| 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 1.3 2006/12/13 15:44:27 gunter Exp $
>> 27 // GEANT4 tag $Name: geant4-08-02 $
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 <<
40 // Small bug fixing and refactoring <<
41 // 13.11.2007 Use low-energy asymptotic from [ <<
42 // 41 //
43 // 42 //
44 // ------------------------------------------- 43 // -------------------------------------------------------------------
45 // References << 44 //
46 // [1] Steven P. Ahlen: Energy loss of relativ <<
47 // S.P. Ahlen, Rev. Mod. Phys 52(1980), p1 <<
48 // [2] K.A. Milton arXiv:hep-ex/0602040 <<
49 // [3] S.P. Ahlen and K. Kinoshita, Phys. Rev. <<
50 45
51 46
52 //....oooOO0OOooo........oooOO0OOooo........oo 47 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
53 //....oooOO0OOooo........oooOO0OOooo........oo 48 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
54 49
55 #include "G4mplIonisationModel.hh" 50 #include "G4mplIonisationModel.hh"
56 #include "Randomize.hh" 51 #include "Randomize.hh"
57 #include "G4PhysicalConstants.hh" << 52 #include "G4LossTableManager.hh"
58 #include "G4SystemOfUnits.hh" <<
59 #include "G4ParticleChangeForLoss.hh" 53 #include "G4ParticleChangeForLoss.hh"
60 #include "G4ProductionCutsTable.hh" <<
61 #include "G4MaterialCutsCouple.hh" <<
62 #include "G4Log.hh" <<
63 #include "G4Pow.hh" <<
64 54
65 //....oooOO0OOooo........oooOO0OOooo........oo 55 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
66 56
67 std::vector<G4double>* G4mplIonisationModel::d << 57 using namespace std;
68 58
69 G4mplIonisationModel::G4mplIonisationModel(G4d << 59 G4mplIonisationModel::G4mplIonisationModel(G4double mCharge,
>> 60 const G4String& nam)
70 : G4VEmModel(nam),G4VEmFluctuationModel(nam) 61 : G4VEmModel(nam),G4VEmFluctuationModel(nam),
71 magCharge(mCharge), 62 magCharge(mCharge),
72 twoln10(G4Log(100.0)), << 63 twoln10(2.0*log(10.0)),
73 betalow(0.01), << 64 beta2low(0.0001),
74 betalim(0.1), << 65 beta2lim(0.01),
75 beta2lim(betalim*betalim), <<
76 bg2lim(beta2lim*(1.0 + beta2lim)) 66 bg2lim(beta2lim*(1.0 + beta2lim))
77 { 67 {
78 nmpl = G4int(std::abs(magCharge) * 2 * CLHEP << 68 nmpl = G4int(abs(magCharge)/68.0);
79 if(nmpl > 6) { nmpl = 6; } << 69 if(nmpl > 6) nmpl = 6;
80 else if(nmpl < 1) { nmpl = 1; } << 70 else if(nmpl < 1) nmpl = 1;
81 pi_hbarc2_over_mc2 = CLHEP::pi*CLHEP::hbarc* << 71 G4double x = 45.0*GeV*G4double(nmpl)/cm;
82 chargeSquare = magCharge * magCharge; << 72 factlow = x*x;
83 dedxlim = 45.*nmpl*nmpl*CLHEP::GeV*CLHEP::cm << 73 chargeSquare = magCharge*magCharge;
84 } 74 }
85 75
86 //....oooOO0OOooo........oooOO0OOooo........oo 76 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
87 77
88 G4mplIonisationModel::~G4mplIonisationModel() 78 G4mplIonisationModel::~G4mplIonisationModel()
89 { << 79 {}
90 if(IsMaster()) { delete dedx0; } <<
91 } <<
92 80
93 //....oooOO0OOooo........oooOO0OOooo........oo 81 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
94 82
95 void G4mplIonisationModel::SetParticle(const G << 83 void G4mplIonisationModel::Initialise(const G4ParticleDefinition* p,
>> 84 const G4DataVector&)
96 { 85 {
97 monopole = p; 86 monopole = p;
98 mass = monopole->GetPDGMass(); 87 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 <<
107 //....oooOO0OOooo........oooOO0OOooo........oo <<
108 88
109 void G4mplIonisationModel::Initialise(const G4 << 89 if(pParticleChange)
110 const G4DataVector&) << 90 fParticleChange = reinterpret_cast<G4ParticleChangeForLoss*>(pParticleChange);
111 { << 91 else
