| Geant4 Cross Reference |
1 // 1 //
2 // ******************************************* 2 // ********************************************************************
3 // * License and Disclaimer 3 // * License and Disclaimer *
4 // * 4 // * *
5 // * The Geant4 software is copyright of th 5 // * The Geant4 software is copyright of the Copyright Holders of *
6 // * the Geant4 Collaboration. It is provided 6 // * the Geant4 Collaboration. It is provided under the terms and *
7 // * conditions of the Geant4 Software License 7 // * conditions of the Geant4 Software License, included in the file *
8 // * LICENSE and available at http://cern.ch/ 8 // * LICENSE and available at http://cern.ch/geant4/license . These *
9 // * include a list of copyright holders. 9 // * include a list of copyright holders. *
10 // * 10 // * *
11 // * Neither the authors of this software syst 11 // * Neither the authors of this software system, nor their employing *
12 // * institutes,nor the agencies providing fin 12 // * institutes,nor the agencies providing financial support for this *
13 // * work make any representation or warran 13 // * work make any representation or warranty, express or implied, *
14 // * regarding this software system or assum 14 // * regarding this software system or assume any liability for its *
15 // * use. Please see the license in the file 15 // * use. Please see the license in the file LICENSE and URL above *
16 // * for the full disclaimer and the limitatio 16 // * for the full disclaimer and the limitation of liability. *
17 // * 17 // * *
18 // * This code implementation is the result 18 // * This code implementation is the result of the scientific and *
19 // * technical work of the GEANT4 collaboratio 19 // * technical work of the GEANT4 collaboration. *
20 // * By using, copying, modifying or distri 20 // * By using, copying, modifying or distributing the software (or *
21 // * any work based on the software) you ag 21 // * any work based on the software) you agree to acknowledge its *
22 // * use in resulting scientific publicati 22 // * use in resulting scientific publications, and indicate your *
23 // * acceptance of all terms of the Geant4 Sof 23 // * acceptance of all terms of the Geant4 Software license. *
24 // ******************************************* 24 // ********************************************************************
25 // 25 //
>> 26 // $Id: G4mplIonisationModel.cc,v 1.8 2010-10-26 15:40:03 vnivanch Exp $
>> 27 // GEANT4 tag $Name: geant4-09-04-patch-02 $
26 // 28 //
27 // ------------------------------------------- 29 // -------------------------------------------------------------------
28 // 30 //
29 // GEANT4 Class header file 31 // GEANT4 Class header file
30 // 32 //
31 // 33 //
32 // File name: G4mplIonisationModel 34 // File name: G4mplIonisationModel
33 // 35 //
34 // Author: Vladimir Ivanchenko 36 // Author: Vladimir Ivanchenko
35 // 37 //
36 // Creation date: 06.09.2005 38 // Creation date: 06.09.2005
37 // 39 //
38 // Modifications: 40 // Modifications:
39 // 12.08.2007 Changing low energy approximatio 41 // 12.08.2007 Changing low energy approximation and extrapolation.
