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25 //
26 // 24.11.08 V. Grichine - first implementation
27 //
28 // 04.09.18 V. Ivantchenko Major revision of interfaces and implementation
29 // 27.05.19 V. Ivantchenko Removed obsolete methods and members
30
31 #include "G4ComponentGGNuclNuclXsc.hh"
32
33 #include "G4PhysicalConstants.hh"
34 #include "G4SystemOfUnits.hh"
35 #include "G4NucleiProperties.hh"
36 #include "G4ParticleDefinition.hh"
37 #include "G4HadronNucleonXsc.hh"
38 #include "G4ComponentGGHadronNucleusXsc.hh"
39 #include "G4NuclearRadii.hh"
40 #include "G4Pow.hh"
41
42 namespace
43 {
44 const G4double inve = 1./CLHEP::eplus;
45 }
46
47 G4ComponentGGNuclNuclXsc::G4ComponentGGNuclNuclXsc()
48 : G4VComponentCrossSection("Glauber-Gribov Nucl-nucl")
49 {
50 theProton = G4Proton::Proton();
51 theNeutron = G4Neutron::Neutron();
52 theLambda = G4Lambda::Lambda();
53 fHNXsc = new G4HadronNucleonXsc();
54 fHadrNucl = new G4ComponentGGHadronNucleusXsc();
55 }
56
57 G4ComponentGGNuclNuclXsc::~G4ComponentGGNuclNuclXsc()
58 {
59 delete fHNXsc;
60 }
61
62 //////////////////////////////////////////////////////////////////////
63
64 G4double G4ComponentGGNuclNuclXsc::GetTotalElementCrossSection(
65 const G4ParticleDefinition* aParticle, G4double kinEnergy,
66 G4int Z, G4double A)
67 {
68 ComputeCrossSections(aParticle, kinEnergy, Z, G4lrint(A));
69 return fTotalXsc;
70 }
71
72 ////////////////////////////////////////////////////////////////////
73
74 G4double G4ComponentGGNuclNuclXsc::GetTotalIsotopeCrossSection(
75 const G4ParticleDefinition* aParticle, G4double kinEnergy,
76 G4int Z, G4int A)
77 {
78 ComputeCrossSections(aParticle, kinEnergy, Z, A);
79 return fTotalXsc;
80 }
81
82 /////////////////////////////////////////////////////////////////////
83
84 G4double G4ComponentGGNuclNuclXsc::GetInelasticElementCrossSection(
85 const G4ParticleDefinition* aParticle, G4double kinEnergy,
86 G4int Z, G4double A)
87 {
88 ComputeCrossSections(aParticle, kinEnergy, Z, G4lrint(A));
89 return fInelasticXsc;
90 }
91
92 ////////////////////////////////////////////////////////////////////
93
94 G4double G4ComponentGGNuclNuclXsc::GetInelasticIsotopeCrossSection(
95 const G4ParticleDefinition* aParticle, G4double kinEnergy,
96 G4int Z, G4int A)
97 {
98 ComputeCrossSections(aParticle, kinEnergy, Z, A);
99 return fInelasticXsc;
100 }
101
102 //////////////////////////////////////////////////////////////////
103
104 G4double G4ComponentGGNuclNuclXsc::GetElasticElementCrossSection(
105 const G4ParticleDefinition* aParticle, G4double kinEnergy,
106 G4int Z, G4double A)
107 {
108 ComputeCrossSections(aParticle, kinEnergy, Z, G4lrint(A));
109 return fElasticXsc;
110 }
111
112 ///////////////////////////////////////////////////////////////////
113
114 G4double G4ComponentGGNuclNuclXsc::GetElasticIsotopeCrossSection(
115 const G4ParticleDefinition* aParticle, G4double kinEnergy,
116 G4int Z, G4int A)
117 {
118 ComputeCrossSections(aParticle, kinEnergy, Z, A);
119 return fElasticXsc;
120 }
121
122 ////////////////////////////////////////////////////////////////
123
124 G4double G4ComponentGGNuclNuclXsc::ComputeQuasiElasticRatio(
125 const G4ParticleDefinition* aParticle, G4double kinEnergy,
126 G4int Z, G4int A)
127 {
