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>> 26 // $Id: G4mplIonisationModel.cc 91869 2015-08-07 15:21:02Z gcosmo $
26 // 27 //
27 // ------------------------------------------- 28 // -------------------------------------------------------------------
28 // 29 //
29 // GEANT4 Class header file 30 // GEANT4 Class header file
30 // 31 //
31 // 32 //
32 // File name: G4mplIonisationModel 33 // File name: G4mplIonisationModel
33 // 34 //
34 // Author: Vladimir Ivanchenko 35 // Author: Vladimir Ivanchenko
35 // 36 //
36 // Creation date: 06.09.2005 37 // Creation date: 06.09.2005
37 // 38 //
38 // Modifications: 39 // Modifications:
39 // 12.08.2007 Changing low energy approximatio 40 // 12.08.2007 Changing low energy approximation and extrapolation.
40 // Small bug fixing and refactoring 41 // Small bug fixing and refactoring (M. Vladymyrov)
41 // 13.11.2007 Use low-energy asymptotic from [ 42 // 13.11.2007 Use low-energy asymptotic from [3] (V.Ivanchenko)
42 // 43 //
43 // 44 //
44 // ------------------------------------------- 45 // -------------------------------------------------------------------
45 // References 46 // References
46 // [1] Steven P. Ahlen: Energy loss of relativ 47 // [1] Steven P. Ahlen: Energy loss of relativistic heavy ionizing particles,
47 // S.P. Ahlen, Rev. Mod. Phys 52(1980), p1 48 // S.P. Ahlen, Rev. Mod. Phys 52(1980), p121
48 // [2] K.A. Milton arXiv:hep-ex/0602040 49 // [2] K.A. Milton arXiv:hep-ex/0602040
49 // [3] S.P. Ahlen and K. Kinoshita, Phys. Rev. 50 // [3] S.P. Ahlen and K. Kinoshita, Phys. Rev. D26 (1982) 2347
50 51
51 52
52 //....oooOO0OOooo........oooOO0OOooo........oo 53 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
53 //....oooOO0OOooo........oooOO0OOooo........oo 54 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
54 55
55 #include "G4mplIonisationModel.hh" 56 #include "G4mplIonisationModel.hh"
56 #include "Randomize.hh" 57 #include "Randomize.hh"
57 #include "G4PhysicalConstants.hh" 58 #include "G4PhysicalConstants.hh"
58 #include "G4SystemOfUnits.hh" 59 #include "G4SystemOfUnits.hh"
59 #include "G4ParticleChangeForLoss.hh" 60 #include "G4ParticleChangeForLoss.hh"
60 #include "G4ProductionCutsTable.hh" 61 #include "G4ProductionCutsTable.hh"
61 #include "G4MaterialCutsCouple.hh" 62 #include "G4MaterialCutsCouple.hh"
62 #include "G4Log.hh" 63 #include "G4Log.hh"
63 #include "G4Pow.hh" <<
64 64
65 //....oooOO0OOooo........oooOO0OOooo........oo 65 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
66 66
67 std::vector<G4double>* G4mplIonisationModel::d << 67 using namespace std;
>> 68
>> 69 std::vector<G4double>* G4mplIonisationModel::dedx0 = 0;
68 70
69 G4mplIonisationModel::G4mplIonisationModel(G4d 71 G4mplIonisationModel::G4mplIonisationModel(G4double mCharge, const G4String& nam)
70 : G4VEmModel(nam),G4VEmFluctuationModel(nam) 72 : G4VEmModel(nam),G4VEmFluctuationModel(nam),
71 magCharge(mCharge), 73 magCharge(mCharge),
72 twoln10(G4Log(100.0)), << 74 twoln10(log(100.0)),
73 betalow(0.01), 75 betalow(0.01),
