Gabriele Cosmo
69 lines
2.5 KiB
C++
69 lines
2.5 KiB
C++
//
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// ********************************************************************
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// * DISCLAIMER *
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// * *
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// * The following disclaimer summarizes all the specific disclaimers *
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// * of contributors to this software. The specific disclaimers,which *
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// * govern, are listed with their locations in: *
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// * http://cern.ch/geant4/license *
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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. *
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// * *
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// * This code implementation is the intellectual property of the *
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// * GEANT4 collaboration. *
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// * By copying, distributing or modifying the Program (or any work *
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// * based on the Program) you indicate your acceptance of this *
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// * statement, and all its terms. *
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// ********************************************************************
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//
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//
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//
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#ifndef G4NuclearFermiDensity_h
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#define G4NuclearFermiDensity_h 1
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#include "globals.hh"
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#include "G4ThreeVector.hh"
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#include "G4VNuclearDensity.hh"
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#include <CLHEP/Units/PhysicalConstants.h> // pi, fermi,..
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#include <math.h> // pow
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class G4NuclearFermiDensity : public G4VNuclearDensity
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{
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public:
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G4NuclearFermiDensity(G4double anA, G4double aZ);
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~G4NuclearFermiDensity();
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G4double GetRelativeDensity(const G4ThreeVector & aPosition) const
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{
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return 1./(1.+exp((aPosition.mag()-theR)/a));
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}
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G4double GetRadius(const G4double maxRelativeDenisty) const
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{
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return (maxRelativeDenisty>0 && maxRelativeDenisty <= 1 ) ?
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(theR + a*log((1-maxRelativeDenisty+exp(-1*theR/a))/maxRelativeDenisty)) : DBL_MAX;
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}
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G4double GetDeriv(const G4ThreeVector & aPosition) const
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{
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return -exp((aPosition.mag()-theR)/a) * sqr(GetDensity(aPosition)) / (a*Getrho0());
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}
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private:
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G4int theA;
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G4int theZ;
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G4double theR; // Nuclear Radius
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const G4double a; // Determines the nuclear surface thickness
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};
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#endif
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