source: trunk/source/processes/electromagnetic/standard/src/G4PEEffectFluoModel.cc

Last change on this file was 1350, checked in by garnier, 15 years ago

update to last version 4.9.4
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25//
26// $Id: G4PEEffectFluoModel.cc,v 1.1 2010/09/03 14:11:16 vnivanch Exp $
27// GEANT4 tag $Name: emstand-V09-03-24 $
28//
29// -------------------------------------------------------------------
30//
31// GEANT4 Class file
32//
33//
34// File name: G4PEEffectFluoModel
35//
36// Author: Vladimir Ivanchenko on base of G4PEEffectModel
37//
38// Creation date: 13.06.2010
39//
40// Modifications:
41//
42// Class Description:
43// Implementation of the photo-electric effect with deexcitation
44//
45// -------------------------------------------------------------------
46//
47//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
48//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
49
50#include "G4PEEffectFluoModel.hh"
51#include "G4Electron.hh"
52#include "G4Gamma.hh"
53#include "Randomize.hh"
54#include "G4DataVector.hh"
55#include "G4ParticleChangeForGamma.hh"
56#include "G4VAtomDeexcitation.hh"
57#include "G4LossTableManager.hh"
58
59//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
60
61using namespace std;
62
63G4PEEffectFluoModel::G4PEEffectFluoModel(const G4String& nam)
64 : G4VEmModel(nam),isInitialized(false)
65{
66 theGamma = G4Gamma::Gamma();
67 theElectron = G4Electron::Electron();
68 fminimalEnergy = 1.0*eV;
69}
70
71//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
72
73G4PEEffectFluoModel::~G4PEEffectFluoModel()
74{}
75
76//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
77
78void G4PEEffectFluoModel::Initialise(const G4ParticleDefinition*,
79 const G4DataVector&)
80{
81 fAtomDeexcitation = G4LossTableManager::Instance()->AtomDeexcitation();
82
83 if (isInitialized) return;
84 fParticleChange = GetParticleChangeForGamma();
85 isInitialized = true;
86}
87
88//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.....
89
90G4double
91G4PEEffectFluoModel::ComputeCrossSectionPerAtom(const G4ParticleDefinition*,
92 G4double energy,
93 G4double Z, G4double,
94 G4double, G4double)
95{
96 G4double* SandiaCof = G4SandiaTable::GetSandiaCofPerAtom((G4int)Z, energy);
97
98 G4double energy2 = energy*energy;
99 G4double energy3 = energy*energy2;
100 G4double energy4 = energy2*energy2;
101
102 return SandiaCof[0]/energy + SandiaCof[1]/energy2 +
103 SandiaCof[2]/energy3 + SandiaCof[3]/energy4;
104}
105
106//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
107
108G4double
109G4PEEffectFluoModel::CrossSectionPerVolume(const G4Material* material,
110 const G4ParticleDefinition*,
111 G4double energy,
112 G4double, G4double)
113{
114 G4double* SandiaCof =
115 material->GetSandiaTable()->GetSandiaCofForMaterial(energy);
116
117 G4double energy2 = energy*energy;
118 G4double energy3 = energy*energy2;
119 G4double energy4 = energy2*energy2;
120
121 return SandiaCof[0]/energy + SandiaCof[1]/energy2 +
122 SandiaCof[2]/energy3 + SandiaCof[3]/energy4;
123}
124
125//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
126
127void
128G4PEEffectFluoModel::SampleSecondaries(std::vector<G4DynamicParticle*>* fvect,
129 const G4MaterialCutsCouple* couple,
130 const G4DynamicParticle* aDynamicPhoton,
131 G4double,
132 G4double)
133{
134 const G4Material* aMaterial = couple->GetMaterial();
135
136 G4double energy = aDynamicPhoton->GetKineticEnergy();
137 G4ParticleMomentum PhotonDirection = aDynamicPhoton->GetMomentumDirection();
138
139 // select randomly one element constituing the material.
140 const G4Element* anElement = SelectRandomAtom(aMaterial,theGamma,energy);
141
142 //
143 // Photo electron
144 //
145
146 // Select atomic shell
147 G4int nShells = anElement->GetNbOfAtomicShells();
148 G4int i = 0;
149 while ((i<nShells) && (energy<anElement->GetAtomicShell(i))) { ++i; }
150
151 // no shell available
152 if (i == nShells) { return; }
153
154 G4double bindingEnergy = anElement->GetAtomicShell(i);
155 G4double ElecKineEnergy = energy - bindingEnergy;
156
157 // create photo electron
158 //
159 if (ElecKineEnergy > fminimalEnergy) {
160 G4double cosTeta = ElecCosThetaDistribution(ElecKineEnergy);
161 G4double sinTeta = sqrt(1.-cosTeta*cosTeta);
162 G4double Phi = twopi * G4UniformRand();
163 G4double dirx = sinTeta*cos(Phi),diry = sinTeta*sin(Phi),dirz = cosTeta;
164 G4ThreeVector ElecDirection(dirx,diry,dirz);
165 ElecDirection.rotateUz(PhotonDirection);
166 //
167 G4DynamicParticle* aParticle = new G4DynamicParticle (
168 theElectron,ElecDirection, ElecKineEnergy);
169 fvect->push_back(aParticle);
170 }
171
172 // sample deexcitation
173 //
174 if(fAtomDeexcitation) {
175 G4int Z = (G4int)anElement->GetZ();
176 G4AtomicShellEnumerator as = G4AtomicShellEnumerator(i);
177 const G4AtomicShell* shell = fAtomDeexcitation->GetAtomicShell(Z, as);
178 fAtomDeexcitation->GenerateParticles(fvect, shell, Z, couple->GetIndex());
179 }
180
181 // kill primary photon
182 fParticleChange->SetProposedKineticEnergy(0.);
183 fParticleChange->ProposeTrackStatus(fStopAndKill);
184 fParticleChange->ProposeLocalEnergyDeposit(bindingEnergy);
185}
186
187//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
188
189G4double G4PEEffectFluoModel::ElecCosThetaDistribution(G4double kineEnergy)
190{
191 // Compute Theta distribution of the emitted electron, with respect to the
192 // incident Gamma.
193 // The Sauter-Gavrila distribution for the K-shell is used.
194 //
195 G4double costeta = 1.;
196 G4double gamma = 1. + kineEnergy/electron_mass_c2;
197 if (gamma > 5.) return costeta;
198 G4double beta = sqrt(gamma*gamma-1.)/gamma;
199 G4double b = 0.5*gamma*(gamma-1.)*(gamma-2);
200
201 G4double rndm,term,greject,grejsup;
202 if (gamma < 2.) grejsup = gamma*gamma*(1.+b-beta*b);
203 else grejsup = gamma*gamma*(1.+b+beta*b);
204
205 do { rndm = 1.-2*G4UniformRand();
206 costeta = (rndm+beta)/(rndm*beta+1.);
207 term = 1.-beta*costeta;
208 greject = (1.-costeta*costeta)*(1.+b*term)/(term*term);
209 } while(greject < G4UniformRand()*grejsup);
210
211 return costeta;
212}
213
214//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
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