// // ******************************************************************** // * License and Disclaimer * // * * // * The Geant4 software is copyright of the Copyright Holders of * // * the Geant4 Collaboration. It is provided under the terms and * // * conditions of the Geant4 Software License, included in the file * // * LICENSE and available at http://cern.ch/geant4/license . These * // * include a list of copyright holders. * // * * // * Neither the authors of this software system, nor their employing * // * institutes,nor the agencies providing financial support for this * // * work make any representation or warranty, express or implied, * // * regarding this software system or assume any liability for its * // * use. Please see the license in the file LICENSE and URL above * // * for the full disclaimer and the limitation of liability. * // * * // * This code implementation is the result of the scientific and * // * technical work of the GEANT4 collaboration. * // * By using, copying, modifying or distributing the software (or * // * any work based on the software) you agree to acknowledge its * // * use in resulting scientific publications, and indicate your * // * acceptance of all terms of the Geant4 Software license. * // ******************************************************************** // // // $Id: G4DiffuseElastic.hh,v 1.17 2009/09/22 16:21:46 vnivanch Exp $ // GEANT4 tag $Name: geant4-09-03-ref-09 $ // // // G4 Model: optical elastic scattering with 4-momentum balance // // Class Description // Final state production model for hadron nuclear elastic scattering; // Class Description - End // // // 24.05.07 V. Grichine first implementation for hadron (no Coulomb) elastic scattering // 04.09.07 V. Grichine implementation for Coulomb elastic scattering #ifndef G4DiffuseElastic_h #define G4DiffuseElastic_h 1 #include "globals.hh" #include "G4HadronicInteraction.hh" #include "G4HadProjectile.hh" #include "G4Nucleus.hh" using namespace std; class G4ParticleDefinition; class G4PhysicsTable; class G4PhysicsLogVector; class G4DiffuseElastic : public G4HadronicInteraction { public: G4DiffuseElastic(); G4DiffuseElastic(const G4ParticleDefinition* aParticle); virtual ~G4DiffuseElastic(); void Initialise(); void InitialiseOnFly(G4double Z, G4double A); void BuildAngleTable(); G4HadFinalState * ApplyYourself(const G4HadProjectile & aTrack, G4Nucleus & targetNucleus); void SetPlabLowLimit(G4double value); void SetHEModelLowLimit(G4double value); void SetQModelLowLimit(G4double value); void SetLowestEnergyLimit(G4double value); void SetRecoilKinEnergyLimit(G4double value); G4double SampleT(const G4ParticleDefinition* aParticle, G4double p, G4double A); G4double SampleTableT(const G4ParticleDefinition* aParticle, G4double p, G4double Z, G4double A); G4double SampleThetaCMS(const G4ParticleDefinition* aParticle, G4double p, G4double A); G4double SampleTableThetaCMS(const G4ParticleDefinition* aParticle, G4double p, G4double Z, G4double A); G4double GetScatteringAngle(G4int iMomentum, G4int iAngle, G4double position); G4double SampleThetaLab(const G4HadProjectile* aParticle, G4double tmass, G4double A); G4double GetDiffuseElasticXsc( const G4ParticleDefinition* particle, G4double theta, G4double momentum, G4double A ); G4double GetInvElasticXsc( const G4ParticleDefinition* particle, G4double theta, G4double momentum, G4double A, G4double Z ); G4double GetDiffuseElasticSumXsc( const G4ParticleDefinition* particle, G4double theta, G4double momentum, G4double A, G4double Z ); G4double GetInvElasticSumXsc( const G4ParticleDefinition* particle, G4double tMand, G4double momentum, G4double A, G4double Z ); G4double IntegralElasticProb( const G4ParticleDefinition* particle, G4double theta, G4double momentum, G4double A ); G4double GetCoulombElasticXsc( const G4ParticleDefinition* particle, G4double theta, G4double momentum, G4double Z ); G4double GetInvCoulombElasticXsc( const G4ParticleDefinition* particle, G4double tMand, G4double momentum, G4double A, G4double Z ); G4double