128 ComputeCrossSections(aParticle, kinEnergy, Z, A);
129 return (fInelasticXsc > fProductionXsc)
130 ? (fInelasticXsc - fProductionXsc)/fInelasticXsc : 0.0;
131 }
132
133 //////////////////////////////////////////////////////////////////////
134
135 void G4ComponentGGNuclNuclXsc::BuildPhysicsTable(const G4ParticleDefinition&)
136 {}
137
138 //////////////////////////////////////////////////////////////////////
139
140 void G4ComponentGGNuclNuclXsc::DumpPhysicsTable(const G4ParticleDefinition&)
141 {
142 G4cout << "G4ComponentGGNuclNuclXsc: uses Glauber-Gribov formula" << G4endl;
143 }
144
145 //////////////////////////////////////////////////////////////////////
146
147 void G4ComponentGGNuclNuclXsc::Description(std::ostream& outFile) const
148 {
149 outFile << "G4ComponentGGNuclNuclXsc calculates total, inelastic and\n"
150 << "elastic cross sections for nucleus-nucleus collisions using\n"
151 << "the Glauber model with Gribov corrections. It is valid for\n"
152 << "all incident energies above 100 keV./n"
153 << "For the hydrogen target G4HadronNucleonXsc class is used.\n";
154 }
155
156 ///////////////////////////////////////////////////////////////////////////////
157 //
158 // Calculates total and inelastic Xsc, derives elastic as total - inelastic
159 // accordong to Glauber model with Gribov correction calculated in the dipole
160 // approximation on light cone. Gaussian density of point-like nucleons helps
161 // to calculate rest integrals of the model. [1] B.Z. Kopeliovich,
162 // nucl-th/0306044 + simplification above
163
164 void G4ComponentGGNuclNuclXsc::ComputeCrossSections(
165 const G4ParticleDefinition* aParticle, G4double kinEnergy,
166 G4int Z, G4int A)
167 {
168 // check cache
169 if(aParticle == fParticle && fZ == Z && fA == A && kinEnergy == fEnergy)
170 { return; }
171 fParticle = aParticle;
172 fZ = Z;
173 fA = A;
174 fEnergy = kinEnergy;
175 G4Pow* pG4Pow = G4Pow::GetInstance();
176
177 G4int pZ = G4lrint(aParticle->GetPDGCharge()*inve);
178 G4int pA = aParticle->GetBaryonNumber();
179 G4int pL = aParticle->GetNumberOfLambdasInHypernucleus();
180 G4bool pHN = aParticle->IsHypernucleus();
181 G4double cHN(0.88);
182
183 // hydrogen
184 if(1 == Z && 1 == A) {
185 G4double e = kinEnergy*CLHEP::proton_mass_c2/aParticle->GetPDGMass();
186 fHadrNucl->ComputeCrossSections( theProton, e, pZ, pA, pL );
187 fTotalXsc = fHadrNucl->GetTotalGlauberGribovXsc();
188 fElasticXsc = fHadrNucl->GetElasticGlauberGribovXsc();
189 fInelasticXsc = fHadrNucl->GetInelasticGlauberGribovXsc();
190 fProductionXsc = fHadrNucl->GetProductionGlauberGribovXsc();
191 fDiffractionXsc = fHadrNucl->GetDiffractionGlauberGribovXsc();
192 return;
193 }
194 static const G4double cofInelastic = 2.4;
195 static const G4double cofTotal = 2.0;
196
197 G4double pTkin = kinEnergy/(G4double)pA;
198
199 G4int pN = pA - pZ;
200 G4int tN = A - Z;
201
202 G4double tR = G4NuclearRadii::Radius(Z, A);
203 G4double pR = G4NuclearRadii::Radius(pZ, pA);
204
205 if(pHN)
206 pR *= std::sqrt( pG4Pow->Z23( pA - pL ) + cHN*pG4Pow->Z23( pL ) )/pG4Pow->Z13(pA);
207
208 G4double cB = ComputeCoulombBarier(aParticle, kinEnergy, Z, A, pR, tR);
209
210 if ( cB > 0. )
211 {
212 G4double sigma = (pZ*Z+pN*tN)*fHNXsc->HadronNucleonXscNS(theProton, theProton, pTkin);
