1 | // |
---|
2 | // ******************************************************************** |
---|
3 | // * License and Disclaimer * |
---|
4 | // * * |
---|
5 | // * The Geant4 software is copyright of the Copyright Holders of * |
---|
6 | // * the Geant4 Collaboration. It is provided under the terms and * |
---|
7 | // * conditions of the Geant4 Software License, included in the file * |
---|
8 | // * LICENSE and available at http://cern.ch/geant4/license . These * |
---|
9 | // * include a list of copyright holders. * |
---|
10 | // * * |
---|
11 | // * Neither the authors of this software system, nor their employing * |
---|
12 | // * institutes,nor the agencies providing financial support for this * |
---|
13 | // * work make any representation or warranty, express or implied, * |
---|
14 | // * regarding this software system or assume any liability for its * |
---|
15 | // * use. Please see the license in the file LICENSE and URL above * |
---|
16 | // * for the full disclaimer and the limitation of liability. * |
---|
17 | // * * |
---|
18 | // * This code implementation is the result of the scientific and * |
---|
19 | // * technical work of the GEANT4 collaboration. * |
---|
20 | // * By using, copying, modifying or distributing the software (or * |
---|
21 | // * any work based on the software) you agree to acknowledge its * |
---|
22 | // * use in resulting scientific publications, and indicate your * |
---|
23 | // * acceptance of all terms of the Geant4 Software license. * |
---|
24 | // ******************************************************************** |
---|
25 | // |
---|
26 | // $Id: G4AdjointIonIonisationModel.cc,v 1.2 2009/11/20 10:31:20 ldesorgh Exp $ |
---|
27 | // GEANT4 tag $Name: geant4-09-03 $ |
---|
28 | // |
---|
29 | #include "G4AdjointIonIonisationModel.hh" |
---|
30 | #include "G4AdjointCSManager.hh" |
---|
31 | |
---|
32 | |
---|
33 | #include "G4Integrator.hh" |
---|
34 | #include "G4TrackStatus.hh" |
---|
35 | #include "G4ParticleChange.hh" |
---|
36 | #include "G4AdjointElectron.hh" |
---|
37 | #include "G4AdjointProton.hh" |
---|
38 | #include "G4AdjointInterpolator.hh" |
---|
39 | #include "G4BetheBlochModel.hh" |
---|
40 | #include "G4BraggIonModel.hh" |
---|
41 | #include "G4Proton.hh" |
---|
42 | #include "G4GenericIon.hh" |
---|
43 | #include "G4NistManager.hh" |
---|
44 | |
---|
45 | //////////////////////////////////////////////////////////////////////////////// |
---|
46 | // |
---|
47 | G4AdjointIonIonisationModel::G4AdjointIonIonisationModel(): |
---|
48 | G4VEmAdjointModel("Adjoint_IonIonisation") |
---|
49 | { |
---|
50 | |
---|
51 | |
---|
52 | UseMatrix =true; |
---|
53 | UseMatrixPerElement = true; |
---|
54 | ApplyCutInRange = true; |
---|
55 | UseOnlyOneMatrixForAllElements = true; |
---|
56 | CS_biasing_factor =1.; |
---|
57 | second_part_of_same_type =false; |
---|
58 | use_only_bragg = false; // for the Ion ionisation using the parametrised table model the cross sections and the sample of secondaries is done |
---|
59 | // as in the BraggIonModel, Therefore the use of this flag; |
---|
60 | |
---|
61 | //The direct EM Model is taken has BetheBloch it is only used for the computation |
---|
62 | // of the differential cross section. |
---|
63 | //The Bragg model could be used as an alternative as it offers the same differential cross section |
---|
64 | |
---|
65 | theBetheBlochDirectEMModel = new G4BetheBlochModel(G4GenericIon::GenericIon()); |
---|
66 | theBraggIonDirectEMModel = new G4BraggIonModel(G4GenericIon::GenericIon()); |
---|
67 | theAdjEquivOfDirectSecondPartDef=G4AdjointElectron::AdjointElectron(); |
---|
68 | theDirectPrimaryPartDef =0; |
