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28 //
29 // GEANT4 Class file
30 //
31 //
32 // File name: G4LivermoreBremsstrahlungModel
33 //
34 // Author: Vladimir Ivanchenko use inheritance from Andreas Schaelicke
35 // base class implementing ultra relativistic bremsstrahlung
36 // model
37 //
38 // Creation date: 04.10.2011
39 //
40 // Modifications:
41 //
42 // -------------------------------------------------------------------
43 //
44 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
45 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
46
47 #include "G4LivermoreBremsstrahlungModel.hh"
48 #include "G4PhysicalConstants.hh"
49 #include "G4SystemOfUnits.hh"
50 #include "G4Electron.hh"
51 #include "G4Positron.hh"
52 #include "G4Gamma.hh"
53 #include "Randomize.hh"
54 #include "G4AutoLock.hh"
55 #include "G4Material.hh"
56 #include "G4Element.hh"
57 #include "G4ElementVector.hh"
58 #include "G4ProductionCutsTable.hh"
59 #include "G4ParticleChangeForLoss.hh"
60 #include "G4Generator2BS.hh"
61
62 #include "G4Physics2DVector.hh"
63 #include "G4Exp.hh"
64 #include "G4Log.hh"
65
66 #include "G4ios.hh"
67 #include <fstream>
68 #include <iomanip>
69
70 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
71
72 namespace { G4Mutex LivermoreBremsstrahlungModelMutex = G4MUTEX_INITIALIZER; }
73 using namespace std;
74
75
76 G4Physics2DVector* G4LivermoreBremsstrahlungModel::dataSB[] = {nullptr};
77 G4double G4LivermoreBremsstrahlungModel::ylimit[] = {0.0};
78 G4double G4LivermoreBremsstrahlungModel::expnumlim = -12.;
79
80 static const G4double emaxlog = 4*G4Log(10.);
81 static const G4double alpha = CLHEP::twopi*CLHEP::fine_structure_const;
82 static const G4double epeaklimit= 300*CLHEP::MeV;
83 static const G4double elowlimit = 20*CLHEP::keV;
84
85 G4LivermoreBremsstrahlungModel::G4LivermoreBremsstrahlungModel(
86 const G4ParticleDefinition* p, const G4String& nam)
87 : G4eBremsstrahlungRelModel(p,nam),useBicubicInterpolation(false)
88 {
89 SetLowEnergyLimit(10.0*eV);
90 SetAngularDistribution(new G4Generator2BS());
91 }
92
93 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
94
95 G4LivermoreBremsstrahlungModel::~G4LivermoreBremsstrahlungModel()
96 {
97 if(IsMaster()) {
98 for(size_t i=0; i<101; ++i) {
99 if(dataSB[i]) {
100 delete dataSB[i];
101 dataSB[i] = nullptr;
102 }
103 }
104 }
105 }
106
107 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
108
109 void G4LivermoreBremsstrahlungModel::Initialise(const G4ParticleDefinition* p,
110 const G4DataVector& cuts)
111 {
112 // Access to elements
113 if(IsMaster()) {
114 // check environment variable
115 // Build the complete string identifying the file with the data set
116 const char* path = G4FindDataDir("G4LEDATA");
117
118 const G4ElementTable* theElmTable = G4Element::GetElementTable();
119 size_t numOfElm = G4Element::GetNumberOfElements();
120 if(numOfElm > 0) {
121 for(size_t i=0; i<numOfElm; ++i) {
122 G4int Z = (*theElmTable)[i]->GetZasInt();
123 if(Z < 1) { Z = 1; }
124 else if(Z > 100) { Z = 100; }
125 //G4cout << "Z= " << Z << G4endl;
126 // Initialisation
127 if(!dataSB[Z]) { ReadData(Z, path); }
128 }
129 }
130 }
131 G4eBremsstrahlungRelModel::Initialise(p, cuts);
132 }
133
134 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
135
136 G4String G4LivermoreBremsstrahlungModel::DirectoryPath() const
137 {
138 return "/livermore/brem/br";
139 }
140
141 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
142
143 void G4LivermoreBremsstrahlungModel::ReadData(G4int Z, const char* path)
144 {
145 if(dataSB[Z]) { return; }
146 const char* datadir = path;
147
148 if(nullptr == datadir) {
149 datadir = G4FindDataDir("G4LEDATA");
