G4ComponentGGNuclNuclXsc.cc

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00025 //
00026 // 24.11.08 V. Grichine - first implementation
00027 //
00028 
00029 #include "G4ComponentGGNuclNuclXsc.hh"
00030 
00031 #include "G4PhysicalConstants.hh"
00032 #include "G4SystemOfUnits.hh"
00033 #include "G4ParticleTable.hh"
00034 #include "G4IonTable.hh"
00035 #include "G4ParticleDefinition.hh"
00036 #include "G4HadTmpUtil.hh"
00037 #include "G4HadronNucleonXsc.hh"
00038 
00039 
00040 G4ComponentGGNuclNuclXsc::G4ComponentGGNuclNuclXsc() 
00041  : G4VComponentCrossSection("Glauber-Gribov nucleus nucleus"),
00042    fUpperLimit(100000*GeV), fLowerLimit(0.1*MeV),
00043    fRadiusConst(1.08*fermi),  // 1.1, 1.3 ?
00044    fTotalXsc(0.0), fElasticXsc(0.0), fInelasticXsc(0.0), fProductionXsc(0.0),
00045    fDiffractionXsc(0.0), fHadronNucleonXsc(0.0)
00046 {
00047   theProton   = G4Proton::Proton();
00048   theNeutron  = G4Neutron::Neutron();
00049   hnXsc = new G4HadronNucleonXsc();
00050 }
00051 
00052 
00053 G4ComponentGGNuclNuclXsc::~G4ComponentGGNuclNuclXsc()
00054 {
00055   delete hnXsc;
00056 }
00057 
00059 
00060 G4double G4ComponentGGNuclNuclXsc::GetTotalIsotopeCrossSection(const G4ParticleDefinition* aParticle,
00061                                        G4double kinEnergy,
00062                                        G4int Z, G4int A)
00063 {
00064   G4DynamicParticle* aDP = new G4DynamicParticle(aParticle,G4ParticleMomentum(1.,0.,0.), 
00065                                                 kinEnergy);
00066   fInelasticXsc = GetZandACrossSection(aDP, Z, A);
00067   delete aDP;
00068 
00069   return fTotalXsc;
00070 }
00071 
00073 
00074 G4double G4ComponentGGNuclNuclXsc::GetTotalElementCrossSection(const G4ParticleDefinition* aParticle,
00075                                        G4double kinEnergy, 
00076                                        G4int Z, G4double A)
00077 {
00078   G4DynamicParticle* aDP = new G4DynamicParticle(aParticle,G4ParticleMomentum(1.,0.,0.), 
00079                                                 kinEnergy);
00080   fInelasticXsc = GetZandACrossSection(aDP, Z, G4int(A));
00081   delete aDP;
00082 
00083   return fTotalXsc;
00084 }
00085 
00087 
00088 G4double G4ComponentGGNuclNuclXsc::GetInelasticIsotopeCrossSection(const G4ParticleDefinition* aParticle,
00089                                            G4double kinEnergy, 
00090                                            G4int Z, G4int A)
00091 {
00092   G4DynamicParticle* aDP = new G4DynamicParticle(aParticle,G4ParticleMomentum(1.,0.,0.), 
00093                                                 kinEnergy);
00094   fInelasticXsc = GetZandACrossSection(aDP, Z, A);
00095   delete aDP;
00096 
00097   return fInelasticXsc;
00098 }
00099 
00101 
00102 G4double G4ComponentGGNuclNuclXsc::GetInelasticElementCrossSection(const G4ParticleDefinition* aParticle,
00103                                            G4double kinEnergy, 
00104                                            G4int Z, G4double A)
00105 {
00106   G4DynamicParticle* aDP = new G4DynamicParticle(aParticle,G4ParticleMomentum(1.,0.,0.), 
00107                                                 kinEnergy);
00108   fInelasticXsc = GetZandACrossSection(aDP, Z, G4int(A));
00109   delete aDP;
00110 
00111   return fInelasticXsc;
00112 }
00113 
00115 
00116 G4double G4ComponentGGNuclNuclXsc::GetElasticElementCrossSection(const G4ParticleDefinition* aParticle,
00117                                          G4double kinEnergy, 
00118                                          G4int Z, G4double A)
00119 {
00120   G4DynamicParticle* aDP = new G4DynamicParticle(aParticle,G4ParticleMomentum(1.,0.,0.), 
00121                                                 kinEnergy);
00122   fInelasticXsc = GetZandACrossSection(aDP, Z, G4int(A));
00123   delete aDP;
00124 
00125   return fElasticXsc;
00126 }
00127 
00129 
00130 G4double G4ComponentGGNuclNuclXsc::GetElasticIsotopeCrossSection(const G4ParticleDefinition* aParticle,
00131                                          G4double kinEnergy, 
00132                                          G4int Z, G4int A)
00133 {
00134   G4DynamicParticle* aDP = new G4DynamicParticle(aParticle,G4ParticleMomentum(1.,0.,0.), 
00135                                                 kinEnergy);
00136   fInelasticXsc = GetZandACrossSection(aDP, Z, A);
00137   delete aDP;
00138 
00139   return fElasticXsc;
00140 }
00141 
00143  
00144 G4double G4ComponentGGNuclNuclXsc::ComputeQuasiElasticRatio(const G4ParticleDefinition* aParticle,
00145                                          G4double kinEnergy, 
00146                                          G4int Z, G4int A)
00147 {
00148   G4DynamicParticle* aDP = new G4DynamicParticle(aParticle,G4ParticleMomentum(1.,0.,0.), 
00149                                                 kinEnergy);
00150   fInelasticXsc = GetZandACrossSection(aDP, Z, A);
00151   delete aDP;
00152   G4double ratio = 0.;
00153 
00154   if(fInelasticXsc > 0.)
