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G4eBremsstrahlungRelModel.hh
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26 // $Id: G4eBremsstrahlungRelModel.hh 98737 2016-08-09 12:51:38Z gcosmo $
27 //
28 // -------------------------------------------------------------------
29 //
30 // GEANT4 Class header file
31 //
32 //
33 // File name: G4eBremsstrahlungRelModel
34 // extention of standard G4eBremsstrahlungModel
35 //
36 // Author: Andreas Schaelicke
37 //
38 // Creation date: 28.03.2008
39 //
40 // Modifications:
41 //
42 //
43 // Class Description:
44 //
45 // Implementation of energy loss for gamma emission by electrons and
46 // positrons including an improved version of the LPM effect
47 
48 // -------------------------------------------------------------------
49 //
50 
51 #ifndef G4eBremsstrahlungRelModel_h
52 #define G4eBremsstrahlungRelModel_h 1
53 
54 #include "G4VEmModel.hh"
55 #include "G4NistManager.hh"
56 #include "G4Exp.hh"
57 #include "G4Log.hh"
58 
60 class G4PhysicsVector;
61 
63 {
64 
65 public:
66 
68  const G4String& nam = "eBremLPM");
69 
71 
72  virtual void Initialise(const G4ParticleDefinition*, const G4DataVector&) override;
73 
74  virtual void InitialiseLocal(const G4ParticleDefinition*,
75  G4VEmModel* masterModel) override;
76 
78  const G4ParticleDefinition*,
79  G4double kineticEnergy,
80  G4double cutEnergy) override;
81 
83  G4double tkin,
85  G4double cutEnergy,
86  G4double maxEnergy = DBL_MAX) override;
87 
88  virtual void SampleSecondaries(std::vector<G4DynamicParticle*>*,
89  const G4MaterialCutsCouple*,
90  const G4DynamicParticle*,
91  G4double cutEnergy,
92  G4double maxEnergy) override;
93 
94  virtual void SetupForMaterial(const G4ParticleDefinition*,
95  const G4Material*,G4double) override;
96 
97  virtual G4double MinPrimaryEnergy(const G4Material*,
98  const G4ParticleDefinition*,
99  G4double cut) override;
100 
101  inline void SetLPMconstant(G4double val);
102  inline G4double LPMconstant() const;
103 
104  inline void SetLowestKinEnergy(G4double);
105  inline G4double LowestKinEnergy() const;
106 
107 
108 protected:
109 
110  virtual G4double ComputeDXSectionPerAtom(G4double gammaEnergy);
111 
112  // * fast inline functions *
113  inline void SetCurrentElement(G4int);
114 
115 private:
116 
117  void InitialiseConstants();
118 
119  void CalcLPMFunctions(G4double gammaEnergy);
120 
121  G4double ComputeBremLoss(G4double cutEnergy);
122 
123  G4double ComputeXSectionPerAtom(G4double cutEnergy);
124 
125  G4double ComputeRelDXSectionPerAtom(G4double gammaEnergy);
126 
127  void SetParticle(const G4ParticleDefinition* p);
128 
129  inline G4double Phi1(G4double,G4double);
130  inline G4double Phi1M2(G4double,G4double);
131  inline G4double Psi1(G4double,G4double);
132  inline G4double Psi1M2(G4double,G4double);
133 
134  // hide assignment operator
135  G4eBremsstrahlungRelModel & operator=(const G4eBremsstrahlungRelModel &right) = delete;
137 
138 protected:
139 
144 
146 
147  // cash
153 
156 
157 private:
158 
159  static const G4double xgi[8], wgi[8];
160  static const G4double Fel_light[5];
161  static const G4double Finel_light[5];
162 
163  // consts
164  G4double lowestKinEnergy;
165  G4double fMigdalConstant;
166  G4double fLPMconstant;
167  G4double energyThresholdLPM;
168  G4double facFel, facFinel;
169  G4double preS1,logTwo;
170 
171  // cash
172  G4double z13, z23, lnZ;
173  G4double Fel, Finel, fCoulomb, fMax;
174 
175  // LPM effect
176  G4double lpmEnergy;
177  G4double xiLPM, phiLPM, gLPM;
178 
179  // critical gamma energies
180  G4double klpm, kp;
181 
182  // flags
183  G4bool use_completescreening;
184 };
185 
186 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
