source: trunk/source/processes/electromagnetic/standard/include/G4WentzelVIModel.hh @ 1058

Last change on this file since 1058 was 1055, checked in by garnier, 15 years ago

maj sur la beta de geant 4.9.3
File size: 8.3 KB
Line 
1//
2// ********************************************************************
3// * License and Disclaimer                                           *
4// *                                                                  *
5// * The  Geant4 software  is  copyright of the Copyright Holders  of *
6// * the Geant4 Collaboration.  It is provided  under  the terms  and *
7// * conditions of the Geant4 Software License,  included in the file *
8// * LICENSE and available at  http://cern.ch/geant4/license .  These *
9// * include a list of copyright holders.                             *
10// *                                                                  *
11// * Neither the authors of this software system, nor their employing *
12// * institutes,nor the agencies providing financial support for this *
13// * work  make  any representation or  warranty, express or implied, *
14// * regarding  this  software system or assume any liability for its *
15// * use.  Please see the license in the file  LICENSE  and URL above *
16// * for the full disclaimer and the limitation of liability.         *
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 *
22// * use  in  resulting  scientific  publications,  and indicate your *
23// * acceptance of all terms of the Geant4 Software license.          *
24// ********************************************************************
25//
26// $Id: G4WentzelVIModel.hh,v 1.17 2009/05/10 16:09:29 vnivanch 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:     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 G4ParticleDefinition;
69
70//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
71
72class G4WentzelVIModel : public G4VMscModel
73{
74
75public:
76
77  G4WentzelVIModel(const G4String& nam = "WentzelVIUni");
78
79  virtual ~G4WentzelVIModel();
80
81  virtual void Initialise(const G4ParticleDefinition*, const G4DataVector&);
82
83  virtual G4double ComputeCrossSectionPerAtom(const G4ParticleDefinition*,
84                                              G4double KineticEnergy,
85                                              G4double AtomicNumber,
86                                              G4double AtomicWeight=0., 
87                                              G4double cut = DBL_MAX,
88                                              G4double emax= DBL_MAX);
89
90  virtual void SampleScattering(const G4DynamicParticle*, G4double safety);
91
92  virtual G4double ComputeTruePathLengthLimit(const G4Track& track,
93                                              G4PhysicsTable* theLambdaTable,
94                                              G4double currentMinimalStep);
95
96  virtual G4double ComputeGeomPathLength(G4double truePathLength);
97
98  virtual G4double ComputeTrueStepLength(G4double geomStepLength);
99
100private:
101
102  G4double ComputeTransportXSectionPerAtom();
103
104  G4double ComputeXSectionPerVolume();
105
106  void ComputeMaxElectronScattering(G4double cut);
107
108  inline G4double GetLambda(G4double kinEnergy);
109
110  inline void SetupParticle(const G4ParticleDefinition*);
111
112  inline void SetupKinematic(G4double kinEnergy, G4double cut);
113 
114  inline void SetupTarget(G4double Z, G4double kinEnergy);
115
116  inline void DefineMaterial(const G4MaterialCutsCouple*);
117
118  //  hide assignment operator
119  G4WentzelVIModel & operator=(const  G4WentzelVIModel &right);
120  G4WentzelVIModel(const  G4WentzelVIModel&);
121
122  const G4ParticleDefinition* theProton;
123  const G4ParticleDefinition* theElectron;
124  const G4ParticleDefinition* thePositron;
125
126  G4ParticleChangeForMSC*   fParticleChange;
127
128  G4PhysicsTable*           theLambdaTable;
129  G4PhysicsTable*           theLambda2Table;
130  G4LossTableManager*       theManager;
131  const G4DataVector*       currentCuts;
132
133  G4NistManager*            fNistManager;
134
135  G4double numlimit;
136  G4double tlimitminfix;
137  G4double invsqrt12;
138
