| 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: G4MuBremsstrahlungModel.cc 85023 2014-10-23 09:56:39Z gcosmo $
26 // 27 //
27 // ------------------------------------------- 28 // -------------------------------------------------------------------
28 // 29 //
29 // GEANT4 Class file 30 // GEANT4 Class file
30 // 31 //
31 // 32 //
32 // File name: G4MuBremsstrahlungModel 33 // File name: G4MuBremsstrahlungModel
33 // 34 //
34 // Author: Vladimir Ivanchenko on base 35 // Author: Vladimir Ivanchenko on base of Laszlo Urban code
35 // 36 //
36 // Creation date: 24.06.2002 37 // Creation date: 24.06.2002
37 // 38 //
38 // Modifications: 39 // Modifications:
39 // 40 //
40 // 04-12-02 Change G4DynamicParticle construct 41 // 04-12-02 Change G4DynamicParticle constructor in PostStepDoIt (V.Ivanchenko)
41 // 23-12-02 Change interface in order to move 42 // 23-12-02 Change interface in order to move to cut per region (V.Ivanchenko)
42 // 24-01-03 Fix for compounds (V.Ivanchenko) 43 // 24-01-03 Fix for compounds (V.Ivanchenko)
43 // 27-01-03 Make models region aware (V.Ivanch 44 // 27-01-03 Make models region aware (V.Ivanchenko)
44 // 13-02-03 Add name (V.Ivanchenko) 45 // 13-02-03 Add name (V.Ivanchenko)
45 // 10-02-04 Add lowestKinEnergy (V.Ivanchenko) 46 // 10-02-04 Add lowestKinEnergy (V.Ivanchenko)
46 // 08-04-05 Major optimisation of internal int 47 // 08-04-05 Major optimisation of internal interfaces (V.Ivanchenko)
47 // 03-08-05 Angular correlations according to 48 // 03-08-05 Angular correlations according to PRM (V.Ivanchenko)
48 // 13-02-06 add ComputeCrossSectionPerAtom (mm 49 // 13-02-06 add ComputeCrossSectionPerAtom (mma)
49 // 21-03-06 Fix problem of initialisation in c 50 // 21-03-06 Fix problem of initialisation in case when cuts are not defined (VI)
50 // 07-11-07 Improve sampling of final state (A 51 // 07-11-07 Improve sampling of final state (A.Bogdanov)
51 // 28-02-08 Use precomputed Z^1/3 and Log(A) ( 52 // 28-02-08 Use precomputed Z^1/3 and Log(A) (V.Ivanchenko)
52 // 31-05-13 Use element selectors instead of l 53 // 31-05-13 Use element selectors instead of local data structure (V.Ivanchenko)
53 // 54 //
>> 55
>> 56 //
>> 57 // Class Description:
>> 58 //
>> 59 //
54 // ------------------------------------------- 60 // -------------------------------------------------------------------
55 // 61 //
56 //....oooOO0OOooo........oooOO0OOooo........oo 62 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
57 //....oooOO0OOooo........oooOO0OOooo........oo 63 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
58 64
59 #include "G4MuBremsstrahlungModel.hh" 65 #include "G4MuBremsstrahlungModel.hh"
60 #include "G4PhysicalConstants.hh" 66 #include "G4PhysicalConstants.hh"
61 #include "G4SystemOfUnits.hh" 67 #include "G4SystemOfUnits.hh"
62 #include "G4Gamma.hh" 68 #include "G4Gamma.hh"
63 #include "G4MuonMinus.hh" 69 #include "G4MuonMinus.hh"
64 #include "G4MuonPlus.hh" 70 #include "G4MuonPlus.hh"
65 #include "Randomize.hh" 71 #include "Randomize.hh"
66 #include "G4Material.hh" 72 #include "G4Material.hh"
67 #include "G4Element.hh" 73 #include "G4Element.hh"
68 #include "G4ElementVector.hh" 74 #include "G4ElementVector.hh"