213 if(pHN) sigma += pL*A*fHNXsc->HadronNucleonXsc(theLambda, theProton, pTkin);
214 G4double ppInXsc = fHNXsc->GetInelasticHadronNucleonXsc();
215
216 sigma += (pZ*tN+pN*Z)*fHNXsc->HadronNucleonXscNS(theNeutron, theProton, pTkin);
217 G4double npInXsc = fHNXsc->GetInelasticHadronNucleonXsc();
218
219 G4double nucleusSquare = cofTotal*CLHEP::pi*( pR*pR + tR*tR ); // basically 2piRR
220
221 G4double ratio= sigma/nucleusSquare;
222 fTotalXsc = nucleusSquare*G4Log( 1. + ratio )*cB;
223 fInelasticXsc = nucleusSquare*G4Log( 1. + cofInelastic*ratio )*cB/cofInelastic;
224 fElasticXsc = std::max(fTotalXsc - fInelasticXsc, 0.0);
225
226 G4double difratio = ratio/(1.+ratio);
227 fDiffractionXsc = 0.5*nucleusSquare*( difratio - G4Log( 1. + difratio ) );
228
229 G4double xratio= ((pZ*Z+pN*tN)*ppInXsc + (pZ*tN+pN*Z)*npInXsc)/nucleusSquare;
230 fProductionXsc = nucleusSquare*G4Log( 1. + cofInelastic*xratio)*cB/cofInelastic;
231 fProductionXsc = std::min(fProductionXsc, fInelasticXsc);
232 }
233 else
234 {
235 fInelasticXsc = fTotalXsc = fElasticXsc = fProductionXsc = fDiffractionXsc = 0.;
236 }
237 }
238
239 ///////////////////////////////////////////////////////////////////////////////
240
241 G4double G4ComponentGGNuclNuclXsc::ComputeCoulombBarier(
242 const G4ParticleDefinition* aParticle,
243 G4double pTkin, G4int Z, G4int A,
244 G4double pR, G4double tR)
245 {
246 G4int pZ = aParticle->GetPDGCharge()*inve;
247 G4double pM = aParticle->GetPDGMass();
248 G4double tM = G4NucleiProperties::GetNuclearMass(A, Z);
249 G4double pElab = pTkin + pM;
250 G4double totEcm = std::sqrt(pM*pM + tM*tM + 2.*pElab*tM);
251 G4double totTcm = totEcm - pM -tM;
252
253 // 0.5 defines shape of Cross section correction
254 // at cB = totTcm it become zero
255 static const G4double qfact = 0.5*CLHEP::elm_coupling;
256 G4double bC = qfact*pZ*Z/(pR + tR);
257
258 G4double ratio = (totTcm <= bC) ? 0. : 1. - bC/totTcm;
259
260 #ifdef G4VERBOSE
261 if (GetVerboseLevel() > 1) {
262 G4cout << "G4ComponentGGNuclNuclXsc::ComputeCoulombBarier(..)=" <<ratio
263 << "; pTkin(GeV)=" << pTkin/CLHEP::MeV
264 << " totTcm= " << totTcm/CLHEP::MeV<< "; bC=" << bC/CLHEP::MeV
265 << G4endl;
266 }
267 #endif
268 return ratio;
269 }
270
271 //////////////////////////////////////////////////////////////////////////
272 //
273 // Return single-diffraction/inelastic cross-section ratio
274
275 G4double G4ComponentGGNuclNuclXsc::GetRatioSD(
276 const G4DynamicParticle* aParticle, G4double tA, G4double tZ)
277 {
278 ComputeCrossSections(aParticle->GetDefinition(),
279 aParticle->GetKineticEnergy(),
280 G4lrint(tZ), G4lrint(tA));
281
282 return (fInelasticXsc > 0.0) ? fDiffractionXsc/fInelasticXsc : 0.0;
283 }
284
285 //////////////////////////////////////////////////////////////////////////
286 //
287 // Return quasi-elastic/inelastic cross-section ratio
288
289 G4double G4ComponentGGNuclNuclXsc::GetRatioQE(
290 const G4DynamicParticle* aParticle, G4double tA, G4double tZ)
291 {
292 ComputeCrossSections(aParticle->GetDefinition(),
293 aParticle->GetKineticEnergy(),
294 G4lrint(tZ), G4lrint(tA));
295
296 return (fInelasticXsc > 0.0) ? 1.0 - fProductionXsc/fInelasticXsc : 0.0;
297 }
298
299 ///////////////////////////////////////////////////////////////////////////////
300