source: trunk/source/processes/electromagnetic/standard/include/G4UrbanMscModel2.hh@ 1192

Last change on this file since 1192 was 1055, checked in by garnier, 17 years ago

maj sur la beta de geant 4.9.3
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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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11// * Neither the authors of this software system, nor their employing *
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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 *
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22// * use in resulting scientific publications, and indicate your *
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24// ********************************************************************
25//
26// $Id: G4UrbanMscModel2.hh,v 1.17 2009/05/15 09:26:42 urban Exp $
27// GEANT4 tag $Name: geant4-09-03-beta-cand-01 $
28//
29// -------------------------------------------------------------------
30//
31//
32// GEANT4 Class header file
33//
34//
35// File name: G4UrbanMscModel2
36//
37// Author: Laszlo Urban
38//
39// Creation date: 06.03.2008
40//
41// Modifications:
42// 23.04.2009 L.Urban updated parameterization in UpdateCache method
43//
44//
45// Class Description:
46//
47// Implementation of the model of multiple scattering based on
48// H.W.Lewis Phys Rev 78 (1950) 526 and L.Urban model
49
50// -------------------------------------------------------------------
51//
52
53#ifndef G4UrbanMscModel2_h
54#define G4UrbanMscModel2_h 1
55
56//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
57
58#include "G4VMscModel.hh"
59#include "G4PhysicsTable.hh"
60#include "G4MscStepLimitType.hh"
61
62class G4ParticleChangeForMSC;
63class G4SafetyHelper;
64class G4LossTableManager;
65
66//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
67
68class G4UrbanMscModel2 : public G4VMscModel
69{
70
71public:
72
73 G4UrbanMscModel2(const G4String& nam = "UrbanMscUni2");
74
75 virtual ~G4UrbanMscModel2();
76
77 void Initialise(const G4ParticleDefinition*, const G4DataVector&);
78
79 G4double ComputeCrossSectionPerAtom(const G4ParticleDefinition* particle,
80 G4double KineticEnergy,
81 G4double AtomicNumber,
82 G4double AtomicWeight=0.,
83 G4double cut =0.,
84 G4double emax=DBL_MAX);
85
86 void SampleScattering(const G4DynamicParticle*,
87 G4double safety);
88
89 G4double ComputeTruePathLengthLimit(const G4Track& track,
90 G4PhysicsTable* theLambdaTable,
91 G4double currentMinimalStep);
92
93 G4double ComputeGeomPathLength(G4double truePathLength);
94
95 G4double ComputeTrueStepLength(G4double geomStepLength);
96
97 G4double ComputeTheta0(G4double truePathLength,
98 G4double KineticEnergy);
99
100private:
101
102 G4double SimpleScattering(G4double xmeanth, G4double x2meanth);
103
104 G4double SampleCosineTheta(G4double trueStepLength, G4double KineticEnergy);
105
106 G4double SampleDisplacement();
107
108 G4double LatCorrelation();
109
110 inline G4double GetLambda(G4double kinEnergy);
111
112 inline void SetParticle(const G4ParticleDefinition*);
113
114 inline void UpdateCache();
115
116 // hide assignment operator
117 G4UrbanMscModel2 & operator=(const G4UrbanMscModel2 &right);
118 G4UrbanMscModel2(const G4UrbanMscModel2&);
119
120 const G4ParticleDefinition* particle;
121 G4ParticleChangeForMSC* fParticleChange;
122
123 G4PhysicsTable* theLambdaTable;
124 const G4MaterialCutsCouple* couple;
125 G4LossTableManager* theManager;
126
127 G4double mass;
128 G4double charge,ChargeSquare;
129 G4double masslimite,lambdalimit,fr;
130
131 G4double taubig;
132 G4double tausmall;
133 G4double taulim;
134 G4double currentTau;
135 G4double tlimit;
136 G4double tlimitmin;
137 G4double tlimitminfix;
138 G4double tgeom;
139
140 G4double geombig;
141 G4double geommin;
142 G4double geomlimit;
143 G4double skindepth;
144 G4double smallstep;
145
146 G4double presafety;
147
148 G4double lambda0;
149 G4double lambdaeff;
150 G4double tPathLength;
151 G4double zPathLength;
152 G4double par1,par2,par3;
153
154 G4double stepmin;
155
156 G4double currentKinEnergy;
157 G4double currentRange;
158 G4double rangeinit;
159 G4double currentRadLength;
160
161 G4double theta0max,rellossmax;
162 G4double third;
163
164 G4int currentMaterialIndex;
165
166 G4double y;
167 G4double Zold;
168 G4double Zeff,Z2,Z23,lnZ;
169 G4double coeffth1,coeffth2;
170 G4double coeffc1,coeffc2;
171 G4double scr1ini,scr2ini,scr1,scr2;
172
173 G4bool isInitialized;
174 G4bool inside;
175 G4bool insideskin;
176};
177
178//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
179//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
180
181inline
182G4double G4UrbanMscModel2::GetLambda(G4double e)
183{
184 G4double x;
185 if(theLambdaTable) {
186 G4bool b;
187 x = ((*theLambdaTable)[currentMaterialIndex])->GetValue(e, b);
188 } else {
189 x = CrossSection(couple,particle,e);
190 }
191 if(x > DBL_MIN) x = 1./x;
192 else x = DBL_MAX;
193 return x;
194}
195
196//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
197
198inline
199void G4UrbanMscModel2::SetParticle(const G4ParticleDefinition* p)
200{
201 if (p != particle) {
202 particle = p;
203 mass = p->GetPDGMass();
204 charge = p->GetPDGCharge()/eplus;
205 ChargeSquare = charge*charge;
206 }
207}
208
209//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
210
211inline
212void G4UrbanMscModel2::UpdateCache()
213{
214 lnZ = std::log(Zeff);
215 //new correction in theta0 formula
216 coeffth1 = (1.-8.7780e-2/Zeff)*(0.87+0.03*lnZ);
217 coeffth2 = (4.0780e-2+1.7315e-4*Zeff)*(0.87+0.03*lnZ);
218 // tail parameters
219 G4double lnZ1 = std::log(Zeff+1.);
220 coeffc1 = 2.943-0.197*lnZ1;
221 coeffc2 = 0.0987-0.0143*lnZ1;
222 // for single scattering
223 Z2 = Zeff*Zeff;
224 Z23 = std::exp(2.*lnZ/3.);
225 scr1 = scr1ini*Z23;
226 scr2 = scr2ini*Z2*ChargeSquare;
227
228 Zold = Zeff;
229}
230
231#endif
232
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