40 // Small bug fixing and refactoring 42 // Small bug fixing and refactoring (M. Vladymyrov)
41 // 13.11.2007 Use low-energy asymptotic from [ 43 // 13.11.2007 Use low-energy asymptotic from [3] (V.Ivanchenko)
42 // 44 //
43 // 45 //
44 // ------------------------------------------- 46 // -------------------------------------------------------------------
45 // References 47 // References
46 // [1] Steven P. Ahlen: Energy loss of relativ 48 // [1] Steven P. Ahlen: Energy loss of relativistic heavy ionizing particles,
47 // S.P. Ahlen, Rev. Mod. Phys 52(1980), p1 49 // S.P. Ahlen, Rev. Mod. Phys 52(1980), p121
48 // [2] K.A. Milton arXiv:hep-ex/0602040 50 // [2] K.A. Milton arXiv:hep-ex/0602040
49 // [3] S.P. Ahlen and K. Kinoshita, Phys. Rev. 51 // [3] S.P. Ahlen and K. Kinoshita, Phys. Rev. D26 (1982) 2347
50 52
51 53
52 //....oooOO0OOooo........oooOO0OOooo........oo 54 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
53 //....oooOO0OOooo........oooOO0OOooo........oo 55 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
54 56
55 #include "G4mplIonisationModel.hh" 57 #include "G4mplIonisationModel.hh"
56 #include "Randomize.hh" 58 #include "Randomize.hh"
57 #include "G4PhysicalConstants.hh" << 59 #include "G4LossTableManager.hh"
58 #include "G4SystemOfUnits.hh" <<
59 #include "G4ParticleChangeForLoss.hh" 60 #include "G4ParticleChangeForLoss.hh"
60 #include "G4ProductionCutsTable.hh" <<
61 #include "G4MaterialCutsCouple.hh" <<
62 #include "G4Log.hh" <<
63 #include "G4Pow.hh" <<
64 61
65 //....oooOO0OOooo........oooOO0OOooo........oo 62 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
66 63
67 std::vector<G4double>* G4mplIonisationModel::d << 64 using namespace std;
68 65
69 G4mplIonisationModel::G4mplIonisationModel(G4d 66 G4mplIonisationModel::G4mplIonisationModel(G4double mCharge, const G4String& nam)
70 : G4VEmModel(nam),G4VEmFluctuationModel(nam) 67 : G4VEmModel(nam),G4VEmFluctuationModel(nam),
71 magCharge(mCharge), 68 magCharge(mCharge),
72 twoln10(G4Log(100.0)), << 69 twoln10(log(100.0)),
73 betalow(0.01), 70 betalow(0.01),
74 betalim(0.1), 71 betalim(0.1),
75 beta2lim(betalim*betalim), 72 beta2lim(betalim*betalim),
76 bg2lim(beta2lim*(1.0 + beta2lim)) 73 bg2lim(beta2lim*(1.0 + beta2lim))
77 { 74 {
78 nmpl = G4int(std::abs(magCharge) * 2 * CLHEP << 75 nmpl = G4int(abs(magCharge) * 2 * fine_structure_const + 0.5);
79 if(nmpl > 6) { nmpl = 6; } 76 if(nmpl > 6) { nmpl = 6; }
80 else if(nmpl < 1) { nmpl = 1; } 77 else if(nmpl < 1) { nmpl = 1; }
81 pi_hbarc2_over_mc2 = CLHEP::pi*CLHEP::hbarc* << 78 pi_hbarc2_over_mc2 = pi * hbarc * hbarc / electron_mass_c2;
82 chargeSquare = magCharge * magCharge; 79 chargeSquare = magCharge * magCharge;
83 dedxlim = 45.*nmpl*nmpl*CLHEP::GeV*CLHEP::cm << 80 dedxlim = 45.*nmpl*nmpl*GeV*cm2/g;
>> 81 fParticleChange = 0;
>> 82 mass = 0.0;
84 } 83 }
85 84
86 //....oooOO0OOooo........oooOO0OOooo........oo 85 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
87 86
88 G4mplIonisationModel::~G4mplIonisationModel() 87 G4mplIonisationModel::~G4mplIonisationModel()
89 { << 88 {}
90 if(IsMaster()) { delete dedx0; } <<
91 } <<
92 <<
93 //....oooOO0OOooo........oooOO0OOooo........oo <<
94 <<