69 #include "G4ProductionCutsTable.hh" 75 #include "G4ProductionCutsTable.hh"
70 #include "G4ModifiedMephi.hh" <<
71 #include "G4ParticleChangeForLoss.hh" 76 #include "G4ParticleChangeForLoss.hh"
>> 77 //#include "G4LossTableManager.hh"
72 #include "G4Log.hh" 78 #include "G4Log.hh"
>> 79 #include "G4Exp.hh"
73 80
74 //....oooOO0OOooo........oooOO0OOooo........oo 81 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
75 //....oooOO0OOooo........oooOO0OOooo........oo 82 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
76 83
>> 84 using namespace std;
>> 85
77 const G4double G4MuBremsstrahlungModel::xgi[] 86 const G4double G4MuBremsstrahlungModel::xgi[] =
78 {0.03377,0.16940,0.38069,0.61931,0.83060,0.9 87 {0.03377,0.16940,0.38069,0.61931,0.83060,0.96623};
79 const G4double G4MuBremsstrahlungModel::wgi[] 88 const G4double G4MuBremsstrahlungModel::wgi[] =
80 {0.08566,0.18038,0.23396,0.23396,0.18038,0.0 89 {0.08566,0.18038,0.23396,0.23396,0.18038,0.08566};
81 G4double G4MuBremsstrahlungModel::fDN[] = {0.0 90 G4double G4MuBremsstrahlungModel::fDN[] = {0.0};
82 91
83 G4MuBremsstrahlungModel::G4MuBremsstrahlungMod 92 G4MuBremsstrahlungModel::G4MuBremsstrahlungModel(const G4ParticleDefinition* p,
84 93 const G4String& nam)
85 : G4VEmModel(nam), 94 : G4VEmModel(nam),
86 sqrte(std::sqrt(G4Exp(1.))), << 95 particle(0),
87 lowestKinEnergy(0.1*CLHEP::GeV), << 96 sqrte(sqrt(G4Exp(1.))),
88 minThreshold(0.9*CLHEP::keV) << 97 bh(202.4),
>> 98 bh1(446.),
>> 99 btf(183.),
>> 100 btf1(1429.),
>> 101 fParticleChange(0),
>> 102 lowestKinEnergy(1.0*GeV),
>> 103 minThreshold(0.9*keV)
89 { 104 {
90 theGamma = G4Gamma::Gamma(); 105 theGamma = G4Gamma::Gamma();
91 nist = G4NistManager::Instance(); << 106 nist = G4NistManager::Instance();
>> 107
>> 108 lowestKinEnergy = 1.*GeV;
92 109
93 SetAngularDistribution(new G4ModifiedMephi() << 110 mass = rmass = cc = coeff = 1.0;
94 111
95 if (nullptr != p) { SetParticle(p); } << 112 if(0.0 == fDN[1]) {
96 if (0.0 == fDN[1]) { << 113 for(G4int i=1; i<93; ++i) {
97 for (G4int i=1; i<93; ++i) { <<
98 G4double dn = 1.54*nist->GetA27(i); 114 G4double dn = 1.54*nist->GetA27(i);
99 fDN[i] = dn; 115 fDN[i] = dn;
100 if(1 < i) { 116 if(1 < i) {
101 fDN[i] /= std::pow(dn, 1./G4double(i)); 117 fDN[i] /= std::pow(dn, 1./G4double(i));
102 } 118 }
103 } 119 }
104 } 120 }
>> 121
>> 122 if(p) { SetParticle(p); }
105 } 123 }
106 124
107 //....oooOO0OOooo........oooOO0OOooo........oo 125 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
108 126
109 G4double G4MuBremsstrahlungModel::MinEnergyCut << 127 G4MuBremsstrahlungModel::~G4MuBremsstrahlungModel()
110 << 128 {}
111 { <<
112 return minThreshold; <<
113 } <<
114 129
115 //....oooOO0OOooo........oooOO0OOooo........oo 130 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
116 131
117 G4double G4MuBremsstrahlungModel::MinPrimaryEn << 132 G4double G4MuBremsstrahlungModel::MinEnergyCut(const G4ParticleDefinition*,
118 << 133 const G4MaterialCutsCouple*)
119 <<
120 { 134 {
121 return std::max(lowestKinEnergy, cut); << 135 return minThreshold;
122 } 136 }
123 137
124 //....oooOO0OOooo........oooOO0OOooo........oo 138 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
125 139
126 void G4MuBremsstrahlungModel::SetParticle(cons << 140 G4double G4MuBremsstrahlungModel::MinPrimaryEnergy(const G4Material*,