112 if(nullptr == monopole) { SetParticle(p); } << 92 fParticleChange = new G4ParticleChangeForLoss();
113 if(nullptr == fParticleChange) { fParticleCh <<
114 if(IsMaster()) { <<
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 } 93 }
136 94
137 //....oooOO0OOooo........oooOO0OOooo........oo 95 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
138 96
139 G4double G4mplIonisationModel::ComputeDEDXPerV 97 G4double G4mplIonisationModel::ComputeDEDXPerVolume(const G4Material* material,
140 const G4ParticleDefinition* p, << 98 const G4ParticleDefinition*,
141 G4double kineticEnergy, 99 G4double kineticEnergy,
142 G4double) 100 G4double)
143 { 101 {
144 if(nullptr == monopole) { SetParticle(p); } << 102 G4double tau = kineticEnergy/mass;
145 G4double tau = kineticEnergy / mass; <<
146 G4double gam = tau + 1.0; 103 G4double gam = tau + 1.0;
147 G4double bg2 = tau * (tau + 2.0); << 104 G4double bg2 = tau * (tau+2.0);
148 G4double beta2 = bg2 / (gam * gam); << 105 G4double beta2 = bg2/(gam*gam);
149 G4double beta = std::sqrt(beta2); << 106
150 << 107 G4double dedx0 = factlow*abs(beta2);
151 // low-energy asymptotic formula << 108
152 //G4double dedx = dedxlim*beta*material->Ge << 109 if(beta2 > beta2low) {
153 G4double dedx = (*dedx0)[CurrentCouple()->Ge << 110
154 << 111 G4double b2 = beta2;
155 // above asymptotic << 112 if(beta2 < beta2lim) {
156 if(beta > betalow) { << 113 beta2= beta2lim;
157 << 114 bg2 = bg2lim;
158 // high energy <<
159 if(beta >= betalim) { <<
160 dedx = ComputeDEDXAhlen(material, bg2); <<
161 <<
162 } else { <<
163 <<
164 //G4double dedx1 = dedxlim*betalow*mater <<
165 G4double dedx1 = (*dedx0)[CurrentCouple( <<
166 G4double dedx2 = ComputeDEDXAhlen(materi <<
167 <<
168 // extrapolation between two formula <<
169 G4double kapa2 = beta - betalow; <<
170 G4double kapa1 = betalim - beta; <<
171 dedx = (kapa1*dedx1 + kapa2*dedx2)/(kapa <<
172 } 115 }
173 } <<
174 return dedx; <<
175 } <<
176 116
177 //....oooOO0OOooo........oooOO0OOooo........oo << 117 G4double eexc = material->GetIonisation()->GetMeanExcitationEnergy();
>> 118 G4double cden = material->GetIonisation()->GetCdensity();
>> 119 G4double mden = material->GetIonisation()->GetMdensity();
>> 120 G4double aden = material->GetIonisation()->GetAdensity();
>> 121 G4double x0den = material->GetIonisation()->GetX0density();
>> 122 G4double x1den = material->GetIonisation()->GetX1density();
>> 123
>> 124 G4double eDensity = material->GetElectronDensity();
>> 125
>> 126 G4double dedx = 2.0*log(2.0*electron_mass_c2*bg2/eexc) - 1.0;
>> 127
>> 128 G4double k = 0.406;
>> 129 if(nmpl > 1) k = 0.346;
>> 130 const G4double B[7] = { 0.0, 0.248, 0.672, 1.022, 1.243, 1.464, 1.685};
>> 131
>> 132 dedx += k - B[nmpl];
>> 133
>> 134 // density correction
>> 135 G4double x = log(bg2)/twoln10;
>> 136 if ( x >= x0den ) {
>> 137 dedx -= twoln10*x - cden ;
>> 138 if ( x < x1den ) dedx -= aden*pow((x1den-x),mden) ;
>> 139 }
178 140
179 G4double G4mplIonisationModel::ComputeDEDXAhle << 141 // now compute the total ionization loss
180 G4double bg2) <<
181 { <<
182 G4double eDensity = material->GetElectronDen <<
183 G4double eexc = material->GetIonisation()-> <<
184 G4double cden = material->GetIonisation()-> <<
185 G4double mden = material->GetIonisation()-> <<
186 G4double aden = material->GetIonisation()-> <<
187 G4double x0den = material->GetIonisation()-> <<
188 G4double x1den = material->GetIonisation()-> <<
189 <<
190 // Ahlen's formula for nonconductors, [1]p15 <<
191 G4double dedx = std::log(2.0 * electron_mass <<
192 <<
193 // Kazama et al. cross-section correction <<