00155   {
00156     ratio = (fInelasticXsc - fProductionXsc)/fInelasticXsc;
00157     if(ratio < 0.) ratio = 0.;
00158   }
00159   return ratio;
00160 }
00161  
00163 
00164 void
00165 G4ComponentGGNuclNuclXsc::CrossSectionDescription(std::ostream& outFile) const
00166 {
00167   outFile << "G4ComponentGGNuclNuclXsc calculates total, inelastic and\n"
00168           << "elastic cross sections for nucleus-nucleus collisions using\n"
00169           << "the Glauber model with Gribov corrections.  It is valid for\n"
00170           << "all incident energies above 100 keV./n";
00171 }
00172 
00174 
00175 G4bool 
00176 G4ComponentGGNuclNuclXsc::IsElementApplicable(const G4DynamicParticle* aDP, 
00177                                               G4int Z, const G4Material*)
00178 {
00179   G4bool applicable = false;
00180   G4double kineticEnergy = aDP->GetKineticEnergy();
00181 
00182   if (kineticEnergy >= fLowerLimit && Z > 1) applicable = true;
00183   return applicable;
00184 }
00185 
00187 //
00188 // Calculates total and inelastic Xsc, derives elastic as total - inelastic 
00189 // accordong to Glauber model with Gribov correction calculated in the dipole 
00190 // approximation on light cone. Gaussian density helps to calculate rest 
00191 // integrals of the model. [1] B.Z. Kopeliovich, nucl-th/0306044 
00192 
00193 
00194 G4double G4ComponentGGNuclNuclXsc::
00195 GetElementCrossSection(const G4DynamicParticle* aParticle, G4int Z,
00196                        const G4Material*)
00197 {
00198   G4int A = G4lrint(G4NistManager::Instance()->GetAtomicMassAmu(Z));
00199   return GetZandACrossSection(aParticle, Z, A);
00200 }
00201 
00203 //
00204 // Calculates total and inelastic Xsc, derives elastic as total - inelastic 
00205 // accordong to Glauber model with Gribov correction calculated in the dipole 
00206 // approximation on light cone. Gaussian density of point-like nucleons helps 
00207 // to calculate rest integrals of the model. [1] B.Z. Kopeliovich,
00208 // nucl-th/0306044 + simplification above
00209 
00210 
00211 G4double G4ComponentGGNuclNuclXsc::
00212 GetZandACrossSection(const G4DynamicParticle* aParticle,
00213                      G4int tZ, G4int tA)
00214 {
00215   G4double xsection;
00216   G4double sigma;
00217   G4double cofInelastic = 2.4;
00218   G4double cofTotal = 2.0;
00219   G4double nucleusSquare;
00220   G4double cB;
00221   G4double ratio;
00222 
00223   G4double pZ = aParticle->GetDefinition()->GetPDGCharge();
00224   G4double pA = aParticle->GetDefinition()->GetBaryonNumber();
00225 
00226   G4double pTkin = aParticle->GetKineticEnergy();  
00227   pTkin /= pA;
00228 
00229   G4double pN = pA - pZ;
00230   if( pN < 0. ) pN = 0.;
00231 
00232   G4double tN = tA - tZ;
00233   if( tN < 0. ) tN = 0.;
00234 
00235   G4double tR = GetNucleusRadius( G4double(tZ),G4double(tA) );  
00236   G4double pR = GetNucleusRadius(pZ,pA); 
00237 
00238   cB = GetCoulombBarier(aParticle, G4double(tZ), G4double(tA), pR, tR);
00239 
00240   if ( cB > 0. ) 
00241   {
00242     G4DynamicParticle* dProton = new G4DynamicParticle(theProton,
00243                                               G4ParticleMomentum(1.,0.,0.), 
00244                                               pTkin);
00245 
00246     G4DynamicParticle* dNeutron = new G4DynamicParticle(theNeutron,
00247                                               G4ParticleMomentum(1.,0.,0.), 
00248                                               pTkin);
00249 
00250     sigma = (pZ*tZ+pN*tN)*hnXsc->GetHadronNucleonXscNS(dProton, theProton);
00251 
00252     G4double ppInXsc = hnXsc->GetInelasticHadronNucleonXsc();
00253 
00254     sigma += (pZ*tN+pN*tZ)*hnXsc->GetHadronNucleonXscNS(dNeutron, theProton);
00255 
00256     G4double npInXsc = hnXsc->GetInelasticHadronNucleonXsc();