>> 141 const G4ParticleDefinition*,
>> 142 G4double cut)
127 { 143 {
128 if(nullptr == particle) { << 144 return std::max(lowestKinEnergy,cut);
129 particle = p; <<
130 mass = particle->GetPDGMass(); <<
131 rmass = mass/CLHEP::electron_mass_c2 ; <<
132 cc = CLHEP::classic_electr_radius/rmass ; <<
133 coeff = 16.*CLHEP::fine_structure_const*cc <<
134 } <<
135 } 145 }
136 146
137 //....oooOO0OOooo........oooOO0OOooo........oo 147 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
138 148
139 void G4MuBremsstrahlungModel::Initialise(const 149 void G4MuBremsstrahlungModel::Initialise(const G4ParticleDefinition* p,
140 const 150 const G4DataVector& cuts)
141 { 151 {
142 SetParticle(p); << 152 if(p) { SetParticle(p); }
143 if(nullptr == fParticleChange) { << 153
144 fParticleChange = GetParticleChangeForLoss << 154 // define pointer to G4ParticleChange
145 } << 155 if(!fParticleChange) { fParticleChange = GetParticleChangeForLoss(); }
>> 156
146 if(IsMaster() && p == particle && lowestKinE 157 if(IsMaster() && p == particle && lowestKinEnergy < HighEnergyLimit()) {
147 InitialiseElementSelectors(p, cuts); 158 InitialiseElementSelectors(p, cuts);
148 } 159 }
149 } 160 }
150 161
151 //....oooOO0OOooo........oooOO0OOooo........oo 162 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
152 163
153 void G4MuBremsstrahlungModel::InitialiseLocal( 164 void G4MuBremsstrahlungModel::InitialiseLocal(const G4ParticleDefinition* p,
154 << 165 G4VEmModel* masterModel)
155 { 166 {
156 if(p == particle && lowestKinEnergy < HighEn 167 if(p == particle && lowestKinEnergy < HighEnergyLimit()) {
157 SetElementSelectors(masterModel->GetElemen 168 SetElementSelectors(masterModel->GetElementSelectors());
158 } 169 }
159 } 170 }
160 171
161 //....oooOO0OOooo........oooOO0OOooo........oo 172 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
162 173
163 G4double G4MuBremsstrahlungModel::ComputeDEDXP 174 G4double G4MuBremsstrahlungModel::ComputeDEDXPerVolume(
164 << 175 const G4Material* material,
165 176 const G4ParticleDefinition*,
166 177 G4double kineticEnergy,
167 178 G4double cutEnergy)
168 { 179 {
169 G4double dedx = 0.0; 180 G4double dedx = 0.0;
170 if (kineticEnergy <= lowestKinEnergy) { retu 181 if (kineticEnergy <= lowestKinEnergy) { return dedx; }
171 182
172 G4double cut = std::max(cutEnergy, minThresh << 183 G4double tmax = kineticEnergy;
173 cut = std::min(cut, kineticEnergy); << 184 G4double cut = std::min(cutEnergy,tmax);
>> 185 if(cut < minThreshold) { cut = minThreshold; }
174 186
175 const G4ElementVector* theElementVector = ma 187 const G4ElementVector* theElementVector = material->GetElementVector();
176 const G4double* theAtomicNumDensityVector = 188 const G4double* theAtomicNumDensityVector =
177 material->GetAtomicNumDensityVector(); 189 material->GetAtomicNumDensityVector();
178 190
179 // loop for elements in the material 191 // loop for elements in the material
180 for (size_t i=0; i<material->GetNumberOfElem << 192 for (size_t i=0; i<material->GetNumberOfElements(); i++) {
>> 193
181 G4double loss = 194 G4double loss =
182 ComputMuBremLoss((*theElementVector)[i]- 195 ComputMuBremLoss((*theElementVector)[i]->GetZ(), kineticEnergy, cut);
