source: trunk/source/processes/electromagnetic/standard/include/G4WentzelVIModel.hh@ 1036

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

update to geant4.9.2
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1//
2// ********************************************************************
3// * License and Disclaimer *
4// * *
5// * The Geant4 software is copyright of the Copyright Holders of *
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7// * conditions of the Geant4 Software License, included in the file *
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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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17// * *
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 *
21// * any work based on the software) you agree to acknowledge its *
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24// ********************************************************************
25//
26// $Id: G4WentzelVIModel.hh,v 1.7 2008/08/04 08:49:09 vnivanch Exp $
27// GEANT4 tag $Name: geant4-09-02 $
28//
29// -------------------------------------------------------------------
30//
31//
32// GEANT4 Class header file
33//
34//
35// File name: G4WentzelVIModel
36//
37// Author: V.Ivanchenko
38//
39// Creation date: 09.04.2008 from G4MuMscModel
40//
41// Modifications:
42//
43//
44// Class Description:
45//
46// Implementation of the model of multiple scattering based on
47// G.Wentzel, Z. Phys. 40 (1927) 590.
48// H.W.Lewis, Phys Rev 78 (1950) 526.
49// J.M. Fernandez-Varea et al., NIM B73 (1993) 447.
50// L.Urban, CERN-OPEN-2006-077.
51
52// -------------------------------------------------------------------
53//
54
55#ifndef G4WentzelVIModel_h
56#define G4WentzelVIModel_h 1
57
58//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
59
60#include "G4VMscModel.hh"
61#include "G4PhysicsTable.hh"
62#include "G4MscStepLimitType.hh"
63#include "G4MaterialCutsCouple.hh"
64#include "G4NistManager.hh"
65
66class G4LossTableManager;
67class G4ParticleChangeForMSC;
68class G4SafetyHelper;
69class G4ParticleDefinition;
70
71//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
72
73class G4WentzelVIModel : public G4VMscModel
74{
75
76public:
77
78 G4WentzelVIModel(const G4String& nam = "WentzelVIUni");
79
80 virtual ~G4WentzelVIModel();
81
82 void Initialise(const G4ParticleDefinition*, const G4DataVector&);
83
84 G4double ComputeCrossSectionPerAtom(const G4ParticleDefinition*,
85 G4double KineticEnergy,
86 G4double AtomicNumber,
87 G4double AtomicWeight=0.,
88 G4double cut = DBL_MAX,
89 G4double emax= DBL_MAX);
90
91 void SampleScattering(const G4DynamicParticle*, G4double safety);
92
93 void SampleSecondaries(std::vector<G4DynamicParticle*>*,
94 const G4MaterialCutsCouple*,
95 const G4DynamicParticle*,
96 G4double,
97 G4double);
98
99 G4double ComputeTruePathLengthLimit(const G4Track& track,
100 G4PhysicsTable* theLambdaTable,
101 G4double currentMinimalStep);
102
103 G4double ComputeGeomPathLength(G4double truePathLength);
104
105 G4double ComputeTrueStepLength(G4double geomStepLength);
106
107private:
108
109 G4double ComputeTransportXSectionPerVolume();
110
111 G4double ComputeXSectionPerVolume();
112
113 void ComputeMaxElectronScattering(G4double cut);
114
115 inline G4double GetLambda(G4double kinEnergy);
116
117 inline void SetupParticle(const G4ParticleDefinition*);
118
119 inline void SetupKinematic(G4double kinEnergy, G4double cut);
120
121 inline void SetupTarget(G4double Z, G4double kinEnergy);
122
123 inline void DefineMaterial(const G4MaterialCutsCouple*);
124
125 // hide assignment operator
126 G4WentzelVIModel & operator=(const G4WentzelVIModel &right);
127 G4WentzelVIModel(const G4WentzelVIModel&);
128
129 const G4ParticleDefinition* theProton;
130 const G4ParticleDefinition* theElectron;
131 const G4ParticleDefinition* thePositron;
132
133 G4ParticleChangeForMSC* fParticleChange;
134
135 G4SafetyHelper* safetyHelper;
136 G4PhysicsTable* theLambdaTable;
137 G4PhysicsTable* theLambda2Table;
138 G4LossTableManager* theManager;
139 const G4DataVector* currentCuts;
140
141 G4NistManager* fNistManager;
142
143 G4double numlimit;