---|
69 | theAdjEquivOfDirectPrimPartDef =0; |
---|
70 | /* theDirectPrimaryPartDef =fwd_ion; |
---|
71 | theAdjEquivOfDirectPrimPartDef =adj_ion; |
---|
72 | |
---|
73 | DefineProjectileProperty();*/ |
---|
74 | |
---|
75 | |
---|
76 | |
---|
77 | |
---|
78 | } |
---|
79 | //////////////////////////////////////////////////////////////////////////////// |
---|
80 | // |
---|
81 | G4AdjointIonIonisationModel::~G4AdjointIonIonisationModel() |
---|
82 | {;} |
---|
83 | //////////////////////////////////////////////////////////////////////////////// |
---|
84 | // |
---|
85 | void G4AdjointIonIonisationModel::SampleSecondaries(const G4Track& aTrack, |
---|
86 | G4bool IsScatProjToProjCase, |
---|
87 | G4ParticleChange* fParticleChange) |
---|
88 | { |
---|
89 | const G4DynamicParticle* theAdjointPrimary =aTrack.GetDynamicParticle(); |
---|
90 | |
---|
91 | //Elastic inverse scattering |
---|
92 | //--------------------------------------------------------- |
---|
93 | G4double adjointPrimKinEnergy = theAdjointPrimary->GetKineticEnergy(); |
---|
94 | G4double adjointPrimP =theAdjointPrimary->GetTotalMomentum(); |
---|
95 | |
---|
96 | if (adjointPrimKinEnergy>HighEnergyLimit*0.999){ |
---|
97 | return; |
---|
98 | } |
---|
99 | |
---|
100 | //Sample secondary energy |
---|
101 | //----------------------- |
---|
102 | G4double projectileKinEnergy = SampleAdjSecEnergyFromCSMatrix(adjointPrimKinEnergy, IsScatProjToProjCase); |
---|
103 | CorrectPostStepWeight(fParticleChange, |
---|
104 | aTrack.GetWeight(), |
---|
105 | adjointPrimKinEnergy, |
---|
106 | projectileKinEnergy, |
---|
107 | IsScatProjToProjCase); //Caution !!!this weight correction should be always applied |
---|
108 | |
---|
109 | |
---|
110 | //Kinematic: |
---|
111 | //we consider a two body elastic scattering for the forward processes where the projectile knock on an e- at rest and gives |
---|
112 | // him part of its energy |
---|
113 | //---------------------------------------------------------------------------------------- |
---|
114 | |
---|
115 | G4double projectileM0 = theAdjEquivOfDirectPrimPartDef->GetPDGMass(); |
---|
116 | G4double projectileTotalEnergy = projectileM0+projectileKinEnergy; |
---|
117 | G4double projectileP2 = projectileTotalEnergy*projectileTotalEnergy - projectileM0*projectileM0; |
---|
118 | |
---|
119 | |
---|
120 | |
---|
121 | //Companion |
---|
122 | //----------- |
---|
123 | G4double companionM0 = theAdjEquivOfDirectPrimPartDef->GetPDGMass(); |
---|
124 | if (IsScatProjToProjCase) { |
---|
125 | companionM0=theAdjEquivOfDirectSecondPartDef->GetPDGMass(); |
---|
126 | } |
---|
127 | G4double companionTotalEnergy =companionM0+ projectileKinEnergy-adjointPrimKinEnergy; |
---|
128 | G4double companionP2 = companionTotalEnergy*companionTotalEnergy - companionM0*companionM0; |
---|
129 | |
---|
130 | |
---|
131 | //Projectile momentum |
---|
132 | //-------------------- |
---|
133 | G4double P_parallel = (adjointPrimP*adjointPrimP + projectileP2 - companionP2)/(2.*adjointPrimP); |
---|
134 | G4double P_perp = std::sqrt( projectileP2 - P_parallel*P_parallel); |
---|
135 | G4ThreeVector dir_parallel=theAdjointPrimary->GetMomentumDirection(); |
---|
136 | G4double phi =G4UniformRand()*2.*3.1415926; |
---|
137 | G4ThreeVector projectileMomentum = G4ThreeVector(P_perp*std::cos(phi),P_perp*std::sin(phi),P_parallel); |
---|
138 | projectileMomentum.rotateUz(dir_parallel); |
---|
139 | |
---|
140 | |
---|
141 | |
---|
142 | if (!IsScatProjToProjCase ){ //kill the primary and add a secondary |
---|
143 | fParticleChange->ProposeTrackStatus(fStopAndKill); |
---|
144 | fParticleChange->AddSecondary(new G4DynamicParticle(theAdjEquivOfDirectPrimPartDef,projectileMomentum)); |
