source: trunk/source/processes/electromagnetic/polarisation/src/G4PolarizedCompton.cc@ 1199

Last change on this file since 1199 was 1196, checked in by garnier, 16 years ago

update CVS release candidate geant4.9.3.01
File size: 13.3 KB
Line 
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25//
26//
27// $Id: G4PolarizedCompton.cc,v 1.9 2008/10/30 22:34:23 schaelic Exp $
28// GEANT4 tag $Name: geant4-09-03-cand-01 $
29//
30//
31// File name: G4PolarizedCompton
32//
33// Author: Andreas Schaelicke
34// based on code by Michel Maire / Vladimir IVANTCHENKO
35// Class description
36//
37// modified version respecting media and beam polarization
38// using the stokes formalism
39//
40// Creation date: 01.05.2005
41//
42// Modifications:
43//
44// 01-01-05, include polarization description (A.Stahl)
45// 01-01-05, create asymmetry table and determine interactionlength (A.Stahl)
46// 01-05-05, update handling of media polarization (A.Schalicke)
47// 01-05-05, update polarized differential cross section (A.Schalicke)
48// 20-05-05, added polarization transfer (A.Schalicke)
49// 10-06-05, transformation between different reference frames (A.Schalicke)
50// 17-10-05, correct reference frame dependence in GetMeanFreePath (A.Schalicke)
51// 26-07-06, cross section recalculated (P.Starovoitov)
52// 09-08-06, make it work under current geant4 release (A.Schalicke)
53// 11-06-07, add PostStepGetPhysicalInteractionLength (A.Schalicke)
54// -----------------------------------------------------------------------------
55
56
57#include "G4PolarizedCompton.hh"
58#include "G4Electron.hh"
59
60#include "G4StokesVector.hh"
61#include "G4PolarizationManager.hh"
62#include "G4PolarizedComptonModel.hh"
63#include "G4ProductionCutsTable.hh"
64#include "G4PhysicsTableHelper.hh"
65#include "G4KleinNishinaCompton.hh"
66#include "G4PolarizedComptonModel.hh"
67
68//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
69
70G4PolarizedCompton::G4PolarizedCompton(const G4String& processName,
71 G4ProcessType type):
72 G4VEmProcess (processName, type),
73 buildAsymmetryTable(true),
74 useAsymmetryTable(true),
75 isInitialised(false),
76 selectedModel(0),
77 mType(10),
78 theAsymmetryTable(NULL)
79{
80 SetLambdaBinning(90);
81 SetMinKinEnergy(0.1*keV);
82 SetMaxKinEnergy(100.0*GeV);
83 SetProcessSubType(fComptonScattering);
84}
85
86//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
87
88G4PolarizedCompton::~G4PolarizedCompton()
89{
90 if (theAsymmetryTable) {
91 theAsymmetryTable->clearAndDestroy();
92 delete theAsymmetryTable;
93 }
94}
95
96//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
97
98void G4PolarizedCompton::InitialiseProcess(const G4ParticleDefinition*)
99{
100 if(!isInitialised) {
101 isInitialised = true;
102 SetBuildTableFlag(true);
103 SetSecondaryParticle(G4Electron::Electron());
104 G4double emin = MinKinEnergy();
105 G4double emax = MaxKinEnergy();
106 emModel = new G4PolarizedComptonModel();
107 if(0 == mType) selectedModel = new G4KleinNishinaCompton();
108 else if(10 == mType) selectedModel = emModel;
109 selectedModel->SetLowEnergyLimit(emin);
110 selectedModel->SetHighEnergyLimit(emax);
111 AddEmModel(1, selectedModel);
112 }
113}
114
115//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
116
117void G4PolarizedCompton::PrintInfo()
118{
119 G4cout << " Total cross sections has a good parametrisation"
120 << " from 10 KeV to (100/Z) GeV"
121 << "\n Sampling according " << selectedModel->GetName() << " model"
122 << G4endl;
123}
124
125//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
126
127void G4PolarizedCompton::SetModel(const G4String& s)
128{
129 if(s == "Klein-Nishina") mType = 0;
130 if(s == "Polarized-Compton") mType = 10;
131}
132
133
134//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
135//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
136
137
138
139G4double G4PolarizedCompton::GetMeanFreePath(
140 const G4Track& aTrack,
141 G4double previousStepSize,
142 G4ForceCondition* condition)
143{