00257 
00258     // G4cout<<"ppInXsc = "<<ppInXsc/millibarn<<"; npInXsc = "<<npInXsc/millibarn<<G4endl;
00259     // G4cout<<"npTotXsc = "<<hnXsc->GetTotalHadronNucleonXsc()/millibarn<<"; npElXsc = "
00260     //                      <<hnXsc->GetElasticHadronNucleonXsc()/millibarn<<G4endl;
00261 
00262     nucleusSquare = cofTotal*pi*( pR*pR + tR*tR );   // basically 2piRR
00263 
00264     ratio      = sigma/nucleusSquare;
00265     xsection   = nucleusSquare*std::log( 1. + ratio );
00266     fTotalXsc  = xsection;
00267     fTotalXsc *= cB;
00268 
00269     fInelasticXsc = nucleusSquare*std::log( 1. + cofInelastic*ratio )/cofInelastic;
00270 
00271     fInelasticXsc *= cB;
00272     fElasticXsc   = fTotalXsc - fInelasticXsc;
00273 
00274     // if (fElasticXsc < DBL_MIN) fElasticXsc = DBL_MIN;
00275     /*    
00276     G4double difratio = ratio/(1.+ratio);
00277 
00278     fDiffractionXsc = 0.5*nucleusSquare*( difratio - std::log( 1. + difratio ) );
00279     */
00280     // production to be checked !!! edit MK xsc
00281 
00282     //sigma = (pZ*tZ+pN*tN)*GetHadronNucleonXscMK(theProton, pTkin, theProton) +
00283     //      (pZ*tN+pN*tZ)*GetHadronNucleonXscMK(theProton, pTkin, theNeutron);
00284 
00285     sigma = (pZ*tZ+pN*tN)*ppInXsc + (pZ*tN+pN*tZ)*npInXsc;
00286  
00287     ratio = sigma/nucleusSquare;
00288     fProductionXsc = nucleusSquare*std::log( 1. + cofInelastic*ratio )/cofInelastic;
00289 
00290     if (fElasticXsc < 0.) fElasticXsc = 0.;
00291   }
00292   else
00293   {
00294     fInelasticXsc  = 0.;
00295     fTotalXsc      = 0.;
00296     fElasticXsc    = 0.;
00297     fProductionXsc = 0.;
00298   }
00299   return fInelasticXsc;   // xsection; 
00300 }
00301 
00303 //
00304 //
00305 
00306 G4double G4ComponentGGNuclNuclXsc::
00307 GetCoulombBarier(const G4DynamicParticle* aParticle, G4double tZ, G4double tA,
00308                  G4double pR, G4double tR)
00309 {
00310   G4double ratio;
00311   G4double pZ = aParticle->GetDefinition()->GetPDGCharge();
00312 
00313   G4double pTkin = aParticle->GetKineticEnergy();
00314   // G4double pPlab = aParticle->GetTotalMomentum();
00315   G4double pM    = aParticle->GetDefinition()->GetPDGMass();
00316   // G4double tM    = tZ*proton_mass_c2 + (tA-tZ)*neutron_mass_c2; // ~ 1% accuracy
00317   G4double tM    = G4ParticleTable::GetParticleTable()->GetIonTable()->GetIonMass( G4int(tZ), G4int(tA) );
00318   G4double pElab = pTkin + pM;
00319   G4double totEcm  = std::sqrt(pM*pM + tM*tM + 2.*pElab*tM);
00320   // G4double pPcm  = pPlab*tM/totEcm;
00321   // G4double pTcm  = std::sqrt(pM*pM + pPcm*pPcm) - pM;
00322   G4double totTcm  = totEcm - pM -tM;
00323 
00324   G4double bC    = fine_structure_const*hbarc*pZ*tZ;
00325            bC   /= pR + tR;
00326            bC   /= 2.;  // 4., 2. parametrisation cof ??? vmg
00327 
00328            // G4cout<<"pTkin = "<<pTkin/GeV<<"; pPlab = "
00329            // <<pPlab/GeV<<"; bC = "<<bC/GeV<<"; pTcm = "<<pTcm/GeV<<G4endl;
00330 
00331   if( totTcm <= bC ) ratio = 0.;
00332   else             ratio = 1. - bC/totTcm;
00333 
00334   // if(ratio < DBL_MIN) ratio = DBL_MIN;
00335   if( ratio < 0.) ratio = 0.;
00336 
00337   // G4cout <<"ratio = "<<ratio<<G4endl;
00338   return ratio;
00339 }
00340 
00341 
00343 //
00344 // Return single-diffraction/inelastic cross-section ratio
00345 
00346 G4double G4ComponentGGNuclNuclXsc::
00347 GetRatioSD(const G4DynamicParticle* aParticle, G4double tA, G4double tZ)
00348 {
00349   G4double sigma, cofInelastic = 2.4, cofTotal = 2.0, nucleusSquare, ratio;
00350 
00351   G4double pZ = aParticle->GetDefinition()->GetPDGCharge();
00352   G4double pA = aParticle->GetDefinition()->GetBaryonNumber();
00353 
00354   G4double pTkin = aParticle->GetKineticEnergy();  
00355   pTkin /= pA;
00356 