>> 196
183 dedx += loss*theAtomicNumDensityVector[i]; 197 dedx += loss*theAtomicNumDensityVector[i];
184 } 198 }
185 // G4cout << "BR e= " << kineticEnergy << " 199 // G4cout << "BR e= " << kineticEnergy << " dedx= " << dedx << G4endl;
186 dedx = std::max(dedx, 0.); << 200 if(dedx < 0.) dedx = 0.;
187 return dedx; 201 return dedx;
188 } 202 }
189 203
190 //....oooOO0OOooo........oooOO0OOooo........oo 204 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
191 205
192 G4double G4MuBremsstrahlungModel::ComputMuBrem 206 G4double G4MuBremsstrahlungModel::ComputMuBremLoss(G4double Z,
193 207 G4double tkin, G4double cut)
194 { 208 {
195 G4double totalEnergy = mass + tkin; 209 G4double totalEnergy = mass + tkin;
196 static const G4double ak1 = 0.05; 210 static const G4double ak1 = 0.05;
197 static const G4int k2 = 5; << 211 static const G4int k2=5;
198 G4double loss = 0.; 212 G4double loss = 0.;
199 213
200 G4double vcut = cut/totalEnergy; 214 G4double vcut = cut/totalEnergy;
201 G4int kkk = (G4int)(vcut/ak1) + k2; << 215 G4double vmax = tkin/totalEnergy;
202 if (kkk > 8) { kkk = 8; } << 216
203 else if (kkk < 1) { kkk = 1; } << 217 G4double aaa = 0.;
204 G4double hhh = vcut/(G4double)(kkk); << 218 G4double bbb = vcut;
205 << 219 if(vcut>vmax) { bbb = vmax; }
206 G4double aa = 0.; << 220 G4int kkk = (G4int)((bbb-aaa)/ak1)+k2;
207 for(G4int l=0; l<kkk; ++l) { << 221 if(kkk < 1) { kkk = 1; }
208 for(G4int i=0; i<6; ++i) { << 222
>> 223 G4double hhh=(bbb-aaa)/G4double(kkk);
>> 224
>> 225 G4double aa = aaa;
>> 226 for(G4int l=0; l<kkk; l++)
>> 227 {
>> 228 for(G4int i=0; i<6; i++)
>> 229 {
209 G4double ep = (aa + xgi[i]*hhh)*totalEne 230 G4double ep = (aa + xgi[i]*hhh)*totalEnergy;
210 loss += ep*wgi[i]*ComputeDMicroscopicCro 231 loss += ep*wgi[i]*ComputeDMicroscopicCrossSection(tkin, Z, ep);
211 } 232 }
212 aa += hhh; 233 aa += hhh;
213 } 234 }
214 235
215 loss *= hhh*totalEnergy; << 236 loss *=hhh*totalEnergy ;
>> 237
216 return loss; 238 return loss;
217 } 239 }
218 240
219 //....oooOO0OOooo........oooOO0OOooo........oo 241 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
220 242
221 G4double G4MuBremsstrahlungModel::ComputeMicro 243 G4double G4MuBremsstrahlungModel::ComputeMicroscopicCrossSection(
222 G4d 244 G4double tkin,
223 G4d 245 G4double Z,
224 G4d 246 G4double cut)
225 { 247 {
226 G4double totalEnergy = tkin + mass; 248 G4double totalEnergy = tkin + mass;
227 static const G4double ak1 = 2.3; 249 static const G4double ak1 = 2.3;
228 static const G4int k2 = 4; << 250 static const G4int k2 = 4;
229 G4double cross = 0.; 251 G4double cross = 0.;
230 252
231 if(cut >= tkin) return cross; 253 if(cut >= tkin) return cross;
232 254
233 G4double vcut = cut/totalEnergy; 255 G4double vcut = cut/totalEnergy;
234 G4double vmax = tkin/totalEnergy; 256 G4double vmax = tkin/totalEnergy;
235 257
236 G4double aaa = G4Log(vcut); 258 G4double aaa = G4Log(vcut);
237 G4double bbb = G4Log(vmax); 259 G4double bbb = G4Log(vmax);
238 G4int kkk = (G4int)((bbb-aaa)/ak1) + k2 ; << 260 G4int kkk = (G4int)((bbb-aaa)/ak1)+k2 ;
239 if(kkk > 8) { kkk = 8; } << 261 if(kkk < 1) { kkk = 1; }
240 else if (kkk < 1) { kkk = 1; } << 262