150 if(!datadir) {
151 G4Exception("G4LivermoreBremsstrahlungModel::ReadData()","em0006",
152 FatalException,"Environment variable G4LEDATA not defined");
153 return;
154 }
155 }
156 std::ostringstream ost;
157 ost << datadir << DirectoryPath() << Z;
158 std::ifstream fin(ost.str().c_str());
159 if( !fin.is_open()) {
160 G4ExceptionDescription ed;
161 ed << "Bremsstrahlung data file <" << ost.str().c_str()
162 << "> is not opened!";
163 G4Exception("G4LivermoreBremsstrahlungModel::ReadData()","em0003",
164 FatalException,ed,
165 "G4LEDATA version should be G4EMLOW8.0 or later.");
166 return;
167 }
168 //G4cout << "G4LivermoreBremsstrahlungModel read from <" << ost.str().c_str()
169 // << ">" << G4endl;
170 G4Physics2DVector* v = new G4Physics2DVector();
171 if(v->Retrieve(fin)) {
172 if(useBicubicInterpolation) { v->SetBicubicInterpolation(true); }
173 dataSB[Z] = v;
174 ylimit[Z] = v->Value(0.97, emaxlog, idx, idy);
175 } else {
176 G4ExceptionDescription ed;
177 ed << "Bremsstrahlung data file <" << ost.str().c_str()
178 << "> is not retrieved!";
179 G4Exception("G4LivermoreBremsstrahlungModel::ReadData()","em0005",
180 FatalException,ed,
181 "G4LEDATA version should be G4EMLOW8.0 or later.");
182 delete v;
183 }
184 }
185
186 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
187
188 G4double
189 G4LivermoreBremsstrahlungModel::ComputeDXSectionPerAtom(G4double gammaEnergy)
190 {
191 if(gammaEnergy < 0.0 || fPrimaryKinEnergy <= 0.0) { return 0.0; }
192 G4double x = gammaEnergy/fPrimaryKinEnergy;
193 G4double y = G4Log(fPrimaryKinEnergy/MeV);
194 G4int Z = fCurrentIZ;
195
196 //G4cout << "G4LivermoreBremsstrahlungModel::ComputeDXSectionPerAtom Z= " << Z
197 // << " x= " << x << " y= " << y << " " << dataSB[Z] << G4endl;
198 if(!dataSB[Z]) { InitialiseForElement(0, Z); }
199
200 G4double invb2 = fPrimaryTotalEnergy*fPrimaryTotalEnergy/(fPrimaryKinEnergy
201 *(fPrimaryKinEnergy + 2.*fPrimaryParticleMass));
202 G4double cross = dataSB[Z]->Value(x,y,idx,idy)*invb2*millibarn/gBremFactor;
203
204 if(!fIsElectron) {
205 G4double invbeta1 = sqrt(invb2);
206 G4double e2 = fPrimaryKinEnergy - gammaEnergy;
207 if(e2 > 0.0) {
208 G4double invbeta2 = (e2 + fPrimaryParticleMass)
209 /sqrt(e2*(e2 + 2.*fPrimaryParticleMass));
210 G4double xxx = alpha*fCurrentIZ*(invbeta1 - invbeta2);
211 if(xxx < expnumlim) { cross = 0.0; }
212 else { cross *= G4Exp(xxx); }
213 } else {
214 cross = 0.0;
215 }
216 }
217
218 return cross;
219 }
220
221 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
222
223 void
224 G4LivermoreBremsstrahlungModel::SampleSecondaries(
225 std::vector<G4DynamicParticle*>* vdp,
226 const G4MaterialCutsCouple* couple,
227 const G4DynamicParticle* dp,
228 G4double cutEnergy,
229 G4double maxEnergy)
230 {
231 G4double kineticEnergy = dp->GetKineticEnergy();
232 G4double cut = std::min(cutEnergy, kineticEnergy);
233 G4double emax = std::min(maxEnergy, kineticEnergy);
234 if(cut >= emax) { return; }
235 // sets total energy, kinetic energy and density correction
236 SetupForMaterial(fPrimaryParticle, couple->GetMaterial(), kineticEnergy);
237
238 const G4Element* elm =
239 SelectRandomAtom(couple,fPrimaryParticle,kineticEnergy,cut,emax);
240 fCurrentIZ = elm->GetZasInt();
241 G4int Z = fCurrentIZ;
242
243 G4double totMomentum = sqrt(kineticEnergy*(fPrimaryTotalEnergy+electron_mass_c2));
244 /*
245 G4cout << "G4LivermoreBremsstrahlungModel::SampleSecondaries E(MeV)= "
246 << kineticEnergy/MeV
247 << " Z= " << Z << " cut(MeV)= " << cut/MeV
248 << " emax(MeV)= " << emax/MeV << " corr= " << fDensityCorr << G4endl;
249 */
250 G4double xmin = G4Log(cut*cut + fDensityCorr);
