| 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,v 1.36 2010-10-26 13:52:32 vnivanch Exp $
>> 27 // GEANT4 tag $Name: geant4-09-04-patch-02 $
26 // 28 //
27 // ------------------------------------------- 29 // -------------------------------------------------------------------
28 // 30 //
29 // GEANT4 Class file 31 // GEANT4 Class file
30 // 32 //
31 // 33 //
32 // File name: G4MuBremsstrahlungModel 34 // File name: G4MuBremsstrahlungModel
33 // 35 //
34 // Author: Vladimir Ivanchenko on base 36 // Author: Vladimir Ivanchenko on base of Laszlo Urban code
35 // 37 //
36 // Creation date: 24.06.2002 38 // Creation date: 24.06.2002
37 // 39 //
38 // Modifications: 40 // Modifications:
39 // 41 //
40 // 04-12-02 Change G4DynamicParticle construct 42 // 04-12-02 Change G4DynamicParticle constructor in PostStepDoIt (V.Ivanchenko)
41 // 23-12-02 Change interface in order to move 43 // 23-12-02 Change interface in order to move to cut per region (V.Ivanchenko)
42 // 24-01-03 Fix for compounds (V.Ivanchenko) 44 // 24-01-03 Fix for compounds (V.Ivanchenko)
43 // 27-01-03 Make models region aware (V.Ivanch 45 // 27-01-03 Make models region aware (V.Ivanchenko)
44 // 13-02-03 Add name (V.Ivanchenko) 46 // 13-02-03 Add name (V.Ivanchenko)
45 // 10-02-04 Add lowestKinEnergy (V.Ivanchenko) 47 // 10-02-04 Add lowestKinEnergy (V.Ivanchenko)
46 // 08-04-05 Major optimisation of internal int 48 // 08-04-05 Major optimisation of internal interfaces (V.Ivanchenko)
47 // 03-08-05 Angular correlations according to 49 // 03-08-05 Angular correlations according to PRM (V.Ivanchenko)
48 // 13-02-06 add ComputeCrossSectionPerAtom (mm 50 // 13-02-06 add ComputeCrossSectionPerAtom (mma)
49 // 21-03-06 Fix problem of initialisation in c 51 // 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 52 // 07-11-07 Improve sampling of final state (A.Bogdanov)
51 // 28-02-08 Use precomputed Z^1/3 and Log(A) ( 53 // 28-02-08 Use precomputed Z^1/3 and Log(A) (V.Ivanchenko)
52 // 31-05-13 Use element selectors instead of l << 54 //
>> 55
>> 56 //
>> 57 // Class Description:
>> 58 //
53 // 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" <<
61 #include "G4SystemOfUnits.hh" <<
62 #include "G4Gamma.hh" 66 #include "G4Gamma.hh"
63 #include "G4MuonMinus.hh" 67 #include "G4MuonMinus.hh"
64 #include "G4MuonPlus.hh" 68 #include "G4MuonPlus.hh"
65 #include "Randomize.hh" 69 #include "Randomize.hh"
66 #include "G4Material.hh" 70 #include "G4Material.hh"
67 #include "G4Element.hh" 71 #include "G4Element.hh"
68 #include "G4ElementVector.hh" 72 #include "G4ElementVector.hh"
69 #include "G4ProductionCutsTable.hh" 73 #include "G4ProductionCutsTable.hh"
70 #include "G4ModifiedMephi.hh" <<
71 #include "G4ParticleChangeForLoss.hh" 74 #include "G4ParticleChangeForLoss.hh"
72 #include "G4Log.hh" <<
73 75
74 //....oooOO0OOooo........oooOO0OOooo........oo 76 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
75 //....oooOO0OOooo........oooOO0OOooo........oo 77 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