241 G4double hhh = (bbb-aaa)/(G4double)(kkk); << 263 G4double hhh = (bbb-aaa)/G4double(kkk);
>> 264
242 G4double aa = aaa; 265 G4double aa = aaa;
243 266
244 for(G4int l=0; l<kkk; ++l) { << 267 for(G4int l=0; l<kkk; l++)
245 for(G4int i=0; i<6; ++i) { << 268 {
>> 269 for(G4int i=0; i<6; i++)
>> 270 {
246 G4double ep = G4Exp(aa + xgi[i]*hhh)*tot 271 G4double ep = G4Exp(aa + xgi[i]*hhh)*totalEnergy;
247 cross += ep*wgi[i]*ComputeDMicroscopicCr 272 cross += ep*wgi[i]*ComputeDMicroscopicCrossSection(tkin, Z, ep);
248 } 273 }
249 aa += hhh; 274 aa += hhh;
250 } 275 }
251 276
252 cross *= hhh; << 277 cross *=hhh;
>> 278
253 //G4cout << "BR e= " << tkin<< " cross= " < 279 //G4cout << "BR e= " << tkin<< " cross= " << cross/barn << G4endl;
>> 280
254 return cross; 281 return cross;
255 } 282 }
256 283
257 //....oooOO0OOooo........oooOO0OOooo........oo 284 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
258 285
259 G4double G4MuBremsstrahlungModel::ComputeDMicr 286 G4double G4MuBremsstrahlungModel::ComputeDMicroscopicCrossSection(
260 G4d 287 G4double tkin,
261 G4d 288 G4double Z,
262 G4d 289 G4double gammaEnergy)
263 // differential cross section 290 // differential cross section
264 { 291 {
265 G4double dxsection = 0.; 292 G4double dxsection = 0.;
>> 293
266 if(gammaEnergy > tkin) { return dxsection; } 294 if(gammaEnergy > tkin) { return dxsection; }
267 295
268 G4double E = tkin + mass ; 296 G4double E = tkin + mass ;
269 G4double v = gammaEnergy/E ; 297 G4double v = gammaEnergy/E ;
270 G4double delta = 0.5*mass*mass*v/(E-gammaEne 298 G4double delta = 0.5*mass*mass*v/(E-gammaEnergy) ;
271 G4double rab0 = delta*sqrte ; 299 G4double rab0 = delta*sqrte ;
272 300
273 G4int iz = G4lrint(Z); 301 G4int iz = G4lrint(Z);
274 if(iz < 1) { iz = 1; } 302 if(iz < 1) { iz = 1; }
275 else if(iz > 92) { iz = 92; } 303 else if(iz > 92) { iz = 92; }
276 304
277 G4double z13 = 1.0/nist->GetZ13(iz); 305 G4double z13 = 1.0/nist->GetZ13(iz);
278 G4double dnstar = fDN[iz]; 306 G4double dnstar = fDN[iz];
279 307
280 G4double b,b1; 308 G4double b,b1;
>> 309
281 if(1 == iz) { 310 if(1 == iz) {
282 b = bh; 311 b = bh;
283 b1 = bh1; 312 b1 = bh1;
284 } else { 313 } else {
285 b = btf; 314 b = btf;
286 b1 = btf1; 315 b1 = btf1;
287 } 316 }
288 317
289 // nucleus contribution logarithm 318 // nucleus contribution logarithm
290 G4double rab1 = b*z13; << 319 G4double rab1=b*z13;
291 G4double fn = G4Log(rab1/(dnstar*(CLHEP::ele << 320 G4double fn=G4Log(rab1/(dnstar*(electron_mass_c2+rab0*rab1))*
292 (mass + delta*(dnstar*sqrte-2.))); << 321 (mass+delta*(dnstar*sqrte-2.))) ;
293 fn = std::max(fn, 0.); << 322 if(fn <0.) { fn = 0.; }
294 // electron contribution logarithm 323 // electron contribution logarithm
295 G4double epmax1 = E/(1.+0.5*mass*rmass/E); << 324 G4double epmax1=E/(1.+0.5*mass*rmass/E) ;
296 G4double fe = 0.; << 325 G4double fe=0.;
297 if(gammaEnergy < epmax1) { << 326 if(gammaEnergy<epmax1)
298 G4double rab2 = b1*z13*z13; << 327 {
299 fe = G4Log(rab2*mass/((1.+delta*rmass/(CLH << 328 G4double rab2=b1*z13*z13 ;
300 (CLHEP::electron_mass_c2+rab0*rab2))); << 329 fe=G4Log(rab2*mass/((1.+delta*rmass/(electron_mass_c2*sqrte))*
301 fe = std::max(fe, 0.); << 330 (electron_mass_c2+rab0*rab2))) ;
>> 331 if(fe<0.) { fe=0.; }
302 } 332 }