00357   G4double pN = pA - pZ;
00358   if( pN < 0. ) pN = 0.;
00359 
00360   G4double tN = tA - tZ;
00361   if( tN < 0. ) tN = 0.;
00362 
00363   G4double tR = GetNucleusRadius(tZ,tA);  
00364   G4double pR = GetNucleusRadius(pZ,pA); 
00365 
00366   sigma = (pZ*tZ+pN*tN)*GetHadronNucleonXscNS(theProton, pTkin, theProton) +
00367           (pZ*tN+pN*tZ)*GetHadronNucleonXscNS(theProton, pTkin, theNeutron);
00368 
00369   nucleusSquare = cofTotal*pi*( pR*pR + tR*tR );   // basically 2piRR
00370   ratio = sigma/nucleusSquare;
00371   fInelasticXsc = nucleusSquare*std::log(1. + cofInelastic*ratio)/cofInelastic;
00372   G4double difratio = ratio/(1.+ratio);
00373 
00374   fDiffractionXsc = 0.5*nucleusSquare*( difratio - std::log( 1. + difratio ) );
00375 
00376   if (fInelasticXsc > 0.) ratio = fDiffractionXsc/fInelasticXsc;
00377   else                    ratio = 0.;
00378 
00379   return ratio; 
00380 }
00381 
00383 //
00384 // Return quasi-elastic/inelastic cross-section ratio
00385 
00386 G4double G4ComponentGGNuclNuclXsc::
00387 GetRatioQE(const G4DynamicParticle* aParticle, G4double tA, G4double tZ)
00388 {
00389   G4double sigma, cofInelastic = 2.4, cofTotal = 2.0, nucleusSquare, ratio;
00390 
00391   G4double pZ = aParticle->GetDefinition()->GetPDGCharge();
00392   G4double pA = aParticle->GetDefinition()->GetBaryonNumber();
00393 
00394   G4double pTkin = aParticle->GetKineticEnergy();  
00395   pTkin /= pA;
00396 
00397   G4double pN = pA - pZ;
00398   if( pN < 0. ) pN = 0.;
00399 
00400   G4double tN = tA - tZ;
00401   if( tN < 0. ) tN = 0.;
00402 
00403   G4double tR = GetNucleusRadius(tZ,tA);  
00404   G4double pR = GetNucleusRadius(pZ,pA); 
00405 
00406   sigma = (pZ*tZ+pN*tN)*GetHadronNucleonXscNS(theProton, pTkin, theProton) +
00407           (pZ*tN+pN*tZ)*GetHadronNucleonXscNS(theProton, pTkin, theNeutron);
00408 
00409   nucleusSquare = cofTotal*pi*( pR*pR + tR*tR );   // basically 2piRR
00410   ratio = sigma/nucleusSquare;
00411   fInelasticXsc = nucleusSquare*std::log(1. + cofInelastic*ratio)/cofInelastic;
00412 
00413   //  sigma = GetHNinelasticXsc(aParticle, tA, tZ);
00414   ratio = sigma/nucleusSquare;
00415   fProductionXsc = nucleusSquare*std::log(1. + cofInelastic*ratio)/cofInelastic;
00416 
00417   if (fInelasticXsc > fProductionXsc) ratio = (fInelasticXsc-fProductionXsc)/fInelasticXsc;
00418   else                                ratio = 0.;
00419   if ( ratio < 0. )                   ratio = 0.;
00420 
00421   return ratio; 
00422 }
00423 
00425 //
00426 // Returns hadron-nucleon Xsc according to differnt parametrisations:
00427 // [2] E. Levin, hep-ph/9710546
00428 // [3] U. Dersch, et al, hep-ex/9910052
00429 // [4] M.J. Longo, et al, Phys.Rev.Lett. 33 (1974) 725 
00430 
00431 G4double 
00432 G4ComponentGGNuclNuclXsc::GetHadronNucleonXsc(const G4DynamicParticle* aParticle, 
00433                                               const G4Element* anElement)
00434 {
00435   G4int At = G4lrint(anElement->GetN());  // number of nucleons 
00436   G4int Zt = G4lrint(anElement->GetZ());  // number of protons
00437   return GetHadronNucleonXsc(aParticle, At, Zt);
00438 }
00439 
00440 
00441 
00442 
00444 //
00445 // Returns hadron-nucleon Xsc according to differnt parametrisations:
00446 // [2] E. Levin, hep-ph/9710546
00447 // [3] U. Dersch, et al, hep-ex/9910052
00448 // [4] M.J. Longo, et al, Phys.Rev.Lett. 33 (1974) 725 
00449 
00450 G4double 
00451 G4ComponentGGNuclNuclXsc::GetHadronNucleonXsc(const G4DynamicParticle* aParticle, 
00452                                                    G4int At, G4int Zt)
00453 {
00454   G4double xsection = 0.;
00455 
00456   G4double targ_mass = G4ParticleTable::GetParticleTable()->
00457   GetIonTable()->GetIonMass(Zt, At);
00458   targ_mass = 0.939*GeV;  // ~mean neutron and proton ???