76 78
77 const G4double G4MuBremsstrahlungModel::xgi[] << 79 using namespace std;
78 {0.03377,0.16940,0.38069,0.61931,0.83060,0.9 <<
79 const G4double G4MuBremsstrahlungModel::wgi[] <<
80 {0.08566,0.18038,0.23396,0.23396,0.18038,0.0 <<
81 G4double G4MuBremsstrahlungModel::fDN[] = {0.0 <<
82 80
83 G4MuBremsstrahlungModel::G4MuBremsstrahlungMod 81 G4MuBremsstrahlungModel::G4MuBremsstrahlungModel(const G4ParticleDefinition* p,
84 82 const G4String& nam)
85 : G4VEmModel(nam), 83 : G4VEmModel(nam),
86 sqrte(std::sqrt(G4Exp(1.))), << 84 particle(0),
87 lowestKinEnergy(0.1*CLHEP::GeV), << 85 sqrte(sqrt(exp(1.))),
88 minThreshold(0.9*CLHEP::keV) << 86 bh(202.4),
>> 87 bh1(446.),
>> 88 btf(183.),
>> 89 btf1(1429.),
>> 90 fParticleChange(0),
>> 91 lowestKinEnergy(1.0*GeV),
>> 92 minThreshold(1.0*keV)
89 { 93 {
90 theGamma = G4Gamma::Gamma(); 94 theGamma = G4Gamma::Gamma();
91 nist = G4NistManager::Instance(); << 95 nist = G4NistManager::Instance();
92 96
93 SetAngularDistribution(new G4ModifiedMephi() << 97 mass = rmass = cc = coeff = 1.0;
94 98
95 if (nullptr != p) { SetParticle(p); } << 99 if(p) { SetParticle(p); }
96 if (0.0 == fDN[1]) { <<
97 for (G4int i=1; i<93; ++i) { <<
98 G4double dn = 1.54*nist->GetA27(i); <<
99 fDN[i] = dn; <<
100 if(1 < i) { <<
101 fDN[i] /= std::pow(dn, 1./G4double(i)); <<
102 } <<
103 } <<
104 } <<
105 } 100 }
106 101
107 //....oooOO0OOooo........oooOO0OOooo........oo 102 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
108 103
109 G4double G4MuBremsstrahlungModel::MinEnergyCut << 104 G4MuBremsstrahlungModel::~G4MuBremsstrahlungModel()
110 <<
111 { 105 {
112 return minThreshold; << 106 size_t n = partialSumSigma.size();
113 } << 107 if(n > 0) {
114 << 108 for(size_t i=0; i<n; i++) {
115 //....oooOO0OOooo........oooOO0OOooo........oo << 109 delete partialSumSigma[i];
116 << 110 }
117 G4double G4MuBremsstrahlungModel::MinPrimaryEn << 111 }
118 <<
119 <<
120 { <<
121 return std::max(lowestKinEnergy, cut); <<
122 } 112 }
123 113
124 //....oooOO0OOooo........oooOO0OOooo........oo 114 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
125 115
126 void G4MuBremsstrahlungModel::SetParticle(cons << 116 G4double G4MuBremsstrahlungModel::MinEnergyCut(const G4ParticleDefinition*,
>> 117 const G4MaterialCutsCouple*)
127 { 118 {
128 if(nullptr == particle) { << 119 return minThreshold;
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 } 120 }
136 121
137 //....oooOO0OOooo........oooOO0OOooo........oo 122 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
138 123
139 void G4MuBremsstrahlungModel::Initialise(const 124 void G4MuBremsstrahlungModel::Initialise(const G4ParticleDefinition* p,
140 const 125 const G4DataVector& cuts)
141 { 126 {
142 SetParticle(p); << 127 if(p) { SetParticle(p); }
143 if(nullptr == fParticleChange) { <<
144 fParticleChange = GetParticleChangeForLoss <<
145 } <<
146 if(IsMaster() && p == particle && lowestKinE <<
147 InitialiseElementSelectors(p, cuts); <<
148 } <<
149 } <<