303 333
304 dxsection = coeff*(1.-v*(1. - 0.75*v))*Z*(fn 334 dxsection = coeff*(1.-v*(1. - 0.75*v))*Z*(fn*Z + fe)/gammaEnergy;
305 dxsection = std::max(dxsection, 0.0); << 335
306 return dxsection; 336 return dxsection;
307 } 337 }
308 338
309 //....oooOO0OOooo........oooOO0OOooo........oo 339 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
310 340
311 G4double G4MuBremsstrahlungModel::ComputeCross 341 G4double G4MuBremsstrahlungModel::ComputeCrossSectionPerAtom(
312 con 342 const G4ParticleDefinition*,
313 343 G4double kineticEnergy,
314 << 344 G4double Z, G4double,
315 345 G4double cutEnergy,
316 346 G4double maxEnergy)
317 { 347 {
318 G4double cross = 0.0; 348 G4double cross = 0.0;
319 if (kineticEnergy <= lowestKinEnergy) return 349 if (kineticEnergy <= lowestKinEnergy) return cross;
320 G4double tmax = std::min(maxEnergy, kineticE 350 G4double tmax = std::min(maxEnergy, kineticEnergy);
321 G4double cut = std::min(cutEnergy, kineticE 351 G4double cut = std::min(cutEnergy, kineticEnergy);
322 if (cut < minThreshold) cut = minThreshold; << 352 if(cut < minThreshold) cut = minThreshold;
323 if (cut >= tmax) return cross; 353 if (cut >= tmax) return cross;
324 354
325 cross = ComputeMicroscopicCrossSection (kine 355 cross = ComputeMicroscopicCrossSection (kineticEnergy, Z, cut);
326 if(tmax < kineticEnergy) { 356 if(tmax < kineticEnergy) {
327 cross -= ComputeMicroscopicCrossSection(ki 357 cross -= ComputeMicroscopicCrossSection(kineticEnergy, Z, tmax);
328 } 358 }
329 return cross; 359 return cross;
330 } 360 }
331 361
332 //....oooOO0OOooo........oooOO0OOooo........oo 362 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
333 363
334 void G4MuBremsstrahlungModel::SampleSecondarie 364 void G4MuBremsstrahlungModel::SampleSecondaries(
335 std::vector<G4Dy 365 std::vector<G4DynamicParticle*>* vdp,
336 const G4Material << 366 const G4MaterialCutsCouple* couple,
337 const G4DynamicP << 367 const G4DynamicParticle* dp,
338 G4double minEner << 368 G4double minEnergy,
339 G4double maxEner << 369 G4double maxEnergy)
340 { 370 {
341 G4double kineticEnergy = dp->GetKineticEnerg 371 G4double kineticEnergy = dp->GetKineticEnergy();
342 // check against insufficient energy 372 // check against insufficient energy
343 G4double tmax = std::min(kineticEnergy, maxE 373 G4double tmax = std::min(kineticEnergy, maxEnergy);
344 G4double tmin = std::min(kineticEnergy, minE 374 G4double tmin = std::min(kineticEnergy, minEnergy);
345 tmin = std::max(tmin, minThreshold); << 375 if(tmin < minThreshold) tmin = minThreshold;
346 if(tmin >= tmax) return; 376 if(tmin >= tmax) return;
347 377
348 // ===== sampling of energy transfer ====== 378 // ===== sampling of energy transfer ======
349 379
350 G4ParticleMomentum partDirection = dp->GetMo 380 G4ParticleMomentum partDirection = dp->GetMomentumDirection();
351 381
352 // select randomly one element constituing t 382 // select randomly one element constituing the material
353 const G4Element* anElement = SelectRandomAto 383 const G4Element* anElement = SelectRandomAtom(couple,particle,kineticEnergy);
354 G4double Z = anElement->GetZ(); 384 G4double Z = anElement->GetZ();
>> 385
>> 386 G4double totalEnergy = kineticEnergy + mass;
