source: trunk/source/processes/electromagnetic/lowenergy/src/G4LivermoreRayleighModel.cc@ 992

Last change on this file since 992 was 991, checked in by garnier, 17 years ago

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25//
26// $Id: G4LivermoreRayleighModel.cc,v 1.1 2008/10/30 14:16:35 sincerti Exp $
27// GEANT4 tag $Name: geant4-09-02 $
28//
29
30#include "G4LivermoreRayleighModel.hh"
31
32//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
33
34using namespace std;
35
36//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
37
38G4LivermoreRayleighModel::G4LivermoreRayleighModel(const G4ParticleDefinition*,
39 const G4String& nam)
40:G4VEmModel(nam),isInitialised(false)
41{
42 lowEnergyLimit = 250 * eV; // SI - Could be 10 eV ?
43 highEnergyLimit = 100 * GeV;
44
45 SetLowEnergyLimit(lowEnergyLimit);
46 SetHighEnergyLimit(highEnergyLimit);
47 //
48 verboseLevel= 0;
49 // Verbosity scale:
50 // 0 = nothing
51 // 1 = warning for energy non-conservation
52 // 2 = details of energy budget
53 // 3 = calculation of cross sections, file openings, sampling of atoms
54 // 4 = entering in methods
55
56 G4cout << "Livermore Rayleigh is constructed " << G4endl
57 << "Energy range: "
58 << lowEnergyLimit / keV << " keV - "
59 << highEnergyLimit / GeV << " GeV"
60 << G4endl;
61}
62
63//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
64
65G4LivermoreRayleighModel::~G4LivermoreRayleighModel()
66{
67 delete meanFreePathTable;
68 delete crossSectionHandler;
69 delete formFactorData;
70}
71
72//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
73
74void G4LivermoreRayleighModel::Initialise(const G4ParticleDefinition* particle,
75 const G4DataVector& cuts)
76{
77 if (verboseLevel > 3)
78 G4cout << "Calling G4LivermoreRayleighModel::Initialise()" << G4endl;
79
80 InitialiseElementSelectors(particle,cuts);
81
82 // Energy limits
83
84 if (LowEnergyLimit() < lowEnergyLimit)
85 {
86 G4cout << "G4LivermoreRayleighModel: low energy limit increased from " <<
87 LowEnergyLimit()/eV << " eV to " << lowEnergyLimit << " eV" << G4endl;
88 SetLowEnergyLimit(lowEnergyLimit);
89 }
90
91 if (HighEnergyLimit() > highEnergyLimit)
92 {
93 G4cout << "G4LivermoreRayleighModel: high energy limit decreased from " <<
94 HighEnergyLimit()/GeV << " GeV to " << highEnergyLimit << " GeV" << G4endl;
95 SetHighEnergyLimit(highEnergyLimit);
96 }
97
98 // Data are read for all materials
99
100 crossSectionHandler = new G4CrossSectionHandler;
101 crossSectionHandler->Clear();
102 G4String crossSectionFile = "rayl/re-cs-";
103 crossSectionHandler->LoadData(crossSectionFile);
104
105 meanFreePathTable = 0;
106 meanFreePathTable = crossSectionHandler->BuildMeanFreePathForMaterials();
107
108 G4VDataSetAlgorithm* ffInterpolation = new G4LogLogInterpolation;
109 G4String formFactorFile = "rayl/re-ff-";
110 formFactorData = new G4CompositeEMDataSet(ffInterpolation,1.,1.);
111 formFactorData->LoadData(formFactorFile);
112
113 //
114
115 if (verboseLevel > 2)
116 G4cout << "Loaded cross section files for Livermore Rayleigh model" << G4endl;
117
118 G4cout << "Livermore Rayleigh model is initialized " << G4endl
119 << "Energy range: "
120 << LowEnergyLimit() / keV << " keV - "
121 << HighEnergyLimit() / GeV << " GeV"
122 << G4endl;
123
124 if(isInitialised) return;
125
126 if(pParticleChange)
127 fParticleChange = reinterpret_cast<G4ParticleChangeForGamma*>(pParticleChange);
128 else
129 fParticleChange = new G4ParticleChangeForGamma();
130
131 isInitialised = true;
132
133}
134
135//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
