G4NuclearStopping.cc

Go to the documentation of this file.

//
// ********************************************************************
// * 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: G4NuclearStopping.cc 105121 2017-07-13 13:38:25Z gcosmo $
//
// -----------------------------------------------------------------------------
//
// GEANT4 Class file
//
// File name:     G4NuclearStopping
//
// Author:        Vladimir Ivanchenko
//
// Creation date: 20 July 2009
// 
// Modified:
//
// Warning: this class should be instantiated after G4ionIonisation
//
// -----------------------------------------------------------------------------
//
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......

#include "G4NuclearStopping.hh"
#include "G4ICRU49NuclearStoppingModel.hh"
#include "G4SystemOfUnits.hh"
#include "G4PhysicalConstants.hh"

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......

using namespace std;

G4NuclearStopping::G4NuclearStopping(const G4String& processName)
  : G4VEmProcess(processName)
{
  isInitialized = false;  
  SetProcessSubType(fNuclearStopping);
  SetBuildTableFlag(false);
  enableAlongStepDoIt = true; 
  enablePostStepDoIt = false; 
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......

G4NuclearStopping::~G4NuclearStopping()
{}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......

G4bool G4NuclearStopping::IsApplicable (const G4ParticleDefinition& p)
{
  return (p.GetPDGCharge() != 0.0 && !p.IsShortLived());
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......

void G4NuclearStopping::InitialiseProcess(const G4ParticleDefinition*)
{
  if(!isInitialized) {
    isInitialized = true;

    if(!EmModel(1)) {
      SetEmModel(new G4ICRU49NuclearStoppingModel());
    }
    AddEmModel(1, EmModel());
    EmModel()->SetParticleChange(&nParticleChange);
  }
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......

G4double 
G4NuclearStopping::AlongStepGetPhysicalInteractionLength(
     const G4Track&, G4double, G4double, G4double&, G4GPILSelection* selection)
{
  *selection = NotCandidateForSelection;
  return DBL_MAX;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......

G4VParticleChange* G4NuclearStopping::AlongStepDoIt(const G4Track& track,
                            const G4Step&  step)
{
  nParticleChange.InitializeForAlongStep(track);

  // this line only valid if nuclear stopping 
  // is computed after G4ionIonisation process 
  nParticleChange.SetProposedCharge(step.GetPostStepPoint()->GetCharge());

  G4double T2 = step.GetPostStepPoint()->GetKineticEnergy();

  const G4ParticleDefinition* part = track.GetParticleDefinition();
  G4double Z = std::abs(part->GetPDGCharge()/eplus);

  if(T2 > 0.0 && T2*proton_mass_c2 < Z*Z*MeV*part->GetPDGMass()) {

    G4double length = step.GetStepLength(); 
    if(length > 0.0) {

      // primary
      G4double T1= step.GetPreStepPoint()->GetKineticEnergy();
      G4double T = 0.5*(T1 + T2);
      const G4MaterialCutsCouple* couple = track.GetMaterialCutsCouple(); 
      G4VEmModel* mod = SelectModel(T, couple->GetIndex());

      // sample stopping
      G4double nloss = 
    length*mod->ComputeDEDXPerVolume(couple->GetMaterial(), part, T);
      if(nloss > T1) { nloss = T1; }
      nParticleChange.SetProposedKineticEnergy(T1 - nloss);
      nParticleChange.ProposeLocalEnergyDeposit(nloss);
      nParticleChange.ProposeNonIonizingEnergyDeposit(nloss);
    }
  }
  return &nParticleChange;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......

void G4NuclearStopping::PrintInfo()
{}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......