---|
145 | //G4cout<<"projectileMomentum "<<projectileMomentum<<G4endl; |
---|
146 | } |
---|
147 | else { |
---|
148 | fParticleChange->ProposeEnergy(projectileKinEnergy); |
---|
149 | fParticleChange->ProposeMomentumDirection(projectileMomentum.unit()); |
---|
150 | } |
---|
151 | |
---|
152 | |
---|
153 | |
---|
154 | |
---|
155 | } |
---|
156 | |
---|
157 | //////////////////////////////////////////////////////////////////////////////// |
---|
158 | // |
---|
159 | G4double G4AdjointIonIonisationModel::DiffCrossSectionPerAtomPrimToSecond( |
---|
160 | G4double kinEnergyProj, |
---|
161 | G4double kinEnergyProd, |
---|
162 | G4double Z, |
---|
163 | G4double A) |
---|
164 | {//Probably that here the Bragg Model should be also used for kinEnergyProj/nuc<2MeV |
---|
165 | |
---|
166 | |
---|
167 | |
---|
168 | G4double dSigmadEprod=0; |
---|
169 | G4double Emax_proj = GetSecondAdjEnergyMaxForProdToProjCase(kinEnergyProd); |
---|
170 | G4double Emin_proj = GetSecondAdjEnergyMinForProdToProjCase(kinEnergyProd); |
---|
171 | |
---|
172 | G4double kinEnergyProjScaled = massRatio*kinEnergyProj; |
---|
173 | |
---|
174 | |
---|
175 | if (kinEnergyProj>Emin_proj && kinEnergyProj<=Emax_proj){ //the produced particle should have a kinetic energy smaller than the projectile |
---|
176 | G4double Tmax=kinEnergyProj; |
---|
177 | |
---|
178 | G4double E1=kinEnergyProd; |
---|
179 | G4double E2=kinEnergyProd*1.000001; |
---|
180 | G4double dE=(E2-E1); |
---|
181 | G4double sigma1,sigma2; |
---|
182 | theDirectEMModel =theBraggIonDirectEMModel; |
---|
183 | if (kinEnergyProjScaled >2.*MeV && !use_only_bragg) theDirectEMModel = theBetheBlochDirectEMModel; //Bethe Bloch Model |
---|
184 | sigma1=theDirectEMModel->ComputeCrossSectionPerAtom(theDirectPrimaryPartDef,kinEnergyProj,Z,A ,E1,1.e20); |
---|
185 | sigma2=theDirectEMModel->ComputeCrossSectionPerAtom(theDirectPrimaryPartDef,kinEnergyProj,Z,A ,E2,1.e20); |
---|
186 | |
---|
187 | dSigmadEprod=(sigma1-sigma2)/dE; |
---|
188 | |
---|
189 | //G4double chargeSqRatio = currentModel->GetChargeSquareRatio(theDirectPrimaryPartDef,currentMaterial,E); |
---|
190 | |
---|
191 | |
---|
192 | |
---|
193 | if (dSigmadEprod>1.) { |
---|
194 | G4cout<<"sigma1 "<<kinEnergyProj/MeV<<'\t'<<kinEnergyProd/MeV<<'\t'<<sigma1<<G4endl; |
---|
195 | G4cout<<"sigma2 "<<kinEnergyProj/MeV<<'\t'<<kinEnergyProd/MeV<<'\t'<<sigma2<<G4endl; |
---|
196 | G4cout<<"dsigma "<<kinEnergyProj/MeV<<'\t'<<kinEnergyProd/MeV<<'\t'<<dSigmadEprod<<G4endl; |
---|
197 | |
---|
198 | } |
---|
199 | |
---|
200 | |
---|
201 | |
---|
202 | |
---|
203 | |
---|
204 | |
---|
205 | if (theDirectEMModel == theBetheBlochDirectEMModel ){ |
---|
206 | //correction of differential cross section at high energy to correct for the suppression of particle at secondary at high |
---|
207 | //energy used in the Bethe Bloch Model. This correction consist to multiply by g the probability function used |
---|
208 | //to test the rejection of a secondary |
---|
209 | //------------------------- |
---|
210 | |
---|
211 | //Source code taken from G4BetheBlochModel::SampleSecondaries |
---|
212 | |
---|
213 | G4double deltaKinEnergy = kinEnergyProd; |
---|
214 | |
---|
215 | //Part of the taken code |
---|
216 | //---------------------- |
---|
217 | |
---|
218 | |
---|
219 | |
---|
220 | // projectile formfactor - suppresion of high energy |
---|
221 | // delta-electron production at high energy |
---|
222 | |
---|
223 | |
---|
224 | G4double x = formfact*deltaKinEnergy; |
---|
225 | if(x > 1.e-6) { |
---|
226 | G4double totEnergy = kinEnergyProj + mass; |
---|