00459 
00460   G4double proj_mass = aParticle->GetMass();
00461   G4double proj_momentum = aParticle->GetMomentum().mag();
00462   G4double sMand = CalcMandelstamS ( proj_mass , targ_mass , proj_momentum );
00463 
00464   sMand /= GeV*GeV;  // in GeV for parametrisation
00465   proj_momentum /= GeV;
00466   const G4ParticleDefinition* pParticle = aParticle->GetDefinition();
00467 
00468   if(pParticle == theNeutron) // as proton ??? 
00469   {
00470     xsection = G4double(At)*(21.70*std::pow(sMand,0.0808) + 56.08*std::pow(sMand,-0.4525));
00471   } 
00472   else if(pParticle == theProton) 
00473   {
00474     xsection = G4double(At)*(21.70*std::pow(sMand,0.0808) + 56.08*std::pow(sMand,-0.4525));
00475   } 
00476  
00477   xsection *= millibarn;
00478   return xsection;
00479 }
00480 
00481 
00482 
00484 //
00485 // Returns hadron-nucleon Xsc according to PDG parametrisation (2005):
00486 // http://pdg.lbl.gov/2006/reviews/hadronicrpp.pdf
00487 //  At = number of nucleons,  Zt = number of protons 
00488 
00489 G4double 
00490 G4ComponentGGNuclNuclXsc::GetHadronNucleonXscPDG(G4ParticleDefinition* pParticle, 
00491                                                  G4double sMand, 
00492                                                  G4ParticleDefinition* tParticle)
00493 {
00494   G4double xsection = 0.;
00495   // G4bool pORn = (tParticle == theProton || nucleon == theNeutron  );  
00496   G4bool proton = (tParticle == theProton);
00497   G4bool neutron = (tParticle == theNeutron);
00498 
00499   // General PDG fit constants
00500 
00501   G4double s0   = 5.38*5.38; // in Gev^2
00502   G4double eta1 = 0.458;
00503   G4double eta2 = 0.458;
00504   G4double B    = 0.308;
00505 
00506   // const G4ParticleDefinition* pParticle = aParticle->GetDefinition();
00507   
00508   if(pParticle == theNeutron) // proton-neutron fit 
00509   {
00510     if ( proton )
00511     {
00512       xsection = ( 35.80 + B*std::pow(std::log(sMand/s0),2.) 
00513                   + 40.15*std::pow(sMand,-eta1) - 30.*std::pow(sMand,-eta2));
00514     }
00515     if ( neutron )
00516     {
00517       xsection = (35.45 + B*std::pow(std::log(sMand/s0),2.) 
00518              + 42.53*std::pow(sMand,-eta1) - 33.34*std::pow(sMand,-eta2)); // pp for nn
00519     }
00520   } 
00521   else if(pParticle == theProton) 
00522   {
00523     if ( proton )
00524     {
00525       xsection = (35.45 + B*std::pow(std::log(sMand/s0),2.) 
00526                 + 42.53*std::pow(sMand,-eta1) - 33.34*std::pow(sMand,-eta2));
00527 
00528     }
00529     if ( neutron )
00530     {
00531       xsection = (35.80 + B*std::pow(std::log(sMand/s0),2.) 