187 
189 {
190  if(Z != currentZ) {
191  currentZ = Z;
192 
193  z13 = nist->GetZ13(Z);
194  z23 = z13*z13;
195  lnZ = nist->GetLOGZ(Z);
196 
197  if (Z <= 4) {
198  Fel = Fel_light[Z];
199  Finel = Finel_light[Z] ;
200  }
201  else {
202  G4double lnzt = lnZ/3.;
203  Fel = facFel - lnzt;
204  Finel = facFinel - 2*lnzt;
205  }
206 
207  fCoulomb = GetCurrentElement()->GetfCoulomb();
208  G4double xz = 1.0/(G4double)Z;
209  fMax = Fel-fCoulomb + Finel*xz + (1. + xz)/12.;
210  }
211 }
212 
213 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
214 
215 
216 inline G4double G4eBremsstrahlungRelModel::Phi1(G4double gg, G4double)
217 {
218  // Thomas-Fermi FF from Tsai, eq.(3.38) for Z>=5
219  return 20.863 - 2.*G4Log(1. + sqr(0.55846*gg) )
220  - 4.*( 1. - 0.6*G4Exp(-0.9*gg) - 0.4*G4Exp(-1.5*gg) );
221 }
222 
223 inline G4double G4eBremsstrahlungRelModel::Phi1M2(G4double gg, G4double)
224 {
225  // Thomas-Fermi FF from Tsai, eq. (3.39) for Z>=5
226  // return Phi1(gg,Z) -
227  return 2./(3.*(1. + 6.5*gg +6.*gg*gg) );
228 }
229 
230 inline G4double G4eBremsstrahlungRelModel::Psi1(G4double eps, G4double)
231 {
232  // Thomas-Fermi FF from Tsai, eq.(3.40) for Z>=5
233  return 28.340 - 2.*G4Log(1. + sqr(3.621*eps) )
234  - 4.*( 1. - 0.7*G4Exp(-8*eps) - 0.3*G4Exp(-29.*eps) );
235 }
236 
237 inline G4double G4eBremsstrahlungRelModel::Psi1M2(G4double eps, G4double)
238 {
239  // Thomas-Fermi FF from Tsai, eq. (3.41) for Z>=5
240  return 2./(3.*(1. + 40.*eps +400.*eps*eps) );
241 }
242 
243 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
244 
245 inline
247 {
248  fLPMconstant = val;
249 }
250 
251 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
252 
253 inline
255 {
256  return fLPMconstant;
257 }
258 
260 {
261  lowestKinEnergy = val;
262 }
263 
264 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
265 
267 {
268  return lowestKinEnergy;
269 }
270 
271 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
272 
273 
274 #endif
virtual void SampleSecondaries(std::vector< G4DynamicParticle * > *, const G4MaterialCutsCouple *, const G4DynamicParticle *, G4double cutEnergy, G4double maxEnergy) override
const char * p
Definition: xmltok.h:285
static const G4double eps
G4double GetfCoulomb() const
Definition: G4Element.hh:191
int G4int
Definition: G4Types.hh:78
const G4ParticleDefinition * particle
G4double GetZ13(G4double Z) const
virtual G4double MinPrimaryEnergy(const G4Material *, const G4ParticleDefinition *, G4double cut) override
bool G4bool
Definition: G4Types.hh:79
G4double GetLOGZ(G4int Z) const
G4eBremsstrahlungRelModel(const G4ParticleDefinition *p=0, const G4String &nam="eBremLPM")
G4double G4Log(G4double x)
Definition: G4Log.hh:230
G4double G4Exp(G4double initial_x)
Exponential Function double precision.
Definition: G4Exp.hh:183
virtual void Initialise(const G4ParticleDefinition *, const G4DataVector &) override
virtual void SetupForMaterial(const G4ParticleDefinition *, const G4Material *, G4double) override
virtual G4double ComputeDXSectionPerAtom(G4double gammaEnergy)
G4ParticleChangeForLoss * fParticleChange
T sqr(const T &x)
Definition: templates.hh:145
double G4double
Definition: G4Types.hh:76
virtual void InitialiseLocal(const G4ParticleDefinition *, G4VEmModel *masterModel) override
virtual G4double ComputeDEDXPerVolume(const G4Material *, const G4ParticleDefinition *, G4double kineticEnergy, G4double cutEnergy) override
#define DBL_MAX
Definition: templates.hh:83
virtual G4double ComputeCrossSectionPerAtom(const G4ParticleDefinition *, G4double tkin, G4double Z, G4double, G4double cutEnergy, G4double maxEnergy=DBL_MAX) override
const G4Element * GetCurrentElement() const
Definition: G4VEmModel.hh:469