95 void G4mplIonisationModel::SetParticle(const G <<
96 { <<
97 monopole = p; <<
98 mass = monopole->GetPDGMass(); <<
99 G4double emin = <<
100 std::min(LowEnergyLimit(),0.1*mass*(1./std <<
101 G4double emax = <<
102 std::max(HighEnergyLimit(),10.*mass*(1./st <<
103 SetLowEnergyLimit(emin); <<
104 SetHighEnergyLimit(emax); <<
105 } <<
106 89
107 //....oooOO0OOooo........oooOO0OOooo........oo 90 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
108 91
109 void G4mplIonisationModel::Initialise(const G4 92 void G4mplIonisationModel::Initialise(const G4ParticleDefinition* p,
110 const G4DataVector&) 93 const G4DataVector&)
111 { 94 {
112 if(nullptr == monopole) { SetParticle(p); } << 95 monopole = p;
113 if(nullptr == fParticleChange) { fParticleCh << 96 mass = monopole->GetPDGMass();
114 if(IsMaster()) { << 97 if(!fParticleChange) { fParticleChange = GetParticleChangeForLoss(); }
115 if(nullptr == dedx0) { dedx0 = new std::ve <<
116 G4ProductionCutsTable* theCoupleTable= <<
117 G4ProductionCutsTable::GetProductionCuts <<
118 G4int numOfCouples = (G4int)theCoupleTable <<
119 G4int n = (G4int)dedx0->size(); <<
120 if(n < numOfCouples) { dedx0->resize(numOf <<
121 <<
122 G4Pow* g4calc = G4Pow::GetInstance(); <<
123 <<
124 // initialise vector assuming low conducti <<
125 for(G4int i=0; i<numOfCouples; ++i) { <<
126 <<
127 const G4Material* material = <<
128 theCoupleTable->GetMaterialCutsCouple( <<
129 G4double eDensity = material->GetElectro <<
130 G4double vF2 = 2*electron_Compton_length <<
131 (*dedx0)[i] = pi_hbarc2_over_mc2*eDensit <<
132 (G4Log(vF2/fine_structure_const) - 0.5 <<
133 } <<
134 } <<
135 } 98 }
136 99
137 //....oooOO0OOooo........oooOO0OOooo........oo 100 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
138 101
139 G4double G4mplIonisationModel::ComputeDEDXPerV 102 G4double G4mplIonisationModel::ComputeDEDXPerVolume(const G4Material* material,
140 const G4ParticleDefinition* p, << 103 const G4ParticleDefinition*,
141 G4double kineticEnergy, 104 G4double kineticEnergy,
142 G4double) 105 G4double)
143 { 106 {
144 if(nullptr == monopole) { SetParticle(p); } <<
145 G4double tau = kineticEnergy / mass; 107 G4double tau = kineticEnergy / mass;
146 G4double gam = tau + 1.0; 108 G4double gam = tau + 1.0;
147 G4double bg2 = tau * (tau + 2.0); 109 G4double bg2 = tau * (tau + 2.0);
148 G4double beta2 = bg2 / (gam * gam); 110 G4double beta2 = bg2 / (gam * gam);
149 G4double beta = std::sqrt(beta2); << 111 G4double beta = sqrt(beta2);
150 112
151 // low-energy asymptotic formula 113 // low-energy asymptotic formula
152 //G4double dedx = dedxlim*beta*material->Ge << 114 G4double dedx = dedxlim*beta*material->GetDensity();
153 G4double dedx = (*dedx0)[CurrentCouple()->Ge <<
154 115
155 // above asymptotic 116 // above asymptotic
156 if(beta > betalow) { 117 if(beta > betalow) {
157 118
158 // high energy 119 // high energy
159 if(beta >= betalim) { 120 if(beta >= betalim) {
160 dedx = ComputeDEDXAhlen(material, bg2); 121 dedx = ComputeDEDXAhlen(material, bg2);
161 122
162 } else { 123 } else {
163 124
164 //G4double dedx1 = dedxlim*betalow*mater << 125 G4double dedx1 = dedxlim*betalow*material->GetDensity();
