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25 //
26 // G4RKFieldIntegrator
27 #include "G4RKFieldIntegrator.hh"
28 #include "G4PhysicalConstants.hh"
29 #include "G4SystemOfUnits.hh"
30 #include "G4NucleiProperties.hh"
31 #include "G4FermiMomentum.hh"
32 #include "G4NuclearFermiDensity.hh"
33 #include "G4NuclearShellModelDensity.hh"
34 #include "G4Nucleon.hh"
35 #include "G4Exp.hh"
36 #include "G4Log.hh"
37 #include "G4Pow.hh"
38
39 // Class G4RKFieldIntegrator
40 //*************************************************************************************************************************************
41
42 // only theActive are propagated, nothing else
43 // only theSpectators define the field, nothing else
44
45 void G4RKFieldIntegrator::Transport(G4KineticTrackVector &theActive, const G4KineticTrackVector &theSpectators, G4double theTimeStep)
46 {
47 (void)theActive;
48 (void)theSpectators;
49 (void)theTimeStep;
50 }
51
52
53 G4double G4RKFieldIntegrator::CalculateTotalEnergy(const G4KineticTrackVector& Barions)
54 {
55 const G4double Alpha = 0.25/fermi/fermi;
56 const G4double t1 = -7264.04*fermi*fermi*fermi;
57 const G4double tGamma = 87.65*fermi*fermi*fermi*fermi*fermi*fermi;
58 // const G4double Gamma = 1.676;
59 const G4double Vo = -0.498*fermi;
60 const G4double GammaY = 1.4*fermi;
61
62 G4double Etot = 0;
63 G4int nBarion = (G4int)Barions.size();
64 for(G4int c1 = 0; c1 < nBarion; ++c1)
65 {
66 G4KineticTrack* p1 = Barions.operator[](c1);
67 // Ekin
68 Etot += p1->Get4Momentum().e();
69 for(G4int c2 = c1 + 1; c2 < nBarion; ++c2)
70 {
71 G4KineticTrack* p2 = Barions.operator[](c2);
72 G4double r12 = (p1->GetPosition() - p2->GetPosition()).mag()*fermi;
73
74 // Esk2
75 Etot += t1*G4Pow::GetInstance()->A23(Alpha/pi)*G4Exp(-Alpha*r12*r12);
76
77 // Eyuk
78 Etot += Vo*0.5/r12*G4Exp(1/(4*Alpha*GammaY*GammaY))*
79 (G4Exp(-r12/GammaY)*(1 - Erf(0.5/GammaY/std::sqrt(Alpha) - std::sqrt(Alpha)*r12)) -
80 G4Exp( r12/GammaY)*(1 - Erf(0.5/GammaY/std::sqrt(Alpha) + std::sqrt(Alpha)*r12)));
81
82 // Ecoul
83 Etot += 1.44*p1->GetDefinition()->GetPDGCharge()*p2->GetDefinition()->GetPDGCharge()/r12*Erf(std::sqrt(Alpha)*r12);
84
85 // Epaul
86 Etot = 0;
87
88 for(G4int c3 = c2 + 1; c3 < nBarion; c3++)
89 {
90 G4KineticTrack* p3 = Barions.operator[](c3);
91 G4double r13 = (p1->GetPosition() - p3->GetPosition()).mag()*fermi;
92
93 // Esk3
94 Etot = tGamma*G4Pow::GetInstance()->powA(4*Alpha*Alpha/3/pi/pi, 1.5)*G4Exp(-Alpha*(r12*r12 + r13*r13));
95 }
96 }
97 }
98 return Etot;
99 }
100
101 //************************************************************************************************
102 // originated from the Numerical recipes error function