227 | G4double etot2 = totEnergy*totEnergy; |
---|
228 | G4double beta2 = kinEnergyProj*(kinEnergyProj + 2.0*mass)/etot2; |
---|
229 | G4double f; |
---|
230 | G4double f1 = 0.0; |
---|
231 | f = 1.0 - beta2*deltaKinEnergy/Tmax; |
---|
232 | if( 0.5 == spin ) { |
---|
233 | f1 = 0.5*deltaKinEnergy*deltaKinEnergy/etot2; |
---|
234 | f += f1; |
---|
235 | } |
---|
236 | G4double x1 = 1.0 + x; |
---|
237 | G4double g = 1.0/(x1*x1); |
---|
238 | if( 0.5 == spin ) { |
---|
239 | G4double x2 = 0.5*electron_mass_c2*deltaKinEnergy/(mass*mass); |
---|
240 | g *= (1.0 + magMoment2*(x2 - f1/f)/(1.0 + x2)); |
---|
241 | } |
---|
242 | if(g > 1.0) { |
---|
243 | G4cout << "### G4BetheBlochModel in Adjoint Sim WARNING: g= " << g |
---|
244 | << G4endl; |
---|
245 | g=1.; |
---|
246 | } |
---|
247 | //G4cout<<"g"<<g<<G4endl; |
---|
248 | dSigmadEprod*=g; |
---|
249 | } |
---|
250 | } |
---|
251 | |
---|
252 | } |
---|
253 | |
---|
254 | return dSigmadEprod; |
---|
255 | } |
---|
256 | ////////////////////////////////////////////////////////////////////////////////////////////// |
---|
257 | // |
---|
258 | void G4AdjointIonIonisationModel::SetIon(G4ParticleDefinition* adj_ion, G4ParticleDefinition* fwd_ion) |
---|
259 | { theDirectPrimaryPartDef =fwd_ion; |
---|
260 | theAdjEquivOfDirectPrimPartDef =adj_ion; |
---|
261 | |
---|
262 | DefineProjectileProperty(); |
---|
263 | } |
---|
264 | ////////////////////////////////////////////////////////////////////////////////////////////// |
---|
265 | // |
---|
266 | void G4AdjointIonIonisationModel::CorrectPostStepWeight(G4ParticleChange* fParticleChange, G4double old_weight, |
---|
267 | G4double adjointPrimKinEnergy, G4double projectileKinEnergy,G4bool ) |
---|
268 | { |
---|
269 | //It is needed because the direct cross section used to compute the differential cross section is not the one used in |
---|
270 | // the direct model where the GenericIon stuff is considered with correction of effective charge. In the direct model the samnepl of secondaries does |
---|
271 | // not reflect the integral cross section. The integral fwd cross section that we used to compute the differential CS |
---|
272 | // match the sample of secondaries in the forward case despite the fact that its is not the same total CS than in the FWD case. For this reasion an extra |
---|
273 | // weight correction is needed at the end. |
---|
274 | |
---|
275 | |
---|
276 | G4double new_weight=old_weight; |
---|
277 | |
---|
278 | //the correction of CS due to the problem explained above |
---|
279 | G4double kinEnergyProjScaled = massRatio*projectileKinEnergy; |
---|
280 | theDirectEMModel =theBraggIonDirectEMModel; |
---|
281 | if (kinEnergyProjScaled >2.*MeV && !use_only_bragg) theDirectEMModel = theBetheBlochDirectEMModel; //Bethe Bloch Model |
---|
282 | G4double UsedFwdCS=theDirectEMModel->ComputeCrossSectionPerAtom(theDirectPrimaryPartDef,projectileKinEnergy,1,1 ,currentTcutForDirectSecond,1.e20); |
---|
283 | G4double chargeSqRatio =1.; |
---|
284 | if (chargeSquare>1.) chargeSqRatio = theDirectEMModel->GetChargeSquareRatio(theDirectPrimaryPartDef,currentMaterial,projectileKinEnergy); |
---|
285 | G4double CorrectFwdCS = chargeSqRatio*theDirectEMModel->ComputeCrossSectionPerAtom(G4GenericIon::GenericIon(),kinEnergyProjScaled,1,1 ,currentTcutForDirectSecond,1.e20); |
---|
286 | if (UsedFwdCS >0) new_weight*= CorrectFwdCS/UsedFwdCS;//May be some check is needed if UsedFwdCS ==0 probably that then we should avoid a secondary to be produced, |
---|
287 | |
---|
288 | |
---|
289 | //additional CS crorrection needed for cross section biasing in general. |
---|
290 | //May be wrong for ions!!! Most of the time not used! |