144 // *** get unploarised mean free path from lambda table ***
145 G4double mfp = G4VEmProcess::GetMeanFreePath(aTrack, previousStepSize, condition);
146
147
148 if (theAsymmetryTable && useAsymmetryTable) {
149 // *** get asymmetry, if target is polarized ***
150 const G4DynamicParticle* aDynamicGamma = aTrack.GetDynamicParticle();
151 const G4double GammaEnergy = aDynamicGamma->GetKineticEnergy();
152 const G4StokesVector GammaPolarization = aTrack.GetPolarization();
153 const G4ParticleMomentum GammaDirection0 = aDynamicGamma->GetMomentumDirection();
154
155 G4Material* aMaterial = aTrack.GetMaterial();
156 G4VPhysicalVolume* aPVolume = aTrack.GetVolume();
157 G4LogicalVolume* aLVolume = aPVolume->GetLogicalVolume();
158
159 // G4Material* bMaterial = aLVolume->GetMaterial();
160 G4PolarizationManager * polarizationManger = G4PolarizationManager::GetInstance();
161
162 const G4bool VolumeIsPolarized = polarizationManger->IsPolarized(aLVolume);
163 G4StokesVector ElectronPolarization = polarizationManger->GetVolumePolarization(aLVolume);
164
165 if (!VolumeIsPolarized || mfp == DBL_MAX) return mfp;
166
167 if (verboseLevel>=2) {
168
169 G4cout << " Mom " << GammaDirection0 << G4endl;
170 G4cout << " Polarization " << GammaPolarization << G4endl;
171 G4cout << " MaterialPol. " << ElectronPolarization << G4endl;
172 G4cout << " Phys. Volume " << aPVolume->GetName() << G4endl;
173 G4cout << " Log. Volume " << aLVolume->GetName() << G4endl;
174 G4cout << " Material " << aMaterial << G4endl;
175 }
176
177 G4int midx= CurrentMaterialCutsCoupleIndex();
178 G4PhysicsVector * aVector=(*theAsymmetryTable)(midx);
179
180 G4double asymmetry=0;
181 if (aVector) {
182 G4bool isOutRange;
183 asymmetry = aVector->GetValue(GammaEnergy, isOutRange);
184 } else {
185 G4cout << " MaterialIndex " << midx << " is out of range \n";
186 asymmetry=0;
187 }
188
189 // we have to determine angle between particle motion
190 // and target polarisation here
191 // circ pol * Vec(ElectronPol)*Vec(PhotonMomentum)
192 // both vectors in global reference frame
193
194 G4double pol=ElectronPolarization*GammaDirection0;
195
196 G4double polProduct = GammaPolarization.p3() * pol;
197 mfp *= 1. / ( 1. + polProduct * asymmetry );
198
199 if (verboseLevel>=2) {
200 G4cout << " MeanFreePath: " << mfp / mm << " mm " << G4endl;
201 G4cout << " Asymmetry: " << asymmetry << G4endl;
202 G4cout << " PolProduct: " << polProduct << G4endl;
203 }
204 }
205
206 return mfp;
207}
208
209G4double G4PolarizedCompton::PostStepGetPhysicalInteractionLength(
210 const G4Track& aTrack,
211 G4double previousStepSize,
212 G4ForceCondition* condition)
213{
214 // *** get unploarised mean free path from lambda table ***
215 G4double mfp = G4VEmProcess::PostStepGetPhysicalInteractionLength(aTrack, previousStepSize, condition);
216
217
218 if (theAsymmetryTable && useAsymmetryTable) {
219 // *** get asymmetry, if target is polarized ***
220 const G4DynamicParticle* aDynamicGamma = aTrack.GetDynamicParticle();
221 const G4double GammaEnergy = aDynamicGamma->GetKineticEnergy();
222 const G4StokesVector GammaPolarization = aTrack.GetPolarization();
223 const G4ParticleMomentum GammaDirection0 = aDynamicGamma->GetMomentumDirection();
224
225 G4Material* aMaterial = aTrack.GetMaterial();
226 G4VPhysicalVolume* aPVolume = aTrack.GetVolume();
227 G4LogicalVolume* aLVolume = aPVolume->GetLogicalVolume();
228
229 // G4Material* bMaterial = aLVolume->GetMaterial();
230 G4PolarizationManager * polarizationManger = G4PolarizationManager::GetInstance();
231
232 const G4bool VolumeIsPolarized = polarizationManger->IsPolarized(aLVolume);
233 G4StokesVector ElectronPolarization = polarizationManger->GetVolumePolarization(aLVolume);
234
235 if (!VolumeIsPolarized || mfp == DBL_MAX) return mfp;
236
237 if (verboseLevel>=2) {
238
239 G4cout << " Mom " << GammaDirection0 << G4endl;
240 G4cout << " Polarization " << GammaPolarization << G4endl;
241 G4cout << " MaterialPol. " << ElectronPolarization << G4endl;