103 G4double G4RKFieldIntegrator::Erf(G4double X)
104 {
105 const G4double Z1 = 1;
106 const G4double HF = Z1/2;
107 const G4double C1 = 0.56418958;
108
109 const G4double P10 = +3.6767877;
110 const G4double Q10 = +3.2584593;
111 const G4double P11 = -9.7970465E-2;
112
113 // static G4ThreadLocal G4double P2[5] = { 7.3738883, 6.8650185, 3.0317993, 0.56316962, 4.3187787e-5 };
114 // static G4ThreadLocal G4double Q2[5] = { 7.3739609, 15.184908, 12.79553, 5.3542168, 1. };
115 const G4double P2[5] = { 7.3738883, 6.8650185, 3.0317993, 0.56316962, 4.3187787e-5 };
116 const G4double Q2[5] = { 7.3739609, 15.184908, 12.79553, 5.3542168, 1. };
117
118 const G4double P30 = -1.2436854E-1;
119 const G4double Q30 = +4.4091706E-1;
120 const G4double P31 = -9.6821036E-2;
121
122 G4double V = std::abs(X);
123 G4double H;
124 G4double Y;
125 G4int c1;
126
127 if(V < HF)
128 {
129 Y = V*V;
130 H = X*(P10 + P11*Y)/(Q10+Y);
131 }
132 else
133 {
134 if(V < 4)
135 {
136 G4double AP = P2[4];
137 G4double AQ = Q2[4];
138 for(c1 = 3; c1 >= 0; c1--)
139 {
140 AP = P2[c1] + V*AP;
141 AQ = Q2[c1] + V*AQ;
142 }
143 H = 1 - G4Exp(-V*V)*AP/AQ;
144 }
145 else
146 {
147 Y = 1./V*V;
148 H = 1 - G4Exp(-V*V)*(C1+Y*(P30 + P31*Y)/(Q30 + Y))/V;
149 }
150 if (X < 0)
151 H = -H;
152 }
153 return H;
154 }
155
156 //************************************************************************************************
157 //This is a QMD version to calculate excitation energy of a fragment,
158 //which consists from G4KTV &the Particles
159 /*
160 G4double G4RKFieldIntegrator::GetExcitationEnergy(const G4KineticTrackVector &theParticles)
161 {
162 // Excitation energy of a fragment consisting from A nucleons and Z protons
163 // is Etot - Z*Mp - (A - Z)*Mn - B(A, Z), where B(A,Z) is the binding energy of fragment
164 // and Mp, Mn are proton and neutron mass, respectively.
165 G4int NZ = 0;
166 G4int NA = 0;
167 G4double Etot = CalculateTotalEnergy(theParticles);
168 for(G4int cParticle = 0; cParticle < theParticles.length(); cParticle++)
169 {
170 G4KineticTrack* pKineticTrack = theParticles.at(cParticle);
171 G4int Encoding = std::abs(pKineticTrack->GetDefinition()->GetPDGEncoding());
172 if (Encoding == 2212)
173 NZ++, NA++;
174 if (Encoding == 2112)
175 NA++;
176 Etot -= pKineticTrack->GetDefinition()->GetPDGMass();
177 }
178 return Etot - G4NucleiProperties::GetBindingEnergy(NZ, NA);
179 }
180 */
181
182 //*************************************************************************************************************************************
183 //This is a simplified method to get excitation energy of a residual
184 // nucleus with nHitNucleons.
