source: trunk/source/processes/electromagnetic/standard/include/G4eCoulombScatteringModel.hh@ 960

Last change on this file since 960 was 819, checked in by garnier, 17 years ago

import all except CVS
File size: 7.5 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: G4eCoulombScatteringModel.hh,v 1.20 2007/10/24 10:42:05 vnivanch Exp $
27// GEANT4 tag $Name: geant4-09-01-patch-02 $
28//
29// -------------------------------------------------------------------
30//
31// GEANT4 Class header file
32//
33//
34// File name: G4eCoulombScatteringModel
35//
36// Author: Vladimir Ivanchenko
37//
38// Creation date: 19.02.2006
39//
40// Modifications:
41// 01.08.06 V.Ivanchenko extend upper limit of table to TeV and review the
42// logic of building - only elements from G4ElementTable
43// 08.08.06 V.Ivanchenko build internal table in ekin scale, introduce faclim
44// 19.08.06 V.Ivanchenko add inline function ScreeningParameter and
45// make some members protected
46// 09.10.07 V.Ivanchenko reorganized methods, add cut dependence in scattering off e-
47//
48// Class Description:
49//
50// Implementation of eCoulombScattering of pointlike charge particle
51// on Atomic Nucleus for interval of scattering anles in Lab system
52// thetaMin - ThetaMax, nucleus recoil is neglected.
53// The model based on analysis of J.M.Fernandez-Varea et al.
54// NIM B73(1993)447 originated from G.Wentzel Z.Phys. 40(1927)590 with
55// screening parameter from H.A.Bethe Phys. Rev. 89 (1953) 1256.
56//
57
58// -------------------------------------------------------------------
59//
60
61#ifndef G4eCoulombScatteringModel_h
62#define G4eCoulombScatteringModel_h 1
63
64#include "G4VEmModel.hh"
65#include "G4PhysicsTable.hh"
66#include "G4NistManager.hh"
67#include "globals.hh"
68
69class G4ParticleChangeForGamma;
70class G4ParticleDefinition;
71
72class G4eCoulombScatteringModel : public G4VEmModel
73{
74
75public:
76
77 G4eCoulombScatteringModel(G4double thetaMin = 0.0, G4double thetaMax = pi,
78 G4bool build = false, G4double tlim = TeV*TeV,
79 const G4String& nam = "eCoulombScattering");
80
81 virtual ~G4eCoulombScatteringModel();
82
83 virtual void Initialise(const G4ParticleDefinition*, const G4DataVector&);
84
85 virtual G4double ComputeCrossSectionPerAtom(
86 const G4ParticleDefinition*,
87 G4double kinEnergy,
88 G4double Z,
89 G4double A,
90 G4double cut,
91 G4double emax);
92
93 virtual void SampleSecondaries(std::vector<G4DynamicParticle*>*,
94 const G4MaterialCutsCouple*,
95 const G4DynamicParticle*,
96 G4double tmin,
97 G4double maxEnergy);
98
99protected:
100
101 G4double ComputeElectronXSectionPerAtom(
102 const G4ParticleDefinition*,
103 G4double kinEnergy,
104 G4double Z,
105 G4double A,
106 G4double cut);
107
108 virtual G4double CalculateCrossSectionPerAtom(
109 const G4ParticleDefinition*,
110 G4double kinEnergy,
111 G4double Z, G4double A);
112
113 inline void SetupParticle(const G4ParticleDefinition*);
114
115 inline void SetupKinematic(G4double kinEnergy);
116
117 inline void SetupTarget(G4double Z, G4double A, G4double kinEnergy);
118
119private:
120
121 // hide assignment operator
122 G4eCoulombScatteringModel & operator=(const G4eCoulombScatteringModel &right);
123 G4eCoulombScatteringModel(const G4eCoulombScatteringModel&);
124
125protected:
126
127 const G4ParticleDefinition* theProton;
128 const G4ParticleDefinition* theElectron;
129 const G4ParticleDefinition* thePositron;
130
131 G4ParticleChangeForGamma* fParticleChange;
132 G4NistManager* fNistManager;
133
134 G4double coeff;
135 G4double constn;
136 G4double cosThetaMin;
137 G4double cosThetaMax;
138 G4double cosTetMaxNuc;
139 G4double cosTetMaxElec;
140 G4double q2Limit;
141 G4double elecXSection;
142 G4double nucXSection;
143 G4double ecut;
144
145 // projectile
146 const G4ParticleDefinition* particle;
147
148 G4double chargeSquare;
149 G4double spin;
150 G4double mass;
151 G4double tkin;
152 G4double mom2;
153 G4double invbeta2;
154
155 // target
156 G4double targetZ;
157 G4double targetA;
158 G4double screenZ;
159 G4double formfactA;
160
161private:
162
163 G4PhysicsTable* theCrossSectionTable;
164
165 G4double a0;
166 G4double lowKEnergy;
167 G4double highKEnergy;
168 G4double alpha2;
169 G4double faclim;
170
171 G4int nbins;
172 G4int nmax;
173 G4int index[100];
174
175 G4bool buildTable;
176 G4bool isInitialised;
177};
178
179//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
180
181inline
182void G4eCoulombScatteringModel::SetupParticle(const G4ParticleDefinition* p)
183{
184 // Initialise mass and charge
185 if(p != particle) {
186 particle = p;
187 mass = particle->GetPDGMass();
188 spin = particle->GetPDGSpin();
189 G4double q = particle->GetPDGCharge()/eplus;
190 chargeSquare = q*q;
191 tkin = 0.0;
192 }
193}
194
195//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
196
197inline void G4eCoulombScatteringModel::SetupKinematic(G4double ekin)
198{
199 if(ekin != tkin) {
200 tkin = ekin;
201 mom2 = tkin*(tkin + 2.0*mass);
202 invbeta2 = 1.0 + mass*mass/mom2;
203 }
204}
205
206//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
207
208inline void G4eCoulombScatteringModel::SetupTarget(G4double Z, G4double A,
209 G4double e)
210{
211 if(e != tkin || Z != targetZ || A != targetA) {
212 targetZ = Z;
213 targetA = A;
214 SetupKinematic(e);
215 cosTetMaxNuc = std::max(cosThetaMax, 1.0 - 0.5*q2Limit/mom2);
216 G4double x = fNistManager->GetZ13(Z);
217 screenZ = a0*x*x*(1.13 + 3.76*invbeta2*Z*Z*chargeSquare*alpha2)/mom2;
218 if(particle == theProton && A < 1.5 && cosTetMaxNuc < 0.0)
219 cosTetMaxNuc = 0.0;
220 // A.V. Butkevich et al., NIM A 488 (2002) 282
221 x = fNistManager->GetLOGA(A);
222 formfactA = mom2*constn*std::exp(0.54*x);
223 }
224}
225
226//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
227
228#endif
Note: See TracBrowser for help on using the repository browser.