74 betalim(0.1), 76 betalim(0.1),
75 beta2lim(betalim*betalim), 77 beta2lim(betalim*betalim),
76 bg2lim(beta2lim*(1.0 + beta2lim)) 78 bg2lim(beta2lim*(1.0 + beta2lim))
77 { 79 {
78 nmpl = G4int(std::abs(magCharge) * 2 * CLHEP << 80 nmpl = G4int(abs(magCharge) * 2 * fine_structure_const + 0.5);
79 if(nmpl > 6) { nmpl = 6; } 81 if(nmpl > 6) { nmpl = 6; }
80 else if(nmpl < 1) { nmpl = 1; } 82 else if(nmpl < 1) { nmpl = 1; }
81 pi_hbarc2_over_mc2 = CLHEP::pi*CLHEP::hbarc* << 83 pi_hbarc2_over_mc2 = pi * hbarc * hbarc / electron_mass_c2;
82 chargeSquare = magCharge * magCharge; 84 chargeSquare = magCharge * magCharge;
83 dedxlim = 45.*nmpl*nmpl*CLHEP::GeV*CLHEP::cm << 85 dedxlim = 45.*nmpl*nmpl*GeV*cm2/g;
>> 86 fParticleChange = 0;
>> 87 monopole = 0;
>> 88 mass = 0.0;
84 } 89 }
85 90
86 //....oooOO0OOooo........oooOO0OOooo........oo 91 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
87 92
88 G4mplIonisationModel::~G4mplIonisationModel() 93 G4mplIonisationModel::~G4mplIonisationModel()
89 { 94 {
90 if(IsMaster()) { delete dedx0; } 95 if(IsMaster()) { delete dedx0; }
91 } 96 }
92 97
93 //....oooOO0OOooo........oooOO0OOooo........oo 98 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
94 99
95 void G4mplIonisationModel::SetParticle(const G 100 void G4mplIonisationModel::SetParticle(const G4ParticleDefinition* p)
96 { 101 {
97 monopole = p; 102 monopole = p;
98 mass = monopole->GetPDGMass(); 103 mass = monopole->GetPDGMass();
99 G4double emin = 104 G4double emin =
100 std::min(LowEnergyLimit(),0.1*mass*(1./std << 105 std::min(LowEnergyLimit(),0.1*mass*(1/sqrt(1 - betalow*betalow) - 1));
101 G4double emax = 106 G4double emax =
102 std::max(HighEnergyLimit(),10.*mass*(1./st << 107 std::max(HighEnergyLimit(),10*mass*(1/sqrt(1 - beta2lim) - 1));
103 SetLowEnergyLimit(emin); 108 SetLowEnergyLimit(emin);
104 SetHighEnergyLimit(emax); 109 SetHighEnergyLimit(emax);
105 } 110 }
106 111
107 //....oooOO0OOooo........oooOO0OOooo........oo 112 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
108 113
109 void G4mplIonisationModel::Initialise(const G4 114 void G4mplIonisationModel::Initialise(const G4ParticleDefinition* p,
110 const G4DataVector&) 115 const G4DataVector&)
111 { 116 {
112 if(nullptr == monopole) { SetParticle(p); } << 117 if(!monopole) { SetParticle(p); }
113 if(nullptr == fParticleChange) { fParticleCh << 118 if(!fParticleChange) { fParticleChange = GetParticleChangeForLoss(); }
114 if(IsMaster()) { 119 if(IsMaster()) {
115 if(nullptr == dedx0) { dedx0 = new std::ve << 120 if(!dedx0) { dedx0 = new std::vector<G4double>; }
116 G4ProductionCutsTable* theCoupleTable= 121 G4ProductionCutsTable* theCoupleTable=
117 G4ProductionCutsTable::GetProductionCuts 122 G4ProductionCutsTable::GetProductionCutsTable();
118 G4int numOfCouples = (G4int)theCoupleTable << 123 G4int numOfCouples = theCoupleTable->GetTableSize();
119 G4int n = (G4int)dedx0->size(); << 124 G4int n = dedx0->size();
120 if(n < numOfCouples) { dedx0->resize(numOf 125 if(n < numOfCouples) { dedx0->resize(numOfCouples); }