150 128
151 //....oooOO0OOooo........oooOO0OOooo........oo << 129 // partial cross section is computed for fixed energy
>> 130 G4double fixedEnergy = 0.5*HighEnergyLimit();
152 131
153 void G4MuBremsstrahlungModel::InitialiseLocal( << 132 const G4ProductionCutsTable* theCoupleTable=
154 << 133 G4ProductionCutsTable::GetProductionCutsTable();
155 { << 134 if(theCoupleTable) {
156 if(p == particle && lowestKinEnergy < HighEn << 135 G4int numOfCouples = theCoupleTable->GetTableSize();
157 SetElementSelectors(masterModel->GetElemen << 136
>> 137 // clear old data
>> 138 G4int nn = partialSumSigma.size();
>> 139 G4int nc = cuts.size();
>> 140 if(nn > 0) {
>> 141 for (G4int ii=0; ii<nn; ii++){
>> 142 G4DataVector* a = partialSumSigma[ii];
>> 143 if ( a ) { delete a; }
>> 144 }
>> 145 partialSumSigma.clear();
>> 146 }
>> 147 // fill new data
>> 148 if (numOfCouples>0) {
>> 149 for (G4int i=0; i<numOfCouples; i++) {
>> 150 G4double cute = DBL_MAX;
>> 151
>> 152 // protection for usage with extrapolator
>> 153 if(i < nc) { cute = cuts[i]; }
>> 154
>> 155 const G4MaterialCutsCouple* couple =
>> 156 theCoupleTable->GetMaterialCutsCouple(i);
>> 157 const G4Material* material = couple->GetMaterial();
>> 158 G4DataVector* dv = ComputePartialSumSigma(material,fixedEnergy,cute);
>> 159 partialSumSigma.push_back(dv);
>> 160 }
>> 161 }
158 } 162 }
>> 163
>> 164 // define pointer to G4ParticleChange
>> 165 if(!fParticleChange) { fParticleChange = GetParticleChangeForLoss(); }
159 } 166 }
160 167
161 //....oooOO0OOooo........oooOO0OOooo........oo 168 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
162 169
163 G4double G4MuBremsstrahlungModel::ComputeDEDXP 170 G4double G4MuBremsstrahlungModel::ComputeDEDXPerVolume(
164 << 171 const G4Material* material,
165 172 const G4ParticleDefinition*,
166 173 G4double kineticEnergy,
167 174 G4double cutEnergy)
168 { 175 {
169 G4double dedx = 0.0; 176 G4double dedx = 0.0;
170 if (kineticEnergy <= lowestKinEnergy) { retu << 177 if (kineticEnergy <= lowestKinEnergy) return dedx;
171 178
172 G4double cut = std::max(cutEnergy, minThresh << 179 G4double tmax = kineticEnergy;
173 cut = std::min(cut, kineticEnergy); << 180 G4double cut = std::min(cutEnergy,tmax);
>> 181 if(cut < minThreshold) cut = minThreshold;
174 182
175 const G4ElementVector* theElementVector = ma 183 const G4ElementVector* theElementVector = material->GetElementVector();
176 const G4double* theAtomicNumDensityVector = 184 const G4double* theAtomicNumDensityVector =
177 material->GetAtomicNumDensityVector(); 185 material->GetAtomicNumDensityVector();
178 186
179 // loop for elements in the material 187 // loop for elements in the material
180 for (size_t i=0; i<material->GetNumberOfElem << 188 for (size_t i=0; i<material->GetNumberOfElements(); i++) {
>> 189
181 G4double loss = 190 G4double loss =
182 ComputMuBremLoss((*theElementVector)[i]- 191 ComputMuBremLoss((*theElementVector)[i]->GetZ(), kineticEnergy, cut);
>> 192