242 G4cout << " Phys. Volume " << aPVolume->GetName() << G4endl;
243 G4cout << " Log. Volume " << aLVolume->GetName() << G4endl;
244 G4cout << " Material " << aMaterial << G4endl;
245 }
246
247 G4int midx= CurrentMaterialCutsCoupleIndex();
248 G4PhysicsVector * aVector=(*theAsymmetryTable)(midx);
249
250 G4double asymmetry=0;
251 if (aVector) {
252 G4bool isOutRange;
253 asymmetry = aVector->GetValue(GammaEnergy, isOutRange);
254 } else {
255 G4cout << " MaterialIndex " << midx << " is out of range \n";
256 asymmetry=0;
257 }
258
259 // we have to determine angle between particle motion
260 // and target polarisation here
261 // circ pol * Vec(ElectronPol)*Vec(PhotonMomentum)
262 // both vectors in global reference frame
263
264 G4double pol=ElectronPolarization*GammaDirection0;
265
266 G4double polProduct = GammaPolarization.p3() * pol;
267 mfp *= 1. / ( 1. + polProduct * asymmetry );
268
269 if (verboseLevel>=2) {
270 G4cout << " MeanFreePath: " << mfp / mm << " mm " << G4endl;
271 G4cout << " Asymmetry: " << asymmetry << G4endl;
272 G4cout << " PolProduct: " << polProduct << G4endl;
273 }
274 }
275
276 return mfp;
277}
278
279//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
280
281void G4PolarizedCompton::PreparePhysicsTable(const G4ParticleDefinition& part)
282{
283 G4VEmProcess::PreparePhysicsTable(part);
284 if(buildAsymmetryTable)
285 theAsymmetryTable = G4PhysicsTableHelper::PreparePhysicsTable(theAsymmetryTable);
286}
287
288//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
289
290
291void G4PolarizedCompton::BuildPhysicsTable(const G4ParticleDefinition& part)
292{
293 // *** build (unpolarized) cross section tables (Lambda)
294 G4VEmProcess::BuildPhysicsTable(part);
295 if(buildAsymmetryTable)
296 BuildAsymmetryTable(part);
297}
298
299//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
300
301
302void G4PolarizedCompton::BuildAsymmetryTable(const G4ParticleDefinition& part)
303{
304 // Access to materials
305 const G4ProductionCutsTable* theCoupleTable=
306 G4ProductionCutsTable::GetProductionCutsTable();
307 size_t numOfCouples = theCoupleTable->GetTableSize();
308 for(size_t i=0; i<numOfCouples; ++i) {
309 if (!theAsymmetryTable) break;
310 if (theAsymmetryTable->GetFlag(i)) {
311
312 // create physics vector and fill it
313 const G4MaterialCutsCouple* couple = theCoupleTable->GetMaterialCutsCouple(i);
314 // use same parameters as for lambda
315 G4PhysicsVector* aVector = LambdaPhysicsVector(couple);
316 // modelManager->FillLambdaVector(aVector, couple, startFromNull);
317
318 for (G4int j = 0 ; j < LambdaBinning() ; ++j ) {
319 G4double lowEdgeEnergy = aVector->GetLowEdgeEnergy(j);
320 G4double tasm=0.;
321 G4double asym = ComputeAsymmetry(lowEdgeEnergy, couple, part, 0., tasm);
322 aVector->PutValue(j,asym);
323 }
324
325 G4PhysicsTableHelper::SetPhysicsVector(theAsymmetryTable, i, aVector);
326 }
327 }
328
329}
330
331//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
332
333
334G4double G4PolarizedCompton::ComputeAsymmetry(G4double energy,
335 const G4MaterialCutsCouple* couple,
336 const G4ParticleDefinition& aParticle,
337 G4double cut,
338 G4double & tAsymmetry)
339{
340 G4double lAsymmetry = 0.0;
341 tAsymmetry=0;
342
343 //
344 // calculate polarized cross section
345 //
346 G4ThreeVector thePolarization=G4ThreeVector(0.,0.,1.);
347 emModel->SetTargetPolarization(thePolarization);
348 emModel->SetBeamPolarization(thePolarization);
349 G4double sigma2=emModel->CrossSection(couple,&aParticle,energy,cut,energy);
350
351 //
352 // calculate unpolarized cross section
353 //
354 thePolarization=G4ThreeVector();
355 emModel->SetTargetPolarization(thePolarization);
356 emModel->SetBeamPolarization(thePolarization);
357 G4double sigma0=emModel->CrossSection(couple,&aParticle,energy,cut,energy);
358
359 // determine assymmetries
360 if (sigma0>0.) {
361 lAsymmetry=sigma2/sigma0-1.;
362 }
363 return lAsymmetry;
364}
365
366//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
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