Gabriele Cosmo
130 lines
4.1 KiB
C++
130 lines
4.1 KiB
C++
//
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// ********************************************************************
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// * License and Disclaimer *
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// * *
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// * The Geant4 software is copyright of the Copyright Holders of *
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// * the Geant4 Collaboration. It is provided under the terms and *
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// * conditions of the Geant4 Software License, included in the file *
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// * LICENSE and available at http://cern.ch/geant4/license . These *
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// * include a list of copyright holders. *
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// * *
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// * Neither the authors of this software system, nor their employing *
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// * institutes,nor the agencies providing financial support for this *
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// * work make any representation or warranty, express or implied, *
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// * regarding this software system or assume any liability for its *
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// * use. Please see the license in the file LICENSE and URL above *
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// * for the full disclaimer and the limitation of liability. *
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// * *
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// * This code implementation is the result of the scientific and *
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// * technical work of the GEANT4 collaboration. *
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// * By using, copying, modifying or distributing the software (or *
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// * any work based on the software) you agree to acknowledge its *
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// * use in resulting scientific publications, and indicate your *
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// * acceptance of all terms of the Geant4 Software license. *
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// ********************************************************************
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//
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// Neutron-electron elastic cross section base on the integration of
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// the Rosenbluth differential xsc
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//
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// 16.05.17 V. Grichine
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//
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//
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#ifndef G4NeutronElectronElXsc_h
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#define G4NeutronElectronElXsc_h
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#include "globals.hh"
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#include "G4VCrossSectionDataSet.hh"
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#include "G4DynamicParticle.hh"
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// class G4ParticleDefinition;
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class G4PhysicsLogVector;
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class G4PhysicsTable;
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class G4NeutronElectronElXsc : public G4VCrossSectionDataSet
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{
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public:
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G4NeutronElectronElXsc();
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~G4NeutronElectronElXsc();
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void Initialise();
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virtual
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G4bool IsElementApplicable(const G4DynamicParticle*, G4int Z, const G4Material*);
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virtual
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G4double GetElementCrossSection(const G4DynamicParticle*,
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G4int Z, const G4Material*);
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G4double GetRosenbluthXsc(const G4DynamicParticle*,
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G4int Z, const G4Material*);
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G4double XscIntegrand(G4double x);
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G4double GetElementNonRelXsc(const G4DynamicParticle*,
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G4int Z, const G4Material*);
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G4double CalculateAm( G4double momentum);
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inline G4double GetAm(){return fAm;};
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void SetCutEnergy(G4double ec){fCutEnergy=ec;};
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G4double GetCutEnergy(){return fCutEnergy;};
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void SetBiasingFactor(G4double bf){fBiasingFactor=bf;};
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protected:
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G4double fM, fM2, fMv2, fme, fme2, fee, fee2;
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G4double fCofXsc; //
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G4double fAm; //
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G4int fEnergyBin;
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G4double fMinEnergy, fMaxEnergy, fCutEnergy; // minimal recoil electron energy detected
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G4double fBiasingFactor; // biasing xsc up
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G4PhysicsLogVector* fEnergyXscVector;
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static const G4double fXscArray[200];
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};
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////////////////////////////////////////////////////////////////////
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//
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// return Wentzel atom screening correction for neutron-electron scattering
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inline G4double G4NeutronElectronElXsc::CalculateAm( G4double momentum)
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{
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G4double k = momentum/CLHEP::hbarc;
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G4double ch = 1.13;
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G4double zn = 1.77*k*CLHEP::Bohr_radius;
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G4double zn2 = zn*zn;
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fAm = ch/zn2;
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return fAm;
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}
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////////////////////////////////////////////////////
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//
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// Slow electron (Tkin << me_c2) in the neutron rest frame
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inline G4double G4NeutronElectronElXsc::
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GetElementNonRelXsc(const G4DynamicParticle* aPart, G4int ZZ,
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const G4Material*)
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{
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G4double result(0.), te(0.), momentum(0.);
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te = aPart->GetKineticEnergy()*fme/fM;
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momentum = std::sqrt( te*(te + 2.*fme) );
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fAm = CalculateAm(momentum);
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result = 1. + std::log(1. +1./fAm);
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result *= fCofXsc; //*energy;
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result *= ZZ; // incoherent sum over all element electrons
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return result;
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}
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#endif
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