183 dedx += loss*theAtomicNumDensityVector[i]; 193 dedx += loss*theAtomicNumDensityVector[i];
184 } 194 }
185 // G4cout << "BR e= " << kineticEnergy << " 195 // G4cout << "BR e= " << kineticEnergy << " dedx= " << dedx << G4endl;
186 dedx = std::max(dedx, 0.); << 196 if(dedx < 0.) dedx = 0.;
187 return dedx; 197 return dedx;
188 } 198 }
189 199
190 //....oooOO0OOooo........oooOO0OOooo........oo 200 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
191 201
192 G4double G4MuBremsstrahlungModel::ComputMuBrem 202 G4double G4MuBremsstrahlungModel::ComputMuBremLoss(G4double Z,
193 203 G4double tkin, G4double cut)
194 { 204 {
195 G4double totalEnergy = mass + tkin; 205 G4double totalEnergy = mass + tkin;
196 static const G4double ak1 = 0.05; << 206 G4double ak1 = 0.05;
197 static const G4int k2 = 5; << 207 G4int k2=5;
>> 208 G4double xgi[]={0.03377,0.16940,0.38069,0.61931,0.83060,0.96623};
>> 209 G4double wgi[]={0.08566,0.18038,0.23396,0.23396,0.18038,0.08566};
198 G4double loss = 0.; 210 G4double loss = 0.;
199 211
200 G4double vcut = cut/totalEnergy; 212 G4double vcut = cut/totalEnergy;
201 G4int kkk = (G4int)(vcut/ak1) + k2; << 213 G4double vmax = tkin/totalEnergy;
202 if (kkk > 8) { kkk = 8; } << 214
203 else if (kkk < 1) { kkk = 1; } << 215 G4double aaa = 0.;
204 G4double hhh = vcut/(G4double)(kkk); << 216 G4double bbb = vcut;
205 << 217 if(vcut>vmax) bbb=vmax ;
206 G4double aa = 0.; << 218 G4int kkk = (G4int)((bbb-aaa)/ak1)+k2 ;
207 for(G4int l=0; l<kkk; ++l) { << 219 G4double hhh=(bbb-aaa)/float(kkk) ;
208 for(G4int i=0; i<6; ++i) { << 220
>> 221 G4double aa = aaa;
>> 222 for(G4int l=0; l<kkk; l++)
>> 223 {
>> 224 for(G4int i=0; i<6; i++)
>> 225 {
209 G4double ep = (aa + xgi[i]*hhh)*totalEne 226 G4double ep = (aa + xgi[i]*hhh)*totalEnergy;
210 loss += ep*wgi[i]*ComputeDMicroscopicCro 227 loss += ep*wgi[i]*ComputeDMicroscopicCrossSection(tkin, Z, ep);
211 } 228 }
212 aa += hhh; 229 aa += hhh;
213 } 230 }
214 231
215 loss *= hhh*totalEnergy; << 232 loss *=hhh*totalEnergy ;
>> 233
216 return loss; 234 return loss;
217 } 235 }
218 236
219 //....oooOO0OOooo........oooOO0OOooo........oo 237 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
220 238
221 G4double G4MuBremsstrahlungModel::ComputeMicro 239 G4double G4MuBremsstrahlungModel::ComputeMicroscopicCrossSection(
222 G4d 240 G4double tkin,
223 G4d 241 G4double Z,
224 G4d 242 G4double cut)
225 { 243 {
226 G4double totalEnergy = tkin + mass; 244 G4double totalEnergy = tkin + mass;
227 static const G4double ak1 = 2.3; << 245 G4double ak1 = 2.3;
228 static const G4int k2 = 4; << 246 G4int k2 = 4;
>> 247 G4double xgi[]={0.03377,0.16940,0.38069,0.61931,0.83060,0.96623};
>> 248 G4double wgi[]={0.08566,0.18038,0.23396,0.23396,0.18038,0.08566};
229 G4double cross = 0.; 249 G4double cross = 0.;
230 250
231 if(cut >= tkin) return cross; 251 if(cut >= tkin) return cross;
232 252
233 G4double vcut = cut/totalEnergy; 253 G4double vcut = cut/totalEnergy;
234 G4double vmax = tkin/totalEnergy; 254 G4double vmax = tkin/totalEnergy;
235 255