GetCoulombTotalXsc( const G4ParticleDefinition* particle, G4double momentum, G4double Z ); G4double GetCoulombIntegralXsc( const G4ParticleDefinition* particle, G4double momentum, G4double Z, G4double theta1, G4double theta2 ); G4double CalculateParticleBeta( const G4ParticleDefinition* particle, G4double momentum ); G4double CalculateZommerfeld( G4double beta, G4double Z1, G4double Z2 ); G4double CalculateAm( G4double momentum, G4double n, G4double Z); G4double CalculateNuclearRad( G4double A); G4double ThetaCMStoThetaLab(const G4DynamicParticle* aParticle, G4double tmass, G4double thetaCMS); G4double ThetaLabToThetaCMS(const G4DynamicParticle* aParticle, G4double tmass, G4double thetaLab); void TestAngleTable(const G4ParticleDefinition* theParticle, G4double partMom, G4double Z, G4double A); G4double BesselJzero(G4double z); G4double BesselJone(G4double z); G4double DampFactor(G4double z); G4double BesselOneByArg(G4double z); G4double GetDiffElasticProb(G4double theta); G4double GetDiffElasticSumProb(G4double theta); G4double GetDiffElasticSumProbA(G4double alpha); G4double GetIntegrandFunction(G4double theta); G4double GetNuclearRadius(){return fNuclearRadius;}; private: G4ParticleDefinition* theProton; G4ParticleDefinition* theNeutron; G4ParticleDefinition* theDeuteron; G4ParticleDefinition* theAlpha; const G4ParticleDefinition* thePionPlus; const G4ParticleDefinition* thePionMinus; G4double lowEnergyRecoilLimit; G4double lowEnergyLimitHE; G4double lowEnergyLimitQ; G4double lowestEnergyLimit; G4double plabLowLimit; G4int fEnergyBin; G4int fAngleBin; G4PhysicsLogVector* fEnergyVector; G4PhysicsTable* fAngleTable; std::vector fAngleBank; std::vector fElementNumberVector; std::vector fElementNameVector; const G4ParticleDefinition* fParticle; G4double fWaveVector; G4double fAtomicWeight; G4double fAtomicNumber; G4double fNuclearRadius; G4double fBeta; G4double fZommerfeld; G4double fAm; G4bool fAddCoulomb; }; inline void G4DiffuseElastic::SetRecoilKinEnergyLimit(G4double value) { lowEnergyRecoilLimit = value; } inline void G4DiffuseElastic::SetPlabLowLimit(G4double value) { plabLowLimit = value; } inline void G4DiffuseElastic::SetHEModelLowLimit(G4double value) { lowEnergyLimitHE = value; } inline void G4DiffuseElastic::SetQModelLowLimit(G4double value) { lowEnergyLimitQ = value; } inline void G4DiffuseElastic::SetLowestEnergyLimit(G4double value) { lowestEnergyLimit = value; } ///////////////////////////////////////////////////////////// // // Bessel J0 function based on rational approximation from // J.F. Hart, Computer Approximations, New York, Willey 1968, p. 141 inline G4double G4DiffuseElastic::BesselJzero(G4double value) { G4double modvalue, value2, fact1, fact2, arg, shift, bessel; modvalue = fabs(value); if ( value < 8.0 && value > -8.0 ) { value2 = value*value; fact1 = 57568490574.0 + value2*(-13362590354.0 + value2*( 651619640.7 + value2*(-11214424.18 + value2*( 77392.33017 + value2*(-184.9052456 ) ) ) ) ); fact2 = 57568490411.0 + value2*( 1029532985.0 + value2*( 9494680.718 + value2*(59272.64853 + value2*(267.8532712 + value2*1.0 ) ) ) ); bessel = fact1/fact2; } else { arg = 8.0/modvalue; value2 = arg*arg; shift = modvalue-0.785398164; fact1 = 1.0 + value2*(-0.1098628627e-2 + value2*(0.2734510407e-4 + value2*(-0.2073370639e-5 + value2*0.2093887211e-6 ) ) ); fact2 = -0.1562499995e-1 + value2*(0.1430488765e-3 + value2*(-0.6911147651e-5 + value2*(0.7621095161e-6 - value2*0.934945152e-7 ) ) ); bessel = sqrt(0.636619772/modvalue)*(cos(shift)*fact1 - arg*sin(shift)*fact2 ); } return bessel; } ///////////////////////////////////////////////////////////// // // Bessel J1 function based on rational approximation from // J.F. Hart, Computer Approximations, New York, Willey 1968, p. 141 inline G4double G4DiffuseElastic::BesselJone(G4double value) { G4double modvalue, value2, fact1, fact2, arg, shift, bessel; modvalue = fabs(value); if ( modvalue < 8.0 ) { value2 = value*value; fact1 = value*(72362614232.0 + value2*(-7895059235.0 + value2*( 242396853.1 + value2*(-2972611.439 + value2*( 