144 G4double tlimitminfix;
145 G4double invsqrt12;
146
147 // cash
148 G4double preKinEnergy;
149 G4double ecut;
150 G4double lambda0;
151 G4double tPathLength;
152 G4double zPathLength;
153 G4double lambdaeff;
154 G4double currentRange;
155 G4double par1;
156 G4double par2;
157 G4double par3;
158
159 G4double xtsec;
160 std::vector<G4double> xsecn;
161 std::vector<G4double> prob;
162 G4int nelments;
163
164 G4int nbins;
165 G4int nwarnings;
166 G4int nwarnlimit;
167
168 G4int currentMaterialIndex;
169
170 const G4MaterialCutsCouple* currentCouple;
171 const G4Material* currentMaterial;
172
173 // single scattering parameters
174 G4double coeff;
175 G4double constn;
176 G4double cosThetaMin;
177 G4double cosThetaMax;
178 G4double cosTetMaxNuc;
179 G4double cosTetMaxNuc2;
180 G4double cosTetMaxElec;
181 G4double cosTetMaxElec2;
182 G4double q2Limit;
183 G4double alpha2;
184 G4double a0;
185
186 // projectile
187 const G4ParticleDefinition* particle;
188
189 G4double chargeSquare;
190 G4double spin;
191 G4double mass;
192 G4double tkin;
193 G4double mom2;
194 G4double invbeta2;
195 G4double etag;
196 G4double lowEnergyLimit;
197
198 // target
199 G4double targetZ;
200 G4double screenZ;
201 G4double formfactA;
202 G4double FF[100];
203
204 // flags
205 G4bool isInitialized;
206 G4bool inside;
207};
208
209//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
210//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
211
212inline
213void G4WentzelVIModel::DefineMaterial(const G4MaterialCutsCouple* cup)
214{
215 if(cup != currentCouple) {
216 currentCouple = cup;
217 currentMaterial = cup->GetMaterial();
218 currentMaterialIndex = currentCouple->GetIndex();
219 }
220}
221
222//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
223
224inline
225G4double G4WentzelVIModel::GetLambda(G4double e)
226{
227 G4double x;
228 if(theLambdaTable) {
229 G4bool b;
230 x = ((*theLambdaTable)[currentMaterialIndex])->GetValue(e, b);
231 } else {
232 x = CrossSection(currentCouple,particle,e,
233 (*currentCuts)[currentMaterialIndex]);
234 }
235 if(x > DBL_MIN) x = 1./x;
236 else x = DBL_MAX;
237 return x;
238}
239
240//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
241
242inline
243void G4WentzelVIModel::SetupParticle(const G4ParticleDefinition* p)
244{
245 // Initialise mass and charge
246 if(p != particle) {
247 particle = p;
248 mass = particle->GetPDGMass();
249 spin = particle->GetPDGSpin();
250 G4double q = particle->GetPDGCharge()/eplus;
251 chargeSquare = q*q;
252 tkin = 0.0;
253 lowEnergyLimit = keV*mass/electron_mass_c2;
254 }
255}
256
257//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
258
259inline void G4WentzelVIModel::SetupKinematic(G4double ekin, G4double cut)
260{
261 if(ekin != tkin || ecut != cut) {
262 tkin = ekin;
263 mom2 = tkin*(tkin + 2.0*mass);
264 invbeta2 = 1.0 + mass*mass/mom2;
265 cosTetMaxNuc = cosThetaMax;
266 if(ekin <= 10.*cut && mass < MeV) {
267 cosTetMaxNuc = ekin*(cosThetaMax + 1.0)/(10.*cut) - 1.0;
268 }
269 ComputeMaxElectronScattering(cut);
270 }
271}
272
273//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
274
275inline void G4WentzelVIModel::SetupTarget(G4double Z, G4double e)
276{
277 if(Z != targetZ || e != etag) {
278 etag = e;
279 targetZ = Z;
280 G4int iz= G4int(Z);
281 if(iz > 99) iz = 99;
282 G4double x = fNistManager->GetZ13(iz);
283 screenZ = a0*x*x/mom2;
284 if(iz > 1) screenZ *=(1.13 + 3.76*invbeta2*Z*Z*chargeSquare*alpha2);
285 // screenZ = a0*x*x*(1.13 + 3.76*Z*Z*chargeSquare*alpha2)/mom2;
286 // A.V. Butkevich et al., NIM A 488 (2002) 282
287 formfactA = FF[iz];
288 if(formfactA == 0.0) {
289 x = fNistManager->GetA27(iz);
290 formfactA = constn*x*x;
291 FF[iz] = formfactA;
292 }
293 formfactA *= mom2;
294 cosTetMaxNuc2 = cosTetMaxNuc;
295 /*
296 G4double ee = 10.*eV*Z;
297 if(1 == iz) ee *= 2.0;
298 G4double z = std::min(cosTetMaxElec, 1.0 - std::max(ecut,ee)*amu_c2
299 *fNistManager->GetAtomicMassAmu(iz)/mom2);
300 cosTetMaxElec2 = std::max(cosTetMaxNuc2, z);
301 */
302 cosTetMaxElec2 = cosTetMaxElec;
303 }
304}
305
306//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
307
308#endif
309
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