236 G4double aaa = G4Log(vcut); << 256 G4double aaa = log(vcut);
237 G4double bbb = G4Log(vmax); << 257 G4double bbb = log(vmax);
238 G4int kkk = (G4int)((bbb-aaa)/ak1) + k2 ; << 258 G4int kkk = (G4int)((bbb-aaa)/ak1)+k2 ;
239 if(kkk > 8) { kkk = 8; } << 259 G4double hhh = (bbb-aaa)/G4double(kkk);
240 else if (kkk < 1) { kkk = 1; } << 260
241 G4double hhh = (bbb-aaa)/(G4double)(kkk); <<
242 G4double aa = aaa; 261 G4double aa = aaa;
243 262
244 for(G4int l=0; l<kkk; ++l) { << 263 for(G4int l=0; l<kkk; l++)
245 for(G4int i=0; i<6; ++i) { << 264 {
246 G4double ep = G4Exp(aa + xgi[i]*hhh)*tot << 265 for(G4int i=0; i<6; i++)
>> 266 {
>> 267 G4double ep = exp(aa + xgi[i]*hhh)*totalEnergy;
247 cross += ep*wgi[i]*ComputeDMicroscopicCr 268 cross += ep*wgi[i]*ComputeDMicroscopicCrossSection(tkin, Z, ep);
248 } 269 }
249 aa += hhh; 270 aa += hhh;
250 } 271 }
251 272
252 cross *= hhh; << 273 cross *=hhh;
>> 274
253 //G4cout << "BR e= " << tkin<< " cross= " < 275 //G4cout << "BR e= " << tkin<< " cross= " << cross/barn << G4endl;
>> 276
254 return cross; 277 return cross;
255 } 278 }
256 279
257 //....oooOO0OOooo........oooOO0OOooo........oo 280 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
258 281
259 G4double G4MuBremsstrahlungModel::ComputeDMicr 282 G4double G4MuBremsstrahlungModel::ComputeDMicroscopicCrossSection(
260 G4d 283 G4double tkin,
261 G4d 284 G4double Z,
262 G4d 285 G4double gammaEnergy)
263 // differential cross section 286 // differential cross section
264 { 287 {
265 G4double dxsection = 0.; 288 G4double dxsection = 0.;
266 if(gammaEnergy > tkin) { return dxsection; } << 289
>> 290 if( gammaEnergy > tkin) return dxsection ;
267 291
268 G4double E = tkin + mass ; 292 G4double E = tkin + mass ;
269 G4double v = gammaEnergy/E ; 293 G4double v = gammaEnergy/E ;
270 G4double delta = 0.5*mass*mass*v/(E-gammaEne 294 G4double delta = 0.5*mass*mass*v/(E-gammaEnergy) ;
271 G4double rab0 = delta*sqrte ; << 295 G4double rab0=delta*sqrte ;
272 296
273 G4int iz = G4lrint(Z); << 297 G4int iz = G4int(Z);
274 if(iz < 1) { iz = 1; } << 298 if(iz < 1) iz = 1;
275 else if(iz > 92) { iz = 92; } <<
276 299
277 G4double z13 = 1.0/nist->GetZ13(iz); 300 G4double z13 = 1.0/nist->GetZ13(iz);
278 G4double dnstar = fDN[iz]; << 301 G4double dn = 1.54*nist->GetA27(iz);
279 302
280 G4double b,b1; << 303 G4double b,b1,dnstar ;
281 if(1 == iz) { << 304
>> 305 if(1 == iz)
>> 306 {
282 b = bh; 307 b = bh;
283 b1 = bh1; 308 b1 = bh1;
284 } else { << 309 dnstar = dn;
>> 310 }
>> 311 else
>> 312 {
285 b = btf; 313 b = btf;
286 b1 = btf1; 314 b1 = btf1;
>> 315 dnstar = dn/std::pow(dn, 1./Z);
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=log(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=log(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
>> 364 G4DataVector* G4MuBremsstrahlungModel::ComputePartialSumSigma(
>> 365 const G4Material* material,
>> 366 G4double kineticEnergy,
>> 367 G4double cut)
>> 368
>> 369 // Build the table of cross section per element.