194 G4double k = 0.406; <<
195 if(nmpl > 1) k = 0.346; <<
196 <<
197 // Bloch correction <<
198 const G4double B[7] = { 0.0, 0.248, 0.672, 1 <<
199 <<
200 dedx += 0.5 * k - B[nmpl]; <<
201 <<
202 // density effect correction <<
203 G4double deltam; <<
204 G4double x = std::log(bg2) / twoln10; <<
205 if ( x >= x0den ) { <<
206 deltam = twoln10 * x - cden; <<
207 if ( x < x1den ) deltam += aden * std::pow <<
208 dedx -= 0.5 * deltam; <<
209 } <<
210 142
211 // now compute the total ionization loss << 143 if (dedx < 0.0) dedx = 0.0 ;
212 dedx *= pi_hbarc2_over_mc2 * eDensity * nmp <<
213 144
214 if (dedx < 0.0) dedx = 0.; << 145 dedx *= twopi_mc2_rcl2*chargeSquare*eDensity;
215 return dedx; <<
216 } <<
217 146
218 //....oooOO0OOooo........oooOO0OOooo........oo << 147 // extrapolate between two formula
>> 148 if(beta2 < beta2lim) {
>> 149 x = log(dedx0) + log(dedx/dedx0)*log(b2/beta2low)/log(beta2lim/beta2low);
>> 150 dedx = exp(x);
>> 151 }
>> 152 dedx0 = dedx;
>> 153 }
219 154
220 void G4mplIonisationModel::SampleSecondaries(s << 155 return dedx0;
221 const G4MaterialCutsCouple*, << 156 }
222 const G4DynamicParticle*, <<
223 G4double, <<
224 G4double) <<
225 {} <<
226 157
227 //....oooOO0OOooo........oooOO0OOooo........oo 158 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
228 159
229 G4double G4mplIonisationModel::SampleFluctuati 160 G4double G4mplIonisationModel::SampleFluctuations(
230 const G4MaterialCutsCouple* cou << 161 const G4Material* material,
231 const G4DynamicParticle* dp, 162 const G4DynamicParticle* dp,
232 const G << 163 G4double& tmax,
233 const G << 164 G4double& length,
234 const G4double length, << 165 G4double& meanLoss)
235 const G4double meanLoss) <<
236 { 166 {
237 G4double siga = Dispersion(couple->GetMateri << 167 G4double siga = Dispersion(material,dp,tmax,length);
238 G4double loss = meanLoss; 168 G4double loss = meanLoss;
239 siga = std::sqrt(siga); << 169 siga = sqrt(siga);
240 G4double twomeanLoss = meanLoss + meanLoss; 170 G4double twomeanLoss = meanLoss + meanLoss;
241 171
242 if(twomeanLoss < siga) { 172 if(twomeanLoss < siga) {
243 G4double x; 173 G4double x;
244 do { 174 do {
245 loss = twomeanLoss*G4UniformRand(); 175 loss = twomeanLoss*G4UniformRand();
246 x = (loss - meanLoss)/siga; 176 x = (loss - meanLoss)/siga;
247 // Loop checking, 07-Aug-2015, Vladimir <<
248 } while (1.0 - 0.5*x*x < G4UniformRand()); 177 } while (1.0 - 0.5*x*x < G4UniformRand());
249 } else { 178 } else {
250 do { 179 do {
251 loss = G4RandGauss::shoot(meanLoss,siga) 180 loss = G4RandGauss::shoot(meanLoss,siga);
252 // Loop checking, 07-Aug-2015, Vladimir <<
253 } while (0.0 > loss || loss > twomeanLoss) 181 } while (0.0 > loss || loss > twomeanLoss);
254 } 182 }
>> 183 //G4cout << "G4mplIonisationModel::SampleFluctuations: loss= " << loss
>> 184 //<< " siga= " << siga << G4endl;
255 return loss; 185 return loss;
256 } <<
257 <<
258 //....oooOO0OOooo........oooOO0OOooo........oo <<
259 <<
260 G4double G4mplIonisationModel::Dispersion(cons <<
261 const G4DynamicParticle* dp, <<
262 const G4double tcut, <<
263 const G4double tmax, <<
264 const G4double length) <<
265 { <<
266 G4double siga = 0.0; <<
267 G4double tau = dp->GetKineticEnergy()/mass <<
268 if(tau > 0.0) { <<
269 const G4double beta = dp->GetBeta(); <<
270 siga = (tmax/(beta*beta) - 0.5*tcut) * tw <<
271 * material->GetElectronDensity() * charg <<
272 } <<
273 return siga; <<
274 } 186 }
275 187
276 //....oooOO0OOooo........oooOO0OOooo........oo 188 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
277 189