136
137G4double G4LivermoreRayleighModel::ComputeCrossSectionPerAtom(
138 const G4ParticleDefinition*,
139 G4double GammaEnergy,
140 G4double Z, G4double,
141 G4double, G4double)
142{
143 if (verboseLevel > 3)
144 G4cout << "Calling CrossSectionPerAtom() of G4LivermoreRayleighModel" << G4endl;
145
146 G4double cs = crossSectionHandler->FindValue(G4int(Z), GammaEnergy);
147 return cs;
148}
149
150//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
151
152void G4LivermoreRayleighModel::SampleSecondaries(std::vector<G4DynamicParticle*>* /*fvect*/,
153 const G4MaterialCutsCouple* couple,
154 const G4DynamicParticle* aDynamicGamma,
155 G4double,
156 G4double)
157{
158 if (verboseLevel > 3)
159 G4cout << "Calling SampleSecondaries() of G4LivermoreRayleighModel" << G4endl;
160
161 G4double photonEnergy0 = aDynamicGamma->GetKineticEnergy();
162
163 if (photonEnergy0 <= lowEnergyLimit)
164 {
165 fParticleChange->ProposeTrackStatus(fStopAndKill);
166 fParticleChange->SetProposedKineticEnergy(0.);
167 fParticleChange->ProposeLocalEnergyDeposit(photonEnergy0);
168 // SI - IS THE FOLLOWING RETURN NECESSARY ?
169 return ;
170 }
171
172 G4ParticleMomentum photonDirection0 = aDynamicGamma->GetMomentumDirection();
173
174 // Select randomly one element in the current material
175 G4int Z = crossSectionHandler->SelectRandomAtom(couple,photonEnergy0);
176
177 // Sample the angle of the scattered photon
178
179 G4double wlPhoton = h_Planck*c_light/photonEnergy0;
180
181 G4double gReject,x,dataFormFactor;
182 G4double randomFormFactor;
183 G4double cosTheta;
184 G4double sinTheta;
185 G4double fcostheta;
186
187 do
188 {
189 do
190 {
191 cosTheta = 2. * G4UniformRand() - 1.;
192 fcostheta = ( 1. + cosTheta*cosTheta)/2.;
193 } while (fcostheta < G4UniformRand());
194
195 G4double sinThetaHalf = std::sqrt((1. - cosTheta) / 2.);
196 x = sinThetaHalf / (wlPhoton/cm);
197 if (x > 1.e+005)
198 dataFormFactor = formFactorData->FindValue(x,Z-1);
199 else
200 dataFormFactor = formFactorData->FindValue(0.,Z-1);
201 randomFormFactor = G4UniformRand() * Z * Z;
202 sinTheta = std::sqrt(1. - cosTheta*cosTheta);
203 gReject = dataFormFactor * dataFormFactor;
204
205 } while( gReject < randomFormFactor);
206
207 // Scattered photon angles. ( Z - axis along the parent photon)
208 G4double phi = twopi * G4UniformRand() ;
209 G4double dirX = sinTheta*std::cos(phi);
210 G4double dirY = sinTheta*std::sin(phi);
211 G4double dirZ = cosTheta;
212
213 // Update G4VParticleChange for the scattered photon
214 G4ThreeVector photonDirection1(dirX, dirY, dirZ);
215 photonDirection1.rotateUz(photonDirection0);
216 fParticleChange->ProposeMomentumDirection(photonDirection1);
217
218 fParticleChange->SetProposedKineticEnergy(photonEnergy0);
219}
220
221//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
222
223G4double G4LivermoreRayleighModel::GetMeanFreePath(const G4Track& track,
224 G4double, // previousStepSize
225 G4ForceCondition*)
226{
227 const G4DynamicParticle* photon = track.GetDynamicParticle();
228 G4double energy = photon->GetKineticEnergy();
229 const G4MaterialCutsCouple* couple = track.GetMaterialCutsCouple();
230 size_t materialIndex = couple->GetIndex();
231
232 G4double meanFreePath;
233 if (energy > highEnergyLimit) meanFreePath = meanFreePathTable->FindValue(highEnergyLimit,materialIndex);
234 else if (energy < lowEnergyLimit) meanFreePath = DBL_MAX;
235 else meanFreePath = meanFreePathTable->FindValue(energy,materialIndex);
236 return meanFreePath;
237}
238
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