165 G4double dedx1 = (*dedx0)[CurrentCouple( <<
166 G4double dedx2 = ComputeDEDXAhlen(materi 126 G4double dedx2 = ComputeDEDXAhlen(material, bg2lim);
167 127
168 // extrapolation between two formula 128 // extrapolation between two formula
169 G4double kapa2 = beta - betalow; 129 G4double kapa2 = beta - betalow;
170 G4double kapa1 = betalim - beta; 130 G4double kapa1 = betalim - beta;
171 dedx = (kapa1*dedx1 + kapa2*dedx2)/(kapa 131 dedx = (kapa1*dedx1 + kapa2*dedx2)/(kapa1 + kapa2);
172 } 132 }
173 } 133 }
174 return dedx; 134 return dedx;
175 } 135 }
176 136
177 //....oooOO0OOooo........oooOO0OOooo........oo 137 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
178 138
179 G4double G4mplIonisationModel::ComputeDEDXAhle 139 G4double G4mplIonisationModel::ComputeDEDXAhlen(const G4Material* material,
180 G4double bg2) 140 G4double bg2)
181 { 141 {
182 G4double eDensity = material->GetElectronDen 142 G4double eDensity = material->GetElectronDensity();
183 G4double eexc = material->GetIonisation()-> 143 G4double eexc = material->GetIonisation()->GetMeanExcitationEnergy();
184 G4double cden = material->GetIonisation()-> 144 G4double cden = material->GetIonisation()->GetCdensity();
185 G4double mden = material->GetIonisation()-> 145 G4double mden = material->GetIonisation()->GetMdensity();
186 G4double aden = material->GetIonisation()-> 146 G4double aden = material->GetIonisation()->GetAdensity();
187 G4double x0den = material->GetIonisation()-> 147 G4double x0den = material->GetIonisation()->GetX0density();
188 G4double x1den = material->GetIonisation()-> 148 G4double x1den = material->GetIonisation()->GetX1density();
189 149
190 // Ahlen's formula for nonconductors, [1]p15 150 // Ahlen's formula for nonconductors, [1]p157, f(5.7)
191 G4double dedx = std::log(2.0 * electron_mass << 151 G4double dedx = log(2.0 * electron_mass_c2 * bg2 / eexc) - 0.5;
192 152
193 // Kazama et al. cross-section correction 153 // Kazama et al. cross-section correction
194 G4double k = 0.406; 154 G4double k = 0.406;
195 if(nmpl > 1) k = 0.346; 155 if(nmpl > 1) k = 0.346;
196 156
197 // Bloch correction 157 // Bloch correction
198 const G4double B[7] = { 0.0, 0.248, 0.672, 1 158 const G4double B[7] = { 0.0, 0.248, 0.672, 1.022, 1.243, 1.464, 1.685};
199 159
200 dedx += 0.5 * k - B[nmpl]; 160 dedx += 0.5 * k - B[nmpl];
201 161
202 // density effect correction 162 // density effect correction
203 G4double deltam; 163 G4double deltam;
204 G4double x = std::log(bg2) / twoln10; << 164 G4double x = log(bg2) / twoln10;
205 if ( x >= x0den ) { 165 if ( x >= x0den ) {
206 deltam = twoln10 * x - cden; 166 deltam = twoln10 * x - cden;
207 if ( x < x1den ) deltam += aden * std::pow << 167 if ( x < x1den ) deltam += aden * pow((x1den-x), mden);
208 dedx -= 0.5 * deltam; 168 dedx -= 0.5 * deltam;
209 } 169 }
210 170
211 // now compute the total ionization loss 171 // now compute the total ionization loss
212 dedx *= pi_hbarc2_over_mc2 * eDensity * nmp 172 dedx *= pi_hbarc2_over_mc2 * eDensity * nmpl * nmpl;
213 173
214 if (dedx < 0.0) dedx = 0.; << 174 if (dedx < 0.0) dedx = 0;
215 return dedx; 175 return dedx;
216 } 176 }
217 177
218 //....oooOO0OOooo........oooOO0OOooo........oo 178 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