00532                   + 40.15*std::pow(sMand,-eta1) - 30.*std::pow(sMand,-eta2));
00533     }
00534   } 
00535   xsection *= millibarn; // parametrised in mb
00536   return xsection;
00537 }
00538 
00539 
00541 //
00542 // Returns nucleon-nucleon cross-section based on N. Starkov parametrisation of
00543 // data from mainly http://wwwppds.ihep.su:8001/c5-6A.html database
00544 // projectile nucleon is pParticle with pTkin shooting target nucleon tParticle
00545 
00546 G4double 
00547 G4ComponentGGNuclNuclXsc::GetHadronNucleonXscNS(G4ParticleDefinition* pParticle, 
00548                                                  G4double pTkin, 
00549                                                  G4ParticleDefinition* tParticle)
00550 {
00551   G4double xsection(0);
00552   // G4double Delta;   DHW 19 May 2011: variable set but not used
00553   G4double A0, B0;
00554   G4double hpXscv(0);
00555   G4double hnXscv(0);
00556 
00557   G4double targ_mass = tParticle->GetPDGMass();
00558   G4double proj_mass = pParticle->GetPDGMass(); 
00559 
00560   G4double proj_energy   = proj_mass + pTkin; 
00561   G4double proj_momentum = std::sqrt(pTkin*(pTkin+2*proj_mass));
00562 
00563   G4double sMand = CalcMandelstamS ( proj_mass , targ_mass , proj_momentum );
00564 
00565   sMand         /= GeV*GeV;  // in GeV for parametrisation
00566   proj_momentum /= GeV;
00567   proj_energy   /= GeV;
00568   proj_mass     /= GeV;
00569 
00570   // General PDG fit constants
00571 
00572   //  G4double s0   = 5.38*5.38; // in Gev^2
00573   //  G4double eta1 = 0.458;
00574   //  G4double eta2 = 0.458;
00575   //  G4double B    = 0.308;
00576   
00577   if( proj_momentum >= 373.)
00578   {
00579       return GetHadronNucleonXscPDG(pParticle,sMand,tParticle);
00580   }
00581   else if( proj_momentum >= 10. ) // high energy: pp = nn = np
00582     // if( proj_momentum >= 2.)
00583   {
00584     //  Delta = 1.;    // DHW 19 May 2011: variable set but not used
00585     //  if (proj_energy < 40.) Delta = 0.916+0.0021*proj_energy;
00586 
00587     if (proj_momentum >= 10.) {
00588       B0 = 7.5;
00589       A0 = 100. - B0*std::log(3.0e7);
00590 
00591       xsection = A0 + B0*std::log(proj_energy) - 11
00592                 + 103*std::pow(2*0.93827*proj_energy + proj_mass*proj_mass+
00593                   0.93827*0.93827,-0.165);        //  mb
00594     }
00595   }
00596   else // low energy pp = nn != np
00597   {
00598       if(pParticle == tParticle) // pp or nn      // nn to be pp
00599       {
00600         if( proj_momentum < 0.73 )
00601         {
00602           hnXscv = 23 + 50*( std::pow( std::log(0.73/proj_momentum), 3.5 ) );
00603         }
00604         else if( proj_momentum < 1.05  )
00605         {
00606           hnXscv = 23 + 40*(std::log(proj_momentum/0.73))*
00607                          (std::log(proj_momentum/0.73));
00608         }
00609         else  // if( proj_momentum < 10.  )
00610         {
00611           hnXscv = 39.0 + 
00612               75*(proj_momentum - 1.2)/(std::pow(proj_momentum,3.0) + 0.15);
00613         }
00614         xsection = hnXscv;
00615       }
00616       else  // pn to be np
00617       {
00618         if( proj_momentum < 0.8 )
00619         {
00620           hpXscv = 33+30*std::pow(std::log(proj_momentum/1.3),4.0);
00621         }      
00622         else if( proj_momentum < 1.4 )
00623         {
00624           hpXscv = 33+30*std::pow(std::log(proj_momentum/0.95),2.0);
00625         }
00626         else    // if( proj_momentum < 10.  )
00627         {
00628           hpXscv = 33.3+
00629               20.8*(std::pow(proj_momentum,2.0)-1.35)/
00630                  (std::pow(proj_momentum,2.50)+0.95);
00631         }
00632         xsection = hpXscv;
00633       }
00634   }
00635   xsection *= millibarn; // parametrised in mb
00636   return xsection;
00637 }
00638 
00640 //
00641 // Returns hadron-nucleon inelastic cross-section based on FTF-parametrisation 