139  // cash
140  G4double preKinEnergy;
141  G4double ecut;
142  G4double lambda0;
143  G4double tPathLength;
144  G4double zPathLength;
145  G4double lambdaeff;
146  G4double currentRange; 
147  G4double par1;
148  G4double par2;
149  G4double par3;
150
151  G4double xtsec;
152  std::vector<G4double> xsecn;
153  std::vector<G4double> prob;
154  G4int    nelments;
155
156  G4int    nbins;
157  G4int    nwarnings;
158  G4int    nwarnlimit;
159
160  G4int    currentMaterialIndex;
161
162  const G4MaterialCutsCouple* currentCouple;
163  const G4Material* currentMaterial;
164
165  // single scattering parameters
166  G4double coeff;
167  G4double cosThetaMin;
168  G4double cosThetaMax;
169  G4double cosTetMaxNuc;
170  G4double cosTetMaxNuc2;
171  G4double cosTetMaxElec;
172  G4double cosTetMaxElec2;
173  G4double q2Limit;
174  G4double alpha2;
175
176  // projectile
177  const G4ParticleDefinition* particle;
178
179  G4double chargeSquare;
180  G4double spin;
181  G4double mass;
182  G4double tkin;
183  G4double mom2;
184  G4double invbeta2;
185  G4double kinFactor;
186  G4double etag;
187  G4double lowEnergyLimit;
188
189  // target
190  G4double targetZ;
191  G4double targetMass;
192  G4double screenZ;
193  G4double formfactA;
194  G4int    iz;
195
196  static G4double ScreenRSquare[100];
197  static G4double FormFactor[100];
198
199  // flags
200  G4bool   isInitialized;
201  G4bool   inside;
202};
203
204//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
205//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
206
207inline
208void G4WentzelVIModel::DefineMaterial(const G4MaterialCutsCouple* cup) 
209{ 
210  if(cup != currentCouple) {
211    currentCouple = cup;
212    currentMaterial = cup->GetMaterial();
213    currentMaterialIndex = currentCouple->GetIndex(); 
214  }
215}
216
217//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
218
219inline
220G4double G4WentzelVIModel::GetLambda(G4double e)
221{
222  G4double x;
223  if(theLambdaTable) {
224    G4bool b;
225    x = ((*theLambdaTable)[currentMaterialIndex])->GetValue(e, b);
226  } else {
227    x = CrossSection(currentCouple,particle,e,
228                     (*currentCuts)[currentMaterialIndex]);
229  }
230  if(x > DBL_MIN) x = 1./x;
231  else            x = DBL_MAX;
232  return x;
233}
234
235//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
236
237inline void G4WentzelVIModel::SetupParticle(const G4ParticleDefinition* p)
238{
239  // Initialise mass and charge
240  if(p != particle) {
241    particle = p;
242    mass = particle->GetPDGMass();
243    spin = particle->GetPDGSpin();
244    G4double q = particle->GetPDGCharge()/eplus;
245    chargeSquare = q*q;
246    tkin = 0.0;
247  }
248}
249
250//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
251
252inline void G4WentzelVIModel::SetupKinematic(G4double ekin, G4double cut)
253{
254  if(ekin != tkin || ecut != cut) {
255    tkin  = ekin;
256    mom2  = tkin*(tkin + 2.0*mass);
257    invbeta2 = 1.0 +  mass*mass/mom2;
258    cosTetMaxNuc = cosThetaMax;
259    if(mass < MeV && ekin <= 10.*cut) {
260      cosTetMaxNuc = ekin*(cosThetaMax + 1.0)/(10.*cut) - 1.0;
261    }
262    ComputeMaxElectronScattering(cut);
263  } 
264}
265
266//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
267 
268inline void G4WentzelVIModel::SetupTarget(G4double Z, G4double e)
269{
270  if(Z != targetZ || e != etag) {
271    etag    = e; 
272    targetZ = Z;
273    iz = G4int(Z);
274    if(iz > 99) iz = 99;
275    targetMass = fNistManager->GetAtomicMassAmu(iz)*amu_c2;
276    G4double m12  = mass*mass;
277    G4double x    = 1.0 + mass/targetMass;
278    kinFactor  = coeff*targetZ*chargeSquare*(1.0 +  m12/mom2)/mom2;
279    screenZ = ScreenRSquare[iz]/mom2;
280    if(iz > 1) {
281      screenZ *=(1.13 + 3.76*Z*Z*alpha2);
282      kinFactor /= (x*x);
283    }
284    //if(iz > 1) screenZ *=(1.13 + std::min(0.5,3.76*Z*Z*invbeta2*alpha2));
285    formfactA = FormFactor[iz]*mom2;
286    cosTetMaxNuc2 = cosTetMaxNuc;
287    cosTetMaxElec2 = cosTetMaxElec;
288  } 
289} 
290
291//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
292
293#endif
294
Note: See TracBrowser for help on using the repository browser.