>> 370 // The table is built for material
>> 371 // This table is used to select randomly an element in the material.
>> 372 {
>> 373 G4int nElements = material->GetNumberOfElements();
>> 374 const G4ElementVector* theElementVector = material->GetElementVector();
>> 375 const G4double* theAtomNumDensityVector =
>> 376 material->GetAtomicNumDensityVector();
>> 377
>> 378 G4DataVector* dv = new G4DataVector();
>> 379
>> 380 G4double cross = 0.0;
>> 381
>> 382 for (G4int i=0; i<nElements; i++ ) {
>> 383 cross += theAtomNumDensityVector[i]
>> 384 * ComputeMicroscopicCrossSection(kineticEnergy,
>> 385 (*theElementVector)[i]->GetZ(), cut);
>> 386 dv->push_back(cross);
>> 387 }
>> 388 return dv;
>> 389 }
>> 390
>> 391 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
>> 392
334 void G4MuBremsstrahlungModel::SampleSecondarie 393 void G4MuBremsstrahlungModel::SampleSecondaries(
335 std::vector<G4Dy 394 std::vector<G4DynamicParticle*>* vdp,
336 const G4Material << 395 const G4MaterialCutsCouple* couple,
337 const G4DynamicP << 396 const G4DynamicParticle* dp,
338 G4double minEner << 397 G4double minEnergy,
339 G4double maxEner << 398 G4double maxEnergy)
340 { 399 {
341 G4double kineticEnergy = dp->GetKineticEnerg 400 G4double kineticEnergy = dp->GetKineticEnergy();
342 // check against insufficient energy 401 // check against insufficient energy
343 G4double tmax = std::min(kineticEnergy, maxE 402 G4double tmax = std::min(kineticEnergy, maxEnergy);
344 G4double tmin = std::min(kineticEnergy, minE 403 G4double tmin = std::min(kineticEnergy, minEnergy);
345 tmin = std::max(tmin, minThreshold); << 404 if(tmin < minThreshold) tmin = minThreshold;
346 if(tmin >= tmax) return; 405 if(tmin >= tmax) return;
347 406
348 // ===== sampling of energy transfer ====== 407 // ===== sampling of energy transfer ======
349 408
350 G4ParticleMomentum partDirection = dp->GetMo 409 G4ParticleMomentum partDirection = dp->GetMomentumDirection();
351 410
352 // select randomly one element constituing t 411 // select randomly one element constituing the material
353 const G4Element* anElement = SelectRandomAto << 412 const G4Element* anElement = SelectRandomAtom(couple);
354 G4double Z = anElement->GetZ(); 413 G4double Z = anElement->GetZ();
>> 414
>> 415 G4double totalEnergy = kineticEnergy + mass;
>> 416 G4double totalMomentum = sqrt(kineticEnergy*(kineticEnergy + 2.0*mass));
>> 417
355 G4double func1 = tmin* 418 G4double func1 = tmin*
356 ComputeDMicroscopicCrossSection(kineticEne << 419 ComputeDMicroscopicCrossSection(kineticEnergy,Z,tmin);
357 420
358 G4double gEnergy; << 421 G4double lnepksi, epksi;
359 G4double func2; 422 G4double func2;
360 423
361 G4double xmin = G4Log(tmin/minThreshold); <<
362 G4double xmax = G4Log(tmax/tmin); <<
363 <<
364 do { 424 do {
365 gEnergy = minThreshold*G4Exp(xmin + G4Unif << 425 lnepksi = log(tmin) + G4UniformRand()*log(kineticEnergy/tmin);
366 func2 = gEnergy*ComputeDMicroscopicCrossSe << 426 epksi = exp(lnepksi);
367 << 427 func2 = epksi*ComputeDMicroscopicCrossSection(kineticEnergy,Z,epksi);
368 // Loop checking, 03-Aug-2015, Vladimir Iv << 428
369 } while(func2 < func1*G4UniformRand()); 429 } while(func2 < func1*G4UniformRand());