121 126
122 G4Pow* g4calc = G4Pow::GetInstance(); << 127 // initialise vector
123 <<
124 // initialise vector assuming low conducti <<
125 for(G4int i=0; i<numOfCouples; ++i) { 128 for(G4int i=0; i<numOfCouples; ++i) {
126 129
127 const G4Material* material = 130 const G4Material* material =
128 theCoupleTable->GetMaterialCutsCouple( << 131 theCoupleTable->GetMaterialCutsCouple(i)->GetMaterial();
129 G4double eDensity = material->GetElectro 132 G4double eDensity = material->GetElectronDensity();
130 G4double vF2 = 2*electron_Compton_length << 133 G4double vF = electron_Compton_length*pow(3*pi*pi*eDensity,0.3333333333);
131 (*dedx0)[i] = pi_hbarc2_over_mc2*eDensit 134 (*dedx0)[i] = pi_hbarc2_over_mc2*eDensity*nmpl*nmpl*
132 (G4Log(vF2/fine_structure_const) - 0.5 << 135 (G4Log(2*vF/fine_structure_const) - 0.5)/vF;
133 } 136 }
134 } 137 }
135 } 138 }
136 139
137 //....oooOO0OOooo........oooOO0OOooo........oo 140 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
138 141
139 G4double G4mplIonisationModel::ComputeDEDXPerV 142 G4double G4mplIonisationModel::ComputeDEDXPerVolume(const G4Material* material,
140 const G4ParticleDefinition* p, 143 const G4ParticleDefinition* p,
141 G4double kineticEnergy, 144 G4double kineticEnergy,
142 G4double) 145 G4double)
143 { 146 {
144 if(nullptr == monopole) { SetParticle(p); } << 147 if(!monopole) { SetParticle(p); }
145 G4double tau = kineticEnergy / mass; 148 G4double tau = kineticEnergy / mass;
146 G4double gam = tau + 1.0; 149 G4double gam = tau + 1.0;
147 G4double bg2 = tau * (tau + 2.0); 150 G4double bg2 = tau * (tau + 2.0);
148 G4double beta2 = bg2 / (gam * gam); 151 G4double beta2 = bg2 / (gam * gam);
149 G4double beta = std::sqrt(beta2); << 152 G4double beta = sqrt(beta2);
150 153
151 // low-energy asymptotic formula 154 // low-energy asymptotic formula
152 //G4double dedx = dedxlim*beta*material->Ge 155 //G4double dedx = dedxlim*beta*material->GetDensity();
153 G4double dedx = (*dedx0)[CurrentCouple()->Ge 156 G4double dedx = (*dedx0)[CurrentCouple()->GetIndex()]*beta;
154 157
155 // above asymptotic 158 // above asymptotic
156 if(beta > betalow) { 159 if(beta > betalow) {
157 160
158 // high energy 161 // high energy
159 if(beta >= betalim) { 162 if(beta >= betalim) {
160 dedx = ComputeDEDXAhlen(material, bg2); 163 dedx = ComputeDEDXAhlen(material, bg2);
161 164
162 } else { 165 } else {
163 166
164 //G4double dedx1 = dedxlim*betalow*mater 167 //G4double dedx1 = dedxlim*betalow*material->GetDensity();
165 G4double dedx1 = (*dedx0)[CurrentCouple( 168 G4double dedx1 = (*dedx0)[CurrentCouple()->GetIndex()]*betalow;
166 G4double dedx2 = ComputeDEDXAhlen(materi 169 G4double dedx2 = ComputeDEDXAhlen(material, bg2lim);
167 170
168 // extrapolation between two formula 171 // extrapolation between two formula
169 G4double kapa2 = beta - betalow; 172 G4double kapa2 = beta - betalow;
170 G4double kapa1 = betalim - beta; 173 G4double kapa1 = betalim - beta;
171 dedx = (kapa1*dedx1 + kapa2*dedx2)/(kapa 174 dedx = (kapa1*dedx1 + kapa2*dedx2)/(kapa1 + kapa2);