185 G4double G4RKFieldIntegrator::GetExcitationEnergy(G4int nHitNucleons, const G4KineticTrackVector &)
186 {
187 const G4double MeanE = 50;
188 G4double Sum = 0;
189 for(G4int c1 = 0; c1 < nHitNucleons; ++c1)
190 {
191 Sum += -MeanE*G4Log(G4UniformRand());
192 }
193 return Sum;
194 }
195 //*************************************************************************************************************************************
196
197 /*
198 //This is free propagation of particles for CASCADE mode. Target nucleons should be frozen
199 void G4RKFieldIntegrator::Integrate(G4KineticTrackVector& theParticles)
200 {
201 for(G4int cParticle = 0; cParticle < theParticles.length(); ++cParticle)
202 {
203 G4KineticTrack* pKineticTrack = theParticles.at(cParticle);
204 pKineticTrack->SetPosition(pKineticTrack->GetPosition() + theTimeStep*pKineticTrack->Get4Momentum().boostVector());
205 }
206 }
207 */
208 //*************************************************************************************************************************************
209
210 void G4RKFieldIntegrator::Integrate(const G4KineticTrackVector& theBarions, G4double theTimeStep)
211 {
212 for(std::size_t cParticle = 0; cParticle < theBarions.size(); ++cParticle)
213 {
214 G4KineticTrack* pKineticTrack = theBarions[cParticle];
215 pKineticTrack->SetPosition(pKineticTrack->GetPosition() + theTimeStep*pKineticTrack->Get4Momentum().boostVector());
216 }
217 }
218
219 //*************************************************************************************************************************************
220
221 // constant to calculate theCoulomb barrier
222 const G4double G4RKFieldIntegrator::coulomb = 1.44 / 1.14 * MeV;
223
224 // kaon's potential constant (real part only)
225 // 0.35 + i0.82 or 0.63 + i0.89 fermi
226 const G4double G4RKFieldIntegrator::a_kaon = 0.35;
227
228 // pion's potential constant (real part only)
229 //!! for pions it has todiffer from kaons
230 // 0.35 + i0.82 or 0.63 + i0.89 fermi
231 const G4double G4RKFieldIntegrator::a_pion = 0.35;
232
233 // antiproton's potential constant (real part only)
234 // 1.53 + i2.50 fermi
235 const G4double G4RKFieldIntegrator::a_antiproton = 1.53;
236
237 // methods for calculating potentials for different types of particles
238 // aPosition is relative to the nucleus center
239 G4double G4RKFieldIntegrator::GetNeutronPotential(G4double )
240 {
241 /*
242 const G4double Mn = 939.56563 * MeV; // mass of nuetron
243
244 G4VNuclearDensity *theDencity;
245 if(theA < 17) theDencity = new G4NuclearShellModelDensity(theA, theZ);
246 else theDencity = new G4NuclearFermiDensity(theA, theZ);
247
248 // GetDencity() accepts only G4ThreeVector so build it:
249 G4ThreeVector aPosition(0.0, 0.0, radius);
250 G4double density = theDencity->GetDensity(aPosition);
251 delete theDencity;
252
253 G4FermiMomentum *fm = new G4FermiMomentum();
254 fm->Init(theA, theZ);
255 G4double fermiMomentum = fm->GetFermiMomentum(density);
256 delete fm;
257
258 return sqr(fermiMomentum)/(2 * Mn)
259 + G4CreateNucleus::GetBindingEnergy(theZ, theA)/theA;
260 //+ G4NucleiProperties::GetBindingEnergy(theZ, theA)/theA;
261 */
262
263 return 0.0;
264 }
265
266 G4double G4RKFieldIntegrator::GetProtonPotential(G4double )
267 {
268 /*
269 // calculate Coulomb barrier value
270 G4double theCoulombBarrier = coulomb * theZ/(1. + G4Pow::GetInstance()->Z13(theA));
271 const G4double Mp = 938.27231 * MeV; // mass of proton
272
273 G4VNuclearDensity *theDencity;
274 if(theA < 17) theDencity = new G4NuclearShellModelDensity(theA, theZ);
275 else theDencity = new G4NuclearFermiDensity(theA, theZ);