>> 387 G4double totalMomentum = sqrt(kineticEnergy*(kineticEnergy + 2.0*mass));
>> 388
355 G4double func1 = tmin* 389 G4double func1 = tmin*
356 ComputeDMicroscopicCrossSection(kineticEne << 390 ComputeDMicroscopicCrossSection(kineticEnergy,Z,tmin);
357 391
358 G4double gEnergy; << 392 G4double lnepksi, epksi;
359 G4double func2; 393 G4double func2;
360 394
361 G4double xmin = G4Log(tmin/minThreshold); << 395 G4double xmin = G4Log(tmin/MeV);
362 G4double xmax = G4Log(tmax/tmin); << 396 G4double xmax = G4Log(kineticEnergy/tmin);
363 397
364 do { 398 do {
365 gEnergy = minThreshold*G4Exp(xmin + G4Unif << 399 lnepksi = xmin + G4UniformRand()*xmax;
366 func2 = gEnergy*ComputeDMicroscopicCrossSe << 400 epksi = MeV*G4Exp(lnepksi);
367 << 401 func2 = epksi*ComputeDMicroscopicCrossSection(kineticEnergy,Z,epksi);
368 // Loop checking, 03-Aug-2015, Vladimir Iv << 402
369 } while(func2 < func1*G4UniformRand()); 403 } while(func2 < func1*G4UniformRand());
370 404
371 // angles of the emitted gamma using general << 405 G4double gEnergy = epksi;
372 G4ThreeVector gamDir = << 406
373 GetAngularDistribution()->SampleDirection( << 407 // ===== sample angle =====
374 << 408
375 // create G4DynamicParticle object for the G << 409 G4double gam = totalEnergy/mass;
376 G4DynamicParticle* gamma = new G4DynamicPart << 410 G4double rmax = gam*std::min(1.0, totalEnergy/gEnergy - 1.0);
377 vdp->push_back(gamma); << 411 G4double rmax2= rmax*rmax;
378 << 412 G4double x = G4UniformRand()*rmax2/(1.0 + rmax2);
379 // compute post-interaction kinematics of pr << 413
380 // energy-momentum conservation << 414 G4double theta = sqrt(x/(1.0 - x))/gam;
381 const G4double totMomentum = << 415 G4double sint = sin(theta);
382 std::sqrt(kineticEnergy*(kineticEnergy + 2 << 416 G4double phi = twopi * G4UniformRand() ;
383 G4ThreeVector dir = << 417 G4double dirx = sint*cos(phi), diry = sint*sin(phi), dirz = cos(theta) ;
384 (totMomentum*dp->GetMomentumDirection() - << 418
385 const G4double finalE = kineticEnergy - gEne << 419 G4ThreeVector gDirection(dirx, diry, dirz);
386 << 420 gDirection.rotateUz(partDirection);
387 // if secondary gamma energy is higher than << 421
388 // then stop tracking the primary particle a << 422 partDirection *= totalMomentum;
389 // instead of the primary one << 423 partDirection -= gEnergy*gDirection;
390 if (gEnergy > SecondaryThreshold()) { << 424 partDirection = partDirection.unit();
391 fParticleChange->ProposeTrackStatus(fStopA << 425
392 fParticleChange->SetProposedKineticEnergy( << 426 // primary change
393 G4DynamicParticle* newdp = new G4DynamicPa << 427 kineticEnergy -= gEnergy;
394 vdp->push_back(newdp); << 428 fParticleChange->SetProposedKineticEnergy(kineticEnergy);
395 } else { << 429 fParticleChange->SetProposedMomentumDirection(partDirection);
396 // continue tracking the primary e-/e+ oth << 430
397 fParticleChange->SetProposedMomentumDirect << 431 // save secondary
398 fParticleChange->SetProposedKineticEnergy( << 432 G4DynamicParticle* aGamma =
399 } << 433 new G4DynamicParticle(theGamma,gDirection,gEnergy);
>> 434 vdp->push_back(aGamma);
400 } 435 }
401 436
402 //....oooOO0OOooo........oooOO0OOooo........oo 437 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
403 438