172 } 175 }
173 } 176 }
174 return dedx; 177 return dedx;
175 } 178 }
176 179
177 //....oooOO0OOooo........oooOO0OOooo........oo 180 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
178 181
179 G4double G4mplIonisationModel::ComputeDEDXAhle 182 G4double G4mplIonisationModel::ComputeDEDXAhlen(const G4Material* material,
180 G4double bg2) 183 G4double bg2)
181 { 184 {
182 G4double eDensity = material->GetElectronDen 185 G4double eDensity = material->GetElectronDensity();
183 G4double eexc = material->GetIonisation()-> 186 G4double eexc = material->GetIonisation()->GetMeanExcitationEnergy();
184 G4double cden = material->GetIonisation()-> 187 G4double cden = material->GetIonisation()->GetCdensity();
185 G4double mden = material->GetIonisation()-> 188 G4double mden = material->GetIonisation()->GetMdensity();
186 G4double aden = material->GetIonisation()-> 189 G4double aden = material->GetIonisation()->GetAdensity();
187 G4double x0den = material->GetIonisation()-> 190 G4double x0den = material->GetIonisation()->GetX0density();
188 G4double x1den = material->GetIonisation()-> 191 G4double x1den = material->GetIonisation()->GetX1density();
189 192
190 // Ahlen's formula for nonconductors, [1]p15 193 // Ahlen's formula for nonconductors, [1]p157, f(5.7)
191 G4double dedx = std::log(2.0 * electron_mass << 194 G4double dedx = log(2.0 * electron_mass_c2 * bg2 / eexc) - 0.5;
192 195
193 // Kazama et al. cross-section correction 196 // Kazama et al. cross-section correction
194 G4double k = 0.406; 197 G4double k = 0.406;
195 if(nmpl > 1) k = 0.346; 198 if(nmpl > 1) k = 0.346;
196 199
197 // Bloch correction 200 // Bloch correction
198 const G4double B[7] = { 0.0, 0.248, 0.672, 1 201 const G4double B[7] = { 0.0, 0.248, 0.672, 1.022, 1.243, 1.464, 1.685};
199 202
200 dedx += 0.5 * k - B[nmpl]; 203 dedx += 0.5 * k - B[nmpl];
201 204
202 // density effect correction 205 // density effect correction
203 G4double deltam; 206 G4double deltam;
204 G4double x = std::log(bg2) / twoln10; << 207 G4double x = log(bg2) / twoln10;
205 if ( x >= x0den ) { 208 if ( x >= x0den ) {
206 deltam = twoln10 * x - cden; 209 deltam = twoln10 * x - cden;
207 if ( x < x1den ) deltam += aden * std::pow << 210 if ( x < x1den ) deltam += aden * pow((x1den-x), mden);
208 dedx -= 0.5 * deltam; 211 dedx -= 0.5 * deltam;
209 } 212 }
210 213
211 // now compute the total ionization loss 214 // now compute the total ionization loss
212 dedx *= pi_hbarc2_over_mc2 * eDensity * nmp 215 dedx *= pi_hbarc2_over_mc2 * eDensity * nmpl * nmpl;
213 216
214 if (dedx < 0.0) dedx = 0.; << 217 if (dedx < 0.0) dedx = 0;
215 return dedx; 218 return dedx;
216 } 219 }
217 220
218 //....oooOO0OOooo........oooOO0OOooo........oo 221 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
219 222
220 void G4mplIonisationModel::SampleSecondaries(s 223 void G4mplIonisationModel::SampleSecondaries(std::vector<G4DynamicParticle*>*,
221 const G4MaterialCutsCouple*, 224 const G4MaterialCutsCouple*,