276
277 // GetDencity() accepts only G4ThreeVector so build it:
278 G4ThreeVector aPosition(0.0, 0.0, radius);
279 G4double density = theDencity->GetDensity(aPosition);
280 delete theDencity;
281
282 G4FermiMomentum *fm = new G4FermiMomentum();
283 fm->Init(theA, theZ);
284 G4double fermiMomentum = fm->GetFermiMomentum(density);
285 delete fm;
286
287 return sqr(fermiMomentum)/ (2 * Mp)
288 + G4CreateNucleus::GetBindingEnergy(theZ, theA)/theA;
289 //+ G4NucleiProperties::GetBindingEnergy(theZ, theA)/theA
290 + theCoulombBarrier;
291 */
292
293 return 0.0;
294 }
295
296 G4double G4RKFieldIntegrator::GetAntiprotonPotential(G4double )
297 {
298 /*
299 //G4double theM = G4NucleiProperties::GetAtomicMass(theA, theZ);
300 G4double theM = theZ * G4Proton::Proton()->GetPDGMass()
301 + (theA - theZ) * G4Neutron::Neutron()->GetPDGMass()
302 + G4CreateNucleus::GetBindingEnergy(theZ, theA);
303
304 const G4double Mp = 938.27231 * MeV; // mass of proton
305 G4double mu = (theM * Mp)/(theM + Mp);
306
307 // antiproton's potential coefficient
308 // V = coeff_antiproton * nucleus_density
309 G4double coeff_antiproton = -2.*pi/mu * (1. + Mp) * a_antiproton;
310
311 G4VNuclearDensity *theDencity;
312 if(theA < 17) theDencity = new G4NuclearShellModelDensity(theA, theZ);
313 else theDencity = new G4NuclearFermiDensity(theA, theZ);
314
315 // GetDencity() accepts only G4ThreeVector so build it:
316 G4ThreeVector aPosition(0.0, 0.0, radius);
317 G4double density = theDencity->GetDensity(aPosition);
318 delete theDencity;
319
320 return coeff_antiproton * density;
321 */
322
323 return 0.0;
324 }
325
326 G4double G4RKFieldIntegrator::GetKaonPotential(G4double )
327 {
328 /*
329 //G4double theM = G4NucleiProperties::GetAtomicMass(theA, theZ);
330 G4double theM = theZ * G4Proton::Proton()->GetPDGMass()
331 + (theA - theZ) * G4Neutron::Neutron()->GetPDGMass()
332 + G4CreateNucleus::GetBindingEnergy(theZ, theA);
333
334 const G4double Mk = 496. * MeV; // mass of "kaon"
335 G4double mu = (theM * Mk)/(theM + Mk);
336
337 // kaon's potential coefficient
338 // V = coeff_kaon * nucleus_density
339 G4double coeff_kaon = -2.*pi/mu * (1. + Mk/theM) * a_kaon;
340
341 G4VNuclearDensity *theDencity;
342 if(theA < 17) theDencity = new G4NuclearShellModelDensity(theA, theZ);
343 else theDencity = new G4NuclearFermiDensity(theA, theZ);
344
345 // GetDencity() accepts only G4ThreeVector so build it:
346 G4ThreeVector aPosition(0.0, 0.0, radius);
347 G4double density = theDencity->GetDensity(aPosition);
348 delete theDencity;
349
350 return coeff_kaon * density;
351 */
352
353 return 0.0;
354 }
355
356 G4double G4RKFieldIntegrator::GetPionPotential(G4double )
357 {
358 /*
359 //G4double theM = G4NucleiProperties::GetAtomicMass(theA, theZ);
360 G4double theM = theZ * G4Proton::Proton()->GetPDGMass()
361 + (theA - theZ) * G4Neutron::Neutron()->GetPDGMass()
362 + G4CreateNucleus::GetBindingEnergy(theZ, theA);
363
364 const G4double Mpi = 139. * MeV; // mass of "pion"
365 G4double mu = (theM * Mpi)/(theM + Mpi);
366
367 // pion's potential coefficient
368 // V = coeff_pion * nucleus_density
369 G4double coeff_pion = -2.*pi/mu * (1. + Mpi) * a_pion;
370
371 G4VNuclearDensity *theDencity;
372 if(theA < 17) theDencity = new G4NuclearShellModelDensity(theA, theZ);
373 else theDencity = new G4NuclearFermiDensity(theA, theZ);
374
375 // GetDencity() accepts only G4ThreeVector so build it:
376 G4ThreeVector aPosition(0.0, 0.0, radius);
377 G4double density = theDencity->GetDensity(aPosition);
378 delete theDencity;
379
380 return coeff_pion * density;
381 */
382
383 return 0.0;
384 }
385