Gabriele Cosmo
85 lines
3.4 KiB
C++
85 lines
3.4 KiB
C++
//
|
|
// ********************************************************************
|
|
// * 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. *
|
|
// ********************************************************************
|
|
//
|
|
//
|
|
// -------------------------------------------------------------------
|
|
// GEANT 4 class implementation file
|
|
//
|
|
// CERN, Geneva, Switzerland
|
|
//
|
|
// File name: G4SigmaMinusField.cc
|
|
//
|
|
// Author: Alessandro Brunengo (Alessandro.Brunengo@ge.infn.it)
|
|
//
|
|
// Creation date: 5 June 2000
|
|
// -------------------------------------------------------------------
|
|
|
|
#include "G4SigmaMinusField.hh"
|
|
#include "G4PhysicalConstants.hh"
|
|
#include "G4SystemOfUnits.hh"
|
|
#include "G4NucleiProperties.hh"
|
|
#include "G4VNuclearDensity.hh"
|
|
#include "G4FermiMomentum.hh"
|
|
#include "G4SigmaMinus.hh"
|
|
#include "G4HadTmpUtil.hh"
|
|
#include "G4Pow.hh"
|
|
|
|
G4SigmaMinusField::G4SigmaMinusField(G4V3DNucleus * nucleus, G4double coeff)
|
|
: G4VNuclearField(nucleus)
|
|
{
|
|
theCoeff = coeff;
|
|
}
|
|
|
|
G4SigmaMinusField::~G4SigmaMinusField()
|
|
{ }
|
|
|
|
G4double G4SigmaMinusField::GetField(const G4ThreeVector & aPosition)
|
|
{
|
|
// Field is 0 out of the nucleus!
|
|
if(aPosition.mag() >= radius) return 0.0;
|
|
|
|
G4double sigmaMinusMass = G4SigmaMinus::SigmaMinus()->GetPDGMass();
|
|
|
|
G4int A = theNucleus->GetMassNumber();
|
|
G4int Z = theNucleus->GetCharge();
|
|
G4double bindingEnergy = G4NucleiProperties::GetBindingEnergy(A, Z);
|
|
G4double nucleusMass = Z*proton_mass_c2+(A-Z)*neutron_mass_c2+bindingEnergy;
|
|
G4double reducedMass = sigmaMinusMass*nucleusMass/(sigmaMinusMass+nucleusMass);
|
|
|
|
const G4VNuclearDensity * nuclearDensity=theNucleus->GetNuclearDensity();
|
|
G4double density = nuclearDensity->GetDensity(aPosition);
|
|
|
|
return -2.*pi*hbarc*hbarc/reducedMass*(2.0)*theCoeff*density+GetBarrier();
|
|
}
|
|
|
|
G4double G4SigmaMinusField::GetBarrier()
|
|
{
|
|
G4double A = theNucleus->GetMassNumber();
|
|
G4double Z = theNucleus->GetCharge();
|
|
G4double coulombBarrier = (1.44/1.14) * MeV * Z / (1.0 + G4Pow::GetInstance()->A13(A));
|
|
return -coulombBarrier;
|
|
}
|
|
|