222 const G4DynamicParticle*, 225 const G4DynamicParticle*,
223 G4double, 226 G4double,
224 G4double) 227 G4double)
225 {} 228 {}
226 229
227 //....oooOO0OOooo........oooOO0OOooo........oo 230 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
228 231
229 G4double G4mplIonisationModel::SampleFluctuati 232 G4double G4mplIonisationModel::SampleFluctuations(
230 const G4MaterialCutsCouple* cou 233 const G4MaterialCutsCouple* couple,
231 const G4DynamicParticle* dp, 234 const G4DynamicParticle* dp,
232 const G << 235 G4double tmax,
233 const G << 236 G4double length,
234 const G4double length, << 237 G4double meanLoss)
235 const G4double meanLoss) <<
236 { 238 {
237 G4double siga = Dispersion(couple->GetMateri << 239 G4double siga = Dispersion(couple->GetMaterial(),dp,tmax,length);
238 G4double loss = meanLoss; 240 G4double loss = meanLoss;
239 siga = std::sqrt(siga); << 241 siga = sqrt(siga);
240 G4double twomeanLoss = meanLoss + meanLoss; 242 G4double twomeanLoss = meanLoss + meanLoss;
241 243
242 if(twomeanLoss < siga) { 244 if(twomeanLoss < siga) {
243 G4double x; 245 G4double x;
244 do { 246 do {
245 loss = twomeanLoss*G4UniformRand(); 247 loss = twomeanLoss*G4UniformRand();
246 x = (loss - meanLoss)/siga; 248 x = (loss - meanLoss)/siga;
247 // Loop checking, 07-Aug-2015, Vladimir 249 // Loop checking, 07-Aug-2015, Vladimir Ivanchenko
248 } while (1.0 - 0.5*x*x < G4UniformRand()); 250 } while (1.0 - 0.5*x*x < G4UniformRand());
249 } else { 251 } else {
250 do { 252 do {
251 loss = G4RandGauss::shoot(meanLoss,siga) 253 loss = G4RandGauss::shoot(meanLoss,siga);
252 // Loop checking, 07-Aug-2015, Vladimir 254 // Loop checking, 07-Aug-2015, Vladimir Ivanchenko
253 } while (0.0 > loss || loss > twomeanLoss) 255 } while (0.0 > loss || loss > twomeanLoss);
254 } 256 }
255 return loss; 257 return loss;
256 } 258 }
257 259
258 //....oooOO0OOooo........oooOO0OOooo........oo 260 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
259 261
260 G4double G4mplIonisationModel::Dispersion(cons 262 G4double G4mplIonisationModel::Dispersion(const G4Material* material,
261 const G4DynamicParticle* dp, 263 const G4DynamicParticle* dp,
262 const G4double tcut, << 264 G4double tmax,
263 const G4double tmax, << 265 G4double length)
264 const G4double length) <<
265 { 266 {
266 G4double siga = 0.0; 267 G4double siga = 0.0;
267 G4double tau = dp->GetKineticEnergy()/mass 268 G4double tau = dp->GetKineticEnergy()/mass;
268 if(tau > 0.0) { 269 if(tau > 0.0) {
269 const G4double beta = dp->GetBeta(); << 270 G4double electronDensity = material->GetElectronDensity();
270 siga = (tmax/(beta*beta) - 0.5*tcut) * tw << 271 G4double gam = tau + 1.0;
271 * material->GetElectronDensity() * charg << 272 G4double invbeta2 = (gam*gam)/(tau * (tau+2.0));
>> 273 siga = (invbeta2 - 0.5) * twopi_mc2_rcl2 * tmax * length
>> 274 * electronDensity * chargeSquare;
272 } 275 }
273 return siga; 276 return siga;
274 } 277 }
275 278
276 //....oooOO0OOooo........oooOO0OOooo........oo 279 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
277 280