15704.48260 + value2*(-30.16036606 ) ) ) ) ) ); fact2 = 144725228442.0 + value2*(2300535178.0 + value2*(18583304.74 + value2*(99447.43394 + value2*(376.9991397 + value2*1.0 ) ) ) ); bessel = fact1/fact2; } else { arg = 8.0/modvalue; value2 = arg*arg; shift = modvalue - 2.356194491; fact1 = 1.0 + value2*( 0.183105e-2 + value2*(-0.3516396496e-4 + value2*(0.2457520174e-5 + value2*(-0.240337019e-6 ) ) ) ); fact2 = 0.04687499995 + value2*(-0.2002690873e-3 + value2*( 0.8449199096e-5 + value2*(-0.88228987e-6 + value2*0.105787412e-6 ) ) ); bessel = sqrt( 0.636619772/modvalue)*(cos(shift)*fact1 - arg*sin(shift)*fact2); if (value < 0.0) bessel = -bessel; } return bessel; } //////////////////////////////////////////////////////////////////// // // damp factor in diffraction x/sh(x), x was already *pi inline G4double G4DiffuseElastic::DampFactor(G4double x) { G4double df; G4double f2 = 2., f3 = 6., f4 = 24.; // first factorials // x *= pi; if( std::fabs(x) < 0.01 ) { df = 1./(1. + x/f2 + x*x/f3 + x*x*x/f4); } else { df = x/std::sinh(x); } return df; } //////////////////////////////////////////////////////////////////// // // return J1(x)/x with special case for small x inline G4double G4DiffuseElastic::BesselOneByArg(G4double x) { G4double x2, result; if( std::fabs(x) < 0.01 ) { x *= 0.5; x2 = x*x; result = 2. - x2 + x2*x2/6.; } else { result = BesselJone(x)/x; } return result; } //////////////////////////////////////////////////////////////////// // // return particle beta inline G4double G4DiffuseElastic::CalculateParticleBeta( const G4ParticleDefinition* particle, G4double momentum ) { G4double mass = particle->GetPDGMass(); G4double a = momentum/mass; fBeta = a/std::sqrt(1+a*a); return fBeta; } //////////////////////////////////////////////////////////////////// // // return Zommerfeld parameter for Coulomb scattering inline G4double G4DiffuseElastic::CalculateZommerfeld( G4double beta, G4double Z1, G4double Z2 ) { fZommerfeld = fine_structure_const*Z1*Z2/beta; return fZommerfeld; } //////////////////////////////////////////////////////////////////// // // return Wentzel correction for Coulomb scattering inline G4double G4DiffuseElastic::CalculateAm( G4double momentum, G4double n, G4double Z) { G4double k = momentum/hbarc; G4double ch = 1.13 + 3.76*n*n; G4double zn = 1.77*k*std::pow(Z,-1./3.)*Bohr_radius; G4double zn2 = zn*zn; fAm = ch/zn2; return fAm; } //////////////////////////////////////////////////////////////////// // // calculate nuclear radius for different atomic weights using different approximations inline G4double G4DiffuseElastic::CalculateNuclearRad( G4double A) { G4double r0; if( A < 50. ) { if( A > 10. ) r0 = 1.16*( 1 - std::pow(A, -2./3.) )*fermi; // 1.08*fermi; else r0 = 1.1*fermi; fNuclearRadius = r0*std::pow(A, 1./3.); } else { r0 = 1.7*fermi; // 1.7*fermi; fNuclearRadius = r0*std::pow(A, 0.27); // 0.27); } return fNuclearRadius; } //////////////////////////////////////////////////////////////////// // // return Coulomb scattering differential xsc with Wentzel correction inline G4double G4DiffuseElastic::GetCoulombElasticXsc( const G4ParticleDefinition* particle, G4double theta, G4double momentum, G4double Z ) { G4double sinHalfTheta = std::sin(0.5*theta); G4double sinHalfTheta2 = sinHalfTheta*sinHalfTheta; G4double beta = CalculateParticleBeta( particle, momentum); G4double z = particle->GetPDGCharge(); G4double n = CalculateZommerfeld( beta, z, Z ); G4double am = CalculateAm( momentum, n, Z); G4double k = momentum/hbarc; G4double ch = 0.5*n/k; G4double ch2 = ch*ch; G4double xsc = ch2/(sinHalfTheta2+am)/(sinHalfTheta2+am); return xsc; } //////////////////////////////////////////////////////////////////// // // return Coulomb scattering total xsc with Wentzel correction inline G4double G4DiffuseElastic::GetCoulombTotalXsc( const G4ParticleDefinition* particle, G4double momentum, G4double Z ) { G4double beta = CalculateParticleBeta( particle, momentum); G4cout<<"beta = "<GetPDGCharge(); G4double n = CalculateZommerfeld( beta, z, Z ); G4cout<<"fZomerfeld = "<