370 430
371 // angles of the emitted gamma using general << 431 G4double gEnergy = epksi;
372 G4ThreeVector gamDir = << 432
373 GetAngularDistribution()->SampleDirection( << 433 // ===== sample angle =====
374 << 434
375 // create G4DynamicParticle object for the G << 435 G4double gam = totalEnergy/mass;
376 G4DynamicParticle* gamma = new G4DynamicPart << 436 G4double rmax = gam*std::min(1.0, totalEnergy/gEnergy - 1.0);
377 vdp->push_back(gamma); << 437 G4double rmax2= rmax*rmax;
378 << 438 G4double x = G4UniformRand()*rmax2/(1.0 + rmax2);
379 // compute post-interaction kinematics of pr << 439
380 // energy-momentum conservation << 440 G4double theta = sqrt(x/(1.0 - x))/gam;
381 const G4double totMomentum = << 441 G4double sint = sin(theta);
382 std::sqrt(kineticEnergy*(kineticEnergy + 2 << 442 G4double phi = twopi * G4UniformRand() ;
383 G4ThreeVector dir = << 443 G4double dirx = sint*cos(phi), diry = sint*sin(phi), dirz = cos(theta) ;
384 (totMomentum*dp->GetMomentumDirection() - << 444
385 const G4double finalE = kineticEnergy - gEne << 445 G4ThreeVector gDirection(dirx, diry, dirz);
386 << 446 gDirection.rotateUz(partDirection);
387 // if secondary gamma energy is higher than << 447
388 // then stop tracking the primary particle a << 448 partDirection *= totalMomentum;
389 // instead of the primary one << 449 partDirection -= gEnergy*gDirection;
390 if (gEnergy > SecondaryThreshold()) { << 450 partDirection = partDirection.unit();
391 fParticleChange->ProposeTrackStatus(fStopA << 451
392 fParticleChange->SetProposedKineticEnergy( << 452 // primary change
393 G4DynamicParticle* newdp = new G4DynamicPa << 453 kineticEnergy -= gEnergy;
394 vdp->push_back(newdp); << 454 fParticleChange->SetProposedKineticEnergy(kineticEnergy);
395 } else { << 455 fParticleChange->SetProposedMomentumDirection(partDirection);
396 // continue tracking the primary e-/e+ oth << 456
397 fParticleChange->SetProposedMomentumDirect << 457 // save secondary
398 fParticleChange->SetProposedKineticEnergy( << 458 G4DynamicParticle* aGamma =
>> 459 new G4DynamicParticle(theGamma,gDirection,gEnergy);
>> 460 vdp->push_back(aGamma);
>> 461 }
>> 462
>> 463 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
>> 464
>> 465 const G4Element* G4MuBremsstrahlungModel::SelectRandomAtom(
>> 466 const G4MaterialCutsCouple* couple) const
>> 467 {
>> 468 // select randomly 1 element within the material
>> 469
>> 470 const G4Material* material = couple->GetMaterial();
>> 471 G4int nElements = material->GetNumberOfElements();
>> 472 const G4ElementVector* theElementVector = material->GetElementVector();
>> 473 if(1 == nElements) { return (*theElementVector)[0]; }
>> 474 else if(1 > nElements) { return 0; }
>> 475
>> 476 G4DataVector* dv = partialSumSigma[couple->GetIndex()];
>> 477 G4double rval = G4UniformRand()*((*dv)[nElements-1]);
>> 478 for (G4int i=0; i<nElements; i++) {
>> 479 if (rval <= (*dv)[i]) { return (*theElementVector)[i]; }
399 } 480 }
>> 481 return (*theElementVector)[nElements-1];
400 } 482 }
401 483
402 //....oooOO0OOooo........oooOO0OOooo........oo 484 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
403 485