219 179
220 void G4mplIonisationModel::SampleSecondaries(s 180 void G4mplIonisationModel::SampleSecondaries(std::vector<G4DynamicParticle*>*,
221 const G4MaterialCutsCouple*, 181 const G4MaterialCutsCouple*,
222 const G4DynamicParticle*, 182 const G4DynamicParticle*,
223 G4double, 183 G4double,
224 G4double) 184 G4double)
225 {} 185 {}
226 186
227 //....oooOO0OOooo........oooOO0OOooo........oo 187 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
228 188
229 G4double G4mplIonisationModel::SampleFluctuati 189 G4double G4mplIonisationModel::SampleFluctuations(
230 const G4MaterialCutsCouple* cou << 190 const G4Material* material,
231 const G4DynamicParticle* dp, 191 const G4DynamicParticle* dp,
232 const G << 192 G4double& tmax,
233 const G << 193 G4double& length,
234 const G4double length, << 194 G4double& meanLoss)
235 const G4double meanLoss) <<
236 { 195 {
237 G4double siga = Dispersion(couple->GetMateri << 196 G4double siga = Dispersion(material,dp,tmax,length);
238 G4double loss = meanLoss; 197 G4double loss = meanLoss;
239 siga = std::sqrt(siga); << 198 siga = sqrt(siga);
240 G4double twomeanLoss = meanLoss + meanLoss; 199 G4double twomeanLoss = meanLoss + meanLoss;
241 200
242 if(twomeanLoss < siga) { 201 if(twomeanLoss < siga) {
243 G4double x; 202 G4double x;
244 do { 203 do {
245 loss = twomeanLoss*G4UniformRand(); 204 loss = twomeanLoss*G4UniformRand();
246 x = (loss - meanLoss)/siga; 205 x = (loss - meanLoss)/siga;
247 // Loop checking, 07-Aug-2015, Vladimir <<
248 } while (1.0 - 0.5*x*x < G4UniformRand()); 206 } while (1.0 - 0.5*x*x < G4UniformRand());
249 } else { 207 } else {
250 do { 208 do {
251 loss = G4RandGauss::shoot(meanLoss,siga) 209 loss = G4RandGauss::shoot(meanLoss,siga);
252 // Loop checking, 07-Aug-2015, Vladimir <<
253 } while (0.0 > loss || loss > twomeanLoss) 210 } while (0.0 > loss || loss > twomeanLoss);
254 } 211 }
255 return loss; 212 return loss;
256 } 213 }
257 214
258 //....oooOO0OOooo........oooOO0OOooo........oo 215 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
259 216
260 G4double G4mplIonisationModel::Dispersion(cons 217 G4double G4mplIonisationModel::Dispersion(const G4Material* material,
261 const G4DynamicParticle* dp, 218 const G4DynamicParticle* dp,
262 const G4double tcut, << 219 G4double& tmax,
263 const G4double tmax, << 220 G4double& length)
264 const G4double length) <<
265 { 221 {
266 G4double siga = 0.0; 222 G4double siga = 0.0;
267 G4double tau = dp->GetKineticEnergy()/mass 223 G4double tau = dp->GetKineticEnergy()/mass;
268 if(tau > 0.0) { 224 if(tau > 0.0) {
269 const G4double beta = dp->GetBeta(); << 225 G4double electronDensity = material->GetElectronDensity();
270 siga = (tmax/(beta*beta) - 0.5*tcut) * tw << 226 G4double gam = tau + 1.0;
271 * material->GetElectronDensity() * charg << 227 G4double invbeta2 = (gam*gam)/(tau * (tau+2.0));
>> 228 siga = (invbeta2 - 0.5) * twopi_mc2_rcl2 * tmax * length
>> 229 * electronDensity * chargeSquare;
272 } 230 }
273 return siga; 231 return siga;
274 } 232 }
275 233
276 //....oooOO0OOooo........oooOO0OOooo........oo 234 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
277 235