---|
291 | G4double w_corr =1./CS_biasing_factor; |
---|
292 | w_corr*=G4AdjointCSManager::GetAdjointCSManager()->GetPostStepWeightCorrection(); |
---|
293 | new_weight*=w_corr; |
---|
294 | |
---|
295 | new_weight*=projectileKinEnergy/adjointPrimKinEnergy; |
---|
296 | |
---|
297 | fParticleChange->SetParentWeightByProcess(false); |
---|
298 | fParticleChange->SetSecondaryWeightByProcess(false); |
---|
299 | fParticleChange->ProposeParentWeight(new_weight); |
---|
300 | } |
---|
301 | |
---|
302 | |
---|
303 | ////////////////////////////////////////////////////////////////////////////////////////////// |
---|
304 | // |
---|
305 | void G4AdjointIonIonisationModel::DefineProjectileProperty() |
---|
306 | { |
---|
307 | //Slightly modified code taken from G4BetheBlochModel::SetParticle |
---|
308 | //------------------------------------------------ |
---|
309 | G4String pname = theDirectPrimaryPartDef->GetParticleName(); |
---|
310 | if (theDirectPrimaryPartDef->GetParticleType() == "nucleus" && |
---|
311 | pname != "deuteron" && pname != "triton") { |
---|
312 | isIon = true; |
---|
313 | } |
---|
314 | |
---|
315 | mass = theDirectPrimaryPartDef->GetPDGMass(); |
---|
316 | massRatio= G4GenericIon::GenericIon()->GetPDGMass()/mass; |
---|
317 | spin = theDirectPrimaryPartDef->GetPDGSpin(); |
---|
318 | G4double q = theDirectPrimaryPartDef->GetPDGCharge()/eplus; |
---|
319 | chargeSquare = q*q; |
---|
320 | ratio = electron_mass_c2/mass; |
---|
321 | ratio2 = ratio*ratio; |
---|
322 | one_plus_ratio_2=(1+ratio)*(1+ratio); |
---|
323 | one_minus_ratio_2=(1-ratio)*(1-ratio); |
---|
324 | G4double magmom = theDirectPrimaryPartDef->GetPDGMagneticMoment() |
---|
325 | *mass/(0.5*eplus*hbar_Planck*c_squared); |
---|
326 | magMoment2 = magmom*magmom - 1.0; |
---|
327 | formfact = 0.0; |
---|
328 | if(theDirectPrimaryPartDef->GetLeptonNumber() == 0) { |
---|
329 | G4double x = 0.8426*GeV; |
---|
330 | if(spin == 0.0 && mass < GeV) {x = 0.736*GeV;} |
---|
331 | else if(mass > GeV) { |
---|
332 | x /= G4NistManager::Instance()->GetZ13(mass/proton_mass_c2); |
---|
333 | // tlimit = 51.2*GeV*A13[iz]*A13[iz]; |
---|
334 | } |
---|
335 | formfact = 2.0*electron_mass_c2/(x*x); |
---|
336 | tlimit = 2.0/formfact; |
---|
337 | } |
---|
338 | } |
---|
339 | |
---|
340 | |
---|
341 | ////////////////////////////////////////////////////////////////////////////// |
---|
342 | // |
---|
343 | G4double G4AdjointIonIonisationModel::GetSecondAdjEnergyMaxForScatProjToProjCase(G4double PrimAdjEnergy) |
---|
344 | { |
---|
345 | G4double Tmax=PrimAdjEnergy*one_plus_ratio_2/(one_minus_ratio_2-2.*ratio*PrimAdjEnergy/mass); |
---|
346 | return Tmax; |
---|
347 | } |
---|
348 | ////////////////////////////////////////////////////////////////////////////// |
---|
349 | // |
---|
350 | G4double G4AdjointIonIonisationModel::GetSecondAdjEnergyMinForScatProjToProjCase(G4double PrimAdjEnergy,G4double Tcut) |
---|
351 | { return PrimAdjEnergy+Tcut; |
---|
352 | } |
---|
353 | ////////////////////////////////////////////////////////////////////////////// |
---|
354 | // |
---|
355 | G4double G4AdjointIonIonisationModel::GetSecondAdjEnergyMaxForProdToProjCase(G4double ) |
---|
356 | { return HighEnergyLimit; |
---|
357 | } |
---|
358 | ////////////////////////////////////////////////////////////////////////////// |
---|
359 | // |
---|
360 | G4double G4AdjointIonIonisationModel::GetSecondAdjEnergyMinForProdToProjCase(G4double PrimAdjEnergy) |
---|
361 | { G4double Tmin= (2*PrimAdjEnergy-4*mass + std::sqrt(4.*PrimAdjEnergy*PrimAdjEnergy +16.*mass*mass + 8.*PrimAdjEnergy*mass*(1/ratio +ratio)))/4.; |
---|
362 | return Tmin; |
---|
363 | } |
---|