00642 
00643 G4double 
00644 G4ComponentGGNuclNuclXsc::GetHNinelasticXscVU(const G4DynamicParticle* aParticle, 
00645                                               G4int At, G4int Zt)
00646 {
00647   G4int PDGcode = aParticle->GetDefinition()->GetPDGEncoding();
00648   G4int absPDGcode = std::abs(PDGcode);
00649   G4double Elab = aParticle->GetTotalEnergy();              
00650                           // (s - 2*0.88*GeV*GeV)/(2*0.939*GeV)/GeV;
00651   G4double Plab = aParticle->GetMomentum().mag();            
00652                           // std::sqrt(Elab * Elab - 0.88);
00653 
00654   Elab /= GeV;
00655   Plab /= GeV;
00656 
00657   G4double LogPlab    = std::log( Plab );
00658   G4double sqrLogPlab = LogPlab * LogPlab;
00659 
00660   //G4cout<<"Plab = "<<Plab<<G4endl;
00661 
00662   G4double NumberOfTargetProtons  = Zt; 
00663   G4double NumberOfTargetNucleons = At;
00664   G4double NumberOfTargetNeutrons = NumberOfTargetNucleons - NumberOfTargetProtons;
00665 
00666   if(NumberOfTargetNeutrons < 0.) NumberOfTargetNeutrons = 0.;
00667 
00668   G4double Xtotal = 0., Xelastic = 0., Xinelastic =0.;
00669 
00670   if( absPDGcode > 1000 )  //------Projectile is baryon --------
00671   {
00672        G4double XtotPP = 48.0 +  0. *std::pow(Plab, 0.  ) +
00673                          0.522*sqrLogPlab - 4.51*LogPlab;
00674 
00675        G4double XtotPN = 47.3 +  0. *std::pow(Plab, 0.  ) +
00676                          0.513*sqrLogPlab - 4.27*LogPlab;
00677 
00678        G4double XelPP  = 11.9 + 26.9*std::pow(Plab,-1.21) +
00679                          0.169*sqrLogPlab - 1.85*LogPlab;
00680 
00681        G4double XelPN  = 11.9 + 26.9*std::pow(Plab,-1.21) +
00682                          0.169*sqrLogPlab - 1.85*LogPlab;
00683 
00684        Xtotal          = ( NumberOfTargetProtons  * XtotPP +
00685                            NumberOfTargetNeutrons * XtotPN  );
00686 
00687        Xelastic        = ( NumberOfTargetProtons  * XelPP  +
00688                            NumberOfTargetNeutrons * XelPN   );
00689   }
00690 
00691   Xinelastic = Xtotal - Xelastic;
00692   if(Xinelastic < 0.) Xinelastic = 0.;
00693 
00694   return Xinelastic*= millibarn;
00695 }
00696 
00698 //
00699 //
00700 
00701 G4double 
00702 G4ComponentGGNuclNuclXsc::GetNucleusRadius(const G4DynamicParticle* , 
00703                                            const G4Element* anElement)
00704 {
00705   G4double At = anElement->GetN();
00706   G4double oneThird = 1.0/3.0;
00707   G4double cubicrAt = std::pow (At, oneThird); 
00708 
00709   G4double R;  // = fRadiusConst*cubicrAt;
00710   R = fRadiusConst*cubicrAt;
00711 
00712   G4double meanA  = 21.;
00713   G4double tauA1  = 40.; 
00714   G4double tauA2  = 10.; 
00715   G4double tauA3  = 5.; 
00716 
00717   G4double a1 = 0.85;
00718   G4double b1 = 1. - a1;
00719 
00720   G4double b2 = 0.3;
00721   G4double b3 = 4.;
00722 
00723   if (At > 20.)   // 20.
00724   {
00725     R *= ( a1 + b1*std::exp( -(At - meanA)/tauA1) ); 
00726   }
00727   else if (At > 3.5)
00728   {
00729     R *= ( 1.0 + b2*( 1. - std::exp( (At - meanA)/tauA2) ) ); 
00730   }
00731   else 
00732   {
00733     R *= ( 1.0 + b3*( 1. - std::exp( (At - meanA)/tauA3) ) ); 
00734   }
00735 
00736   return R;
00737 }
00738 
00740 //
00741 //
00742 
00743 G4double 
00744 G4ComponentGGNuclNuclXsc::GetNucleusRadius(G4double Zt, G4double At)
00745 {
00746   G4double R;
00747   R = GetNucleusRadiusDE(Zt,At);
00748   // R = GetNucleusRadiusRMS(Zt,At);
00749 
00750   return R;
00751 }
00752 
00754 
00755 G4double 
00756 G4ComponentGGNuclNuclXsc::GetNucleusRadiusGG(G4double At)
00757 {
00758   G4double oneThird = 1.0/3.0;
00759   G4double cubicrAt = std::pow (At, oneThird); 
00760 
00761   G4double R;  // = fRadiusConst*cubicrAt;  
00762   R = fRadiusConst*cubicrAt;
00763 
00764   G4double meanA = 20.;
00765   G4double tauA  = 20.;
00766 
00767   if ( At > 20.)   // 20.
