source: trunk/source/processes/electromagnetic/standard/include/G4eBremsstrahlungRelModel.hh@ 1036

Last change on this file since 1036 was 1007, checked in by garnier, 17 years ago

update to geant4.9.2
File size: 7.7 KB
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1//
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4// * *
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14// * regarding this software system or assume any liability for its *
15// * use. Please see the license in the file LICENSE and URL above *
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18// * This code implementation is the result of the scientific and *
19// * technical work of the GEANT4 collaboration. *
20// * By using, copying, modifying or distributing the software (or *
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24// ********************************************************************
25//
26// $Id: G4eBremsstrahlungRelModel.hh,v 1.10 2008/11/14 09:25:19 vnivanch Exp $
27// GEANT4 tag $Name: geant4-09-02 $
28//
29// -------------------------------------------------------------------
30//
31// GEANT4 Class header file
32//
33//
34// File name: G4eBremsstrahlungRelModel
35// extention of standard G4eBremsstrahlungModel
36//
37// Author: Andreas Schaelicke
38//
39// Creation date: 28.03.2008
40//
41// Modifications:
42//
43//
44// Class Description:
45//
46// Implementation of energy loss for gamma emission by electrons and
47// positrons including an improved version of the LPM effect
48
49// -------------------------------------------------------------------
50//
51
52#ifndef G4eBremsstrahlungRelModel_h
53#define G4eBremsstrahlungRelModel_h 1
54
55#include "G4VEmModel.hh"
56#include "G4NistManager.hh"
57
58class G4ParticleChangeForLoss;
59class G4PhysicsVector;
60
61class G4eBremsstrahlungRelModel : public G4VEmModel
62{
63
64public:
65
66 G4eBremsstrahlungRelModel(const G4ParticleDefinition* p = 0,
67 const G4String& nam = "eBremRel");
68
69 virtual ~G4eBremsstrahlungRelModel();
70
71 virtual void Initialise(const G4ParticleDefinition*, const G4DataVector&);
72
73 G4double MinEnergyCut(const G4ParticleDefinition*,
74 const G4MaterialCutsCouple*);
75
76 virtual G4double ComputeDEDXPerVolume(const G4Material*,
77 const G4ParticleDefinition*,
78 G4double kineticEnergy,
79 G4double cutEnergy);
80
81 virtual G4double ComputeCrossSectionPerAtom(const G4ParticleDefinition*,
82 G4double tkin,
83 G4double Z, G4double,
84 G4double cutEnergy,
85 G4double maxEnergy = DBL_MAX);
86
87 virtual void SampleSecondaries(std::vector<G4DynamicParticle*>*,
88 const G4MaterialCutsCouple*,
89 const G4DynamicParticle*,
90 G4double cutEnergy,
91 G4double maxEnergy);
92
93 virtual void SetupForMaterial(const G4ParticleDefinition*,
94 const G4Material*,G4double);
95
96 inline void SetLPMconstant(G4double val);
97 inline G4double LPMconstant() const;
98
99protected:
100
101 inline G4double MaxSecondaryEnergy(const G4ParticleDefinition*,
102 G4double kineticEnergy);
103
104private:
105
106 void InitialiseConstants();
107
108 void CalcLPMFunctions(G4double gammaEnergy);
109
110 G4double ComputeBremLoss(G4double cutEnergy);
111
112 G4double ComputeXSectionPerAtom(G4double cutEnergy);
113
114 G4double ComputeDXSectionPerAtom(G4double gammaEnergy);
115
116 G4double ComputeRelDXSectionPerAtom(G4double gammaEnergy);
117
118 void SetParticle(const G4ParticleDefinition* p);
119
120 // * fast inline functions *
121 inline void SetCurrentElement(const G4double);
122
123 inline G4double Phi1(G4double,G4double);
124 inline G4double Phi1M2(G4double,G4double);
125 inline G4double Psi1(G4double,G4double);