251 G4double xmax = G4Log(emax*emax + fDensityCorr);
252 G4double y = G4Log(kineticEnergy/MeV);
253
254 G4double gammaEnergy, v;
255
256 // majoranta
257 G4double x0 = cut/kineticEnergy;
258 G4double vmax = dataSB[Z]->Value(x0, y, idx, idy)*1.02;
259
260 // majoranta corrected for e-
261 if(fIsElectron && x0 < 0.97 &&
262 ((kineticEnergy > epeaklimit) || (kineticEnergy < elowlimit))) {
263 G4double ylim = std::min(ylimit[Z],1.1*dataSB[Z]->Value(0.97,y,idx,idy));
264 if(ylim > vmax) { vmax = ylim; }
265 }
266 if(x0 < 0.05) { vmax *= 1.2; }
267
268 do {
269 //++ncount;
270 G4double x = G4Exp(xmin + G4UniformRand()*(xmax - xmin)) - fDensityCorr;
271 if(x < 0.0) { x = 0.0; }
272 gammaEnergy = sqrt(x);
273 G4double x1 = gammaEnergy/kineticEnergy;
274 v = dataSB[Z]->Value(x1, y, idx, idy);
275
276 // correction for positrons
277 if(!fIsElectron) {
278 G4double e1 = kineticEnergy - cut;
279 G4double invbeta1 = (e1 + fPrimaryParticleMass)
280 /sqrt(e1*(e1 + 2*fPrimaryParticleMass));
281 G4double e2 = kineticEnergy - gammaEnergy;
282 G4double invbeta2 = (e2 + fPrimaryParticleMass)
283 /sqrt(e2*(e2 + 2*fPrimaryParticleMass));
284 G4double xxx = twopi*fine_structure_const*fCurrentIZ*(invbeta1 - invbeta2);
285
286 if(xxx < expnumlim) { v = 0.0; }
287 else { v *= G4Exp(xxx); }
288 }
289
290 if (v > 1.05*vmax && nwarn < 5) {
291 ++nwarn;
292 G4ExceptionDescription ed;
293 ed << "### G4LivermoreBremsstrahlungModel Warning: Majoranta exceeded! "
294 << v << " > " << vmax << " by " << v/vmax
295 << " Egamma(MeV)= " << gammaEnergy
296 << " Ee(MeV)= " << kineticEnergy
297 << " Z= " << Z << " " << fPrimaryParticle->GetParticleName();
298
299 if ( 20 == nwarn ) {
300 ed << "\n ### G4LivermoreBremsstrahlungModel Warnings stopped";
301 }
302 G4Exception("G4LivermoreBremsstrahlungModel::SampleScattering","em0044",
303 JustWarning, ed,"");
304
305 }
306 } while (v < vmax*G4UniformRand());
307
308 //
309 // angles of the emitted gamma. ( Z - axis along the parent particle)
310 // use general interface
311 //
312
313 G4ThreeVector gammaDirection =
314 GetAngularDistribution()->SampleDirection(dp,fPrimaryTotalEnergy-gammaEnergy,
315 Z, couple->GetMaterial());
316
317 // create G4DynamicParticle object for the Gamma
318 G4DynamicParticle* gamma =
319 new G4DynamicParticle(fGammaParticle,gammaDirection,gammaEnergy);
320 vdp->push_back(gamma);
321
322 G4ThreeVector direction = (totMomentum*dp->GetMomentumDirection()
323 - gammaEnergy*gammaDirection).unit();
324
325 /*
326 G4cout << "### G4SBModel: v= "
327 << " Eg(MeV)= " << gammaEnergy
328 << " Ee(MeV)= " << kineticEnergy
329 << " DirE " << direction << " DirG " << gammaDirection
330 << G4endl;
331 */
332 // energy of primary
333 G4double finalE = kineticEnergy - gammaEnergy;
334
335 // stop tracking and create new secondary instead of primary
336 if(gammaEnergy > SecondaryThreshold()) {
337 fParticleChange->ProposeTrackStatus(fStopAndKill);
338 fParticleChange->SetProposedKineticEnergy(0.0);
339 G4DynamicParticle* el =
340 new G4DynamicParticle(const_cast<G4ParticleDefinition*>(fPrimaryParticle),
341 direction, finalE);
342 vdp->push_back(el);
343
344 // continue tracking
345 } else {
346 fParticleChange->SetProposedMomentumDirection(direction);
347 fParticleChange->SetProposedKineticEnergy(finalE);
348 }
349 }
350
351 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
352
353 void G4LivermoreBremsstrahlungModel::InitialiseForElement(
354 const G4ParticleDefinition*,
355 G4int Z)
356 {
357 G4AutoLock l(&LivermoreBremsstrahlungModelMutex);
358 if(!dataSB[Z]) { ReadData(Z); }
359 l.unlock();
360 }
361
362 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
363