00768   {
00769     R *= ( 0.8 + 0.2*std::exp( -(At - meanA)/tauA) ); 
00770   }
00771   else
00772   {
00773     R *= ( 1.0 + 0.1*( 1. - std::exp( (At - meanA)/tauA) ) ); 
00774   }
00775 
00776   return R;
00777 }
00778 
00780 //
00781 //
00782 
00783 G4double 
00784 G4ComponentGGNuclNuclXsc::GetNucleusRadiusDE(G4double Z, G4double A)
00785 {
00786   // algorithm from diffuse-elastic
00787 
00788   G4double R, r0, a11, a12, a13, a2, a3;
00789 
00790   a11 = 1.26;  // 1.08, 1.16
00791   a12 = 1.;  // 1.08, 1.16
00792   a13 = 1.12;  // 1.08, 1.16
00793   a2 = 1.1;
00794   a3 = 1.;
00795 
00796   // Special rms radii for light nucleii
00797 
00798   if (A < 50.)
00799   {
00800     if     (std::abs(A-1.) < 0.5)                         return 0.89*fermi; // p
00801     else if(std::abs(A-2.) < 0.5)                         return 2.13*fermi; // d
00802     else if(std::abs(Z-1.) < 0.5 && std::abs(A-3.) < 0.5) return 1.80*fermi; // t
00803 
00804     else if(std::abs(Z-2.) < 0.5 && std::abs(A-3.) < 0.5) return 1.96*fermi; // He3
00805     else if(std::abs(Z-2.) < 0.5 && std::abs(A-4.) < 0.5) return 1.68*fermi; // He4
00806 
00807     else if(std::abs(Z-3.) < 0.5)                         return 2.40*fermi; // Li7
00808     else if(std::abs(Z-4.) < 0.5)                         return 2.51*fermi; // Be9
00809 
00810     else if( 10.  < A && A <= 16. ) r0  = a11*( 1 - std::pow(A, -2./3.) )*fermi;   // 1.08*fermi;
00811     else if( 15.  < A && A <= 20. ) r0  = a12*( 1 - std::pow(A, -2./3.) )*fermi;
00812     else if( 20.  < A && A <= 30. ) r0  = a13*( 1 - std::pow(A, -2./3.) )*fermi;
00813     else                            r0  = a2*fermi;
00814 
00815     R = r0*std::pow( A, 1./3. );
00816   }
00817   else
00818   {
00819     r0 = a3*fermi;
00820 
00821     R  = r0*std::pow(A, 0.27);
00822   }
00823   return R;
00824 }
00825 
00826 
00828 //
00829 // RMS radii from e-A scattering data
00830 
00831 G4double 
00832 G4ComponentGGNuclNuclXsc::GetNucleusRadiusRMS(G4double Z, G4double A)
00833 {
00834 
00835   if     (std::abs(A-1.) < 0.5)                         return 0.89*fermi; // p
00836   else if(std::abs(A-2.) < 0.5)                         return 2.13*fermi; // d
00837   else if(std::abs(Z-1.) < 0.5 && std::abs(A-3.) < 0.5) return 1.80*fermi; // t
00838 
00839   else if(std::abs(Z-2.) < 0.5 && std::abs(A-3.) < 0.5) return 1.96*fermi; // He3
00840   else if(std::abs(Z-2.) < 0.5 && std::abs(A-4.) < 0.5) return 1.68*fermi; // He4
00841 
00842   else if(std::abs(Z-3.) < 0.5)                         return 2.40*fermi; // Li7
00843   else if(std::abs(Z-4.) < 0.5)                         return 2.51*fermi; // Be9
00844 
00845   else                               return 1.24*std::pow(A, 0.28 )*fermi; // A > 9
00846 }
00847 
00848 
00850 //
00851 //
00852 
00853 G4double G4ComponentGGNuclNuclXsc::CalculateEcmValue(const G4double mp, 
00854                                                      const G4double mt, 
00855                                                      const G4double Plab)
00856 {
00857   G4double Elab = std::sqrt ( mp * mp + Plab * Plab );
00858   G4double Ecm  = std::sqrt ( mp * mp + mt * mt + 2 * Elab * mt );
00859   // G4double Pcm  = Plab * mt / Ecm;
00860   // G4double KEcm = std::sqrt ( Pcm * Pcm + mp * mp ) - mp;
00861 
00862   return Ecm ; // KEcm;
00863 }
00864 
00865 
00867 //
00868 //
00869 
00870 G4double G4ComponentGGNuclNuclXsc::CalcMandelstamS(const G4double mp, 
00871                                                    const G4double mt, 
00872                                                    const G4double Plab)
00873 {
00874   G4double Elab = std::sqrt ( mp * mp + Plab * Plab );
00875   G4double sMand  = mp*mp + mt*mt + 2*Elab*mt ;
00876 
00877   return sMand;
00878 }
00879 
00880 //
00881 //

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