEngineMod->flat();
217 
218  //
219  // update G4VParticleChange for the scattered gamma
220  //
221 
222  G4ThreeVector gamDirection1(sinTeta*cos(Phi), sinTeta*sin(Phi), cosTeta);
223  gamDirection1.rotateUz(gamDirection0);
224  G4double gamEnergy1 = epsilon*gamEnergy0;
225  G4double edep = 0.0;
226  if(gamEnergy1 > lowestSecondaryEnergy) {
229  } else {
232  edep = gamEnergy1;
233  }
234 
235  //
236  // kinematic of the scattered electron
237  //
238 
239  G4double eKinEnergy = gamEnergy0 - gamEnergy1;
240 
241  if(eKinEnergy > lowestSecondaryEnergy) {
242  G4ThreeVector eDirection = gamEnergy0*gamDirection0 - gamEnergy1*gamDirection1;
243  eDirection = eDirection.unit();
244 
245  // create G4DynamicParticle object for the electron.
246  G4DynamicParticle* dp = new G4DynamicParticle(theElectron,eDirection,eKinEnergy);
247  fvect->push_back(dp);
248  } else {
249  edep += eKinEnergy;
250  }
251  // energy balance
252  if(edep > 0.0) {
254  }
255 }
G4double LowEnergyLimit() const
Definition: G4VEmModel.hh:640
G4ParticleChangeForGamma * fParticleChange
G4double GetKineticEnergy() const
static const G4int nlooplim
virtual double flat()=0
int G4int
Definition: G4Types.hh:78
void ProposeMomentumDirection(G4double Px, G4double Py, G4double Pz)
void ProposeLocalEnergyDeposit(G4double anEnergyPart)
static constexpr double twopi
Definition: G4SIunits.hh:76
static constexpr double electron_mass_c2
const G4ThreeVector & GetMomentumDirection() const
G4double G4Log(G4double x)
Definition: G4Log.hh:230
G4double G4Exp(G4double initial_x)
Exponential Function double precision.
Definition: G4Exp.hh:183
Hep3Vector unit() const
void SetProposedKineticEnergy(G4double proposedKinEnergy)
G4ParticleDefinition * theElectron
double G4double
Definition: G4Types.hh:76
void ProposeTrackStatus(G4TrackStatus status)
virtual void flatArray(const int size, double *vect)=0
double epsilon(double density, double temperature)

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Member Data Documentation

G4ParticleChangeForGamma* G4KleinNishinaCompton::fParticleChange
protected

Definition at line 92 of file G4KleinNishinaCompton.hh.

G4double G4KleinNishinaCompton::lowestSecondaryEnergy
protected

Definition at line 93 of file G4KleinNishinaCompton.hh.

G4ParticleDefinition* G4KleinNishinaCompton::theElectron
protected

Definition at line 91 of file G4KleinNishinaCompton.hh.

G4ParticleDefinition* G4KleinNishinaCompton::theGamma
protected

Definition at line 90 of file G4KleinNishinaCompton.hh.


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