126 inline G4double Psi1M2(G4double,G4double);
127
128 // hide assignment operator
129 G4eBremsstrahlungRelModel & operator=(const G4eBremsstrahlungRelModel &right);
130 G4eBremsstrahlungRelModel(const G4eBremsstrahlungRelModel&);
131
132protected:
133
134 G4NistManager* nist;
135 const G4ParticleDefinition* particle;
136 G4ParticleDefinition* theGamma;
137 G4ParticleChangeForLoss* fParticleChange;
138
139 static const G4double xgi[8], wgi[8];
140 static const G4double Fel_light[5];
141 static const G4double Finel_light[5];
142
143 G4double minThreshold;
144
145 // cash
146 G4double particleMass;
147 G4double kinEnergy;
148 G4double totalEnergy;
149 G4double currentZ;
150 G4double z13, z23, lnZ;
151 G4double Fel, Finel, fCoulomb, fMax;
152 G4double densityFactor;
153 G4double densityCorr;
154
155 // LPM effect
156 G4double lpmEnergy;
157 G4PhysicsVector *fXiLPM, *fPhiLPM, *fGLPM;
158 G4double xiLPM, phiLPM, gLPM;
159
160 // critical gamma energies
161 G4double klpm, kp;
162
163 G4bool isElectron;
164
165private:
166 // consts
167 G4double highKinEnergy;
168 G4double lowKinEnergy;
169 G4double fMigdalConstant;
170 G4double fLPMconstant;
171 G4double bremFactor;
172 G4double energyThresholdLPM;
173 G4double facFel, facFinel;
174 G4double preS1,logTwo;
175
176 G4bool use_completescreening;
177
178 G4bool isInitialised;
179};
180
181//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
182
183inline void G4eBremsstrahlungRelModel::SetCurrentElement(const G4double Z)
184{
185 if(Z != currentZ) {
186 currentZ = Z;
187
188 G4int iz = G4int(Z);
189 z13 = nist->GetZ13(iz);
190 z23 = z13*z13;
191 lnZ = nist->GetLOGZ(iz);
192
193 if (iz <= 4) {
194 Fel = Fel_light[iz];
195 Finel = Finel_light[iz] ;
196 }
197 else {
198 Fel = facFel - lnZ/3. ;
199 Finel = facFinel - 2.*lnZ/3. ;
200 }
201
202 fCoulomb=GetCurrentElement()->GetfCoulomb();
203 fMax = Fel-fCoulomb + Finel/currentZ + (1.+1./currentZ)/12.;
204 }
205}
206
207//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
208
209inline G4double
210G4eBremsstrahlungRelModel::MaxSecondaryEnergy(const G4ParticleDefinition*,
211 G4double kineticEnergy)
212{
213 return kineticEnergy;
214}
215
216//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
217
218
219inline G4double G4eBremsstrahlungRelModel::Phi1(G4double gg, G4double)
220{
221 // Thomas-Fermi FF from Tsai, eq.(3.38) for Z>=5
222 return 20.863 - 2.*std::log(1. + sqr(0.55846*gg) )
223 - 4.*( 1. - 0.6*std::exp(-0.9*gg) - 0.4*std::exp(-1.5*gg) );
224}
225
226inline G4double G4eBremsstrahlungRelModel::Phi1M2(G4double gg, G4double)
227{
228 // Thomas-Fermi FF from Tsai, eq. (3.39) for Z>=5
229 // return Phi1(gg,Z) -
230 return 2./(3.*(1. + 6.5*gg +6.*gg*gg) );
231}
232
233inline G4double G4eBremsstrahlungRelModel::Psi1(G4double eps, G4double)
234{
235 // Thomas-Fermi FF from Tsai, eq.(3.40) for Z>=5
236 return 28.340 - 2.*std::log(1. + sqr(3.621*eps) )
237 - 4.*( 1. - 0.7*std::exp(-8*eps) - 0.3*std::exp(-29.*eps) );
238}
239
240inline G4double G4eBremsstrahlungRelModel::Psi1M2(G4double eps, G4double)
241{
242 // Thomas-Fermi FF from Tsai, eq. (3.41) for Z>=5
243 return 2./(3.*(1. + 40.*eps +400.*eps*eps) );
244}
245
246//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
247
248inline
249void G4eBremsstrahlungRelModel::SetLPMconstant(G4double val)
250{
251 fLPMconstant = val;
252}
253
254//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
255
256inline
257G4double G4eBremsstrahlungRelModel::LPMconstant() const
258{
259 return fLPMconstant;
260}
261
262//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
263
264
265#endif
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