G4UAtomicDeexcitation.cc

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// $Id: G4UAtomicDeexcitation.cc,v 1.11 
//
// -------------------------------------------------------------------
//
// Geant4 Class file
//  
// Authors: Alfonso Mantero (Alfonso.Mantero@ge.infn.it)
//
// Created 22 April 2010 from old G4UAtomicDeexcitation class 
//
// Modified:
// ---------
// 20 Oct 2011  Alf  modified to take into account ECPSSR form Form Factor
// 03 Nov 2011  Alf  Extended Empirical and Form Factor ionisation XS models
//                   out thei ranges with Analytical one.
// 07 Nov 2011  Alf  Restored original ioniation XS for alphas, 
//                   letting scaled ones for other ions.   
// 20 Mar 2012  LP   Register G4PenelopeIonisationCrossSection
//
// -------------------------------------------------------------------
//
// Class description:
// Implementation of atomic deexcitation 
//
// -------------------------------------------------------------------

#include "G4UAtomicDeexcitation.hh"
#include "G4PhysicalConstants.hh"
#include "G4SystemOfUnits.hh"
#include "Randomize.hh"
#include "G4Gamma.hh"
#include "G4AtomicTransitionManager.hh"
#include "G4FluoTransition.hh"
#include "G4Electron.hh"
#include "G4Positron.hh"
#include "G4Proton.hh"
#include "G4Alpha.hh"

#include "G4teoCrossSection.hh"
#include "G4empCrossSection.hh"
#include "G4PenelopeIonisationCrossSection.hh"
#include "G4LivermoreIonisationCrossSection.hh"
#include "G4EmCorrections.hh"
#include "G4LossTableManager.hh"
#include "G4Material.hh"
#include "G4AtomicShells.hh"

using namespace std;

G4UAtomicDeexcitation::G4UAtomicDeexcitation():
  G4VAtomDeexcitation("UAtomDeexcitation"),
  minGammaEnergy(DBL_MAX), 
  minElectronEnergy(DBL_MAX),
  emcorr(0)
{
  PIXEshellCS    = 0;
  ePIXEshellCS   = 0;
  emcorr = G4LossTableManager::Instance()->EmCorrections();
  theElectron = G4Electron::Electron();
  thePositron = G4Positron::Positron();
  transitionManager = 0;
  anaPIXEshellCS = 0;
}

G4UAtomicDeexcitation::~G4UAtomicDeexcitation()
{
  delete PIXEshellCS;
  delete anaPIXEshellCS;
  delete ePIXEshellCS;
}

void G4UAtomicDeexcitation::InitialiseForNewRun()
{
  if(!IsFluoActive()) { return; }
  transitionManager = G4AtomicTransitionManager::Instance();
  if(IsPIXEActive()) {
    G4cout << G4endl;
    G4cout << "### === G4UAtomicDeexcitation::InitialiseForNewRun()" << G4endl;
    anaPIXEshellCS = new G4teoCrossSection("Analytical");
 
  }
  else  {return;}
  // initializing PIXE x-section name
  // 
  if (PIXECrossSectionModel() == "" ||
      PIXECrossSectionModel() == "Empirical" ||
      PIXECrossSectionModel() == "empirical") 
    {
      SetPIXECrossSectionModel("Empirical");
    }
  else if (PIXECrossSectionModel() == "ECPSSR_Analytical" ||
           PIXECrossSectionModel() == "Analytical" || 
           PIXECrossSectionModel() == "analytical") 
    {
      SetPIXECrossSectionModel("Analytical");
    }
  else if (PIXECrossSectionModel() == "ECPSSR_FormFactor" ||
           PIXECrossSectionModel() == "ECPSSR_Tabulated" ||
           PIXECrossSectionModel() == "Analytical_Tabulated") 
    {
      SetPIXECrossSectionModel("ECPSSR_FormFactor");
    }
  else 
    {
      G4cout << "### G4UAtomicDeexcitation::InitialiseForNewRun WARNING "
             << G4endl;
      G4cout << "    PIXE cross section name " << PIXECrossSectionModel()
             << " is unknown, Analytical cross section will be used" << G4endl; 
      SetPIXECrossSectionModel("Analytical");
    }
    
  // Check if old model should be deleted 
  if(PIXEshellCS) 
    {
      if(PIXECrossSectionModel() != PIXEshellCS->GetName()) 
        {
          delete PIXEshellCS;
          PIXEshellCS = 0;
        }
    }

  // Instantiate empirical model
  if(!PIXEshellCS) {
    if (PIXECrossSectionModel() == "Empirical")
      {
        PIXEshellCS = new G4empCrossSection("Empirical");
      }

    if (PIXECrossSectionModel() == "ECPSSR_FormFactor")
      {
        PIXEshellCS = new G4teoCrossSection("ECPSSR_FormFactor");
      }
  }

  // Electron cross section
  // initializing PIXE x-section name
  // 
  if (PIXEElectronCrossSectionModel() == "" ||
      PIXEElectronCrossSectionModel() == "Livermore")
    {
      SetPIXEElectronCrossSectionModel("Livermore");
    }
  else if (PIXEElectronCrossSectionModel() == "ProtonAnalytical" ||
           PIXEElectronCrossSectionModel() == "Analytical" || 
           PIXEElectronCrossSectionModel() == "analytical") 
    {
      SetPIXEElectronCrossSectionModel("ProtonAnalytical");
    }
  else if (PIXEElectronCrossSectionModel() == "ProtonEmpirical" ||
           PIXEElectronCrossSectionModel() == "Empirical" || 
           PIXEElectronCrossSectionModel() == "empirical") 
    {
      SetPIXEElectronCrossSectionModel("ProtonEmpirical");
    }
  else if (PIXEElectronCrossSectionModel() == "Penelope")
    SetPIXEElectronCrossSectionModel("Penelope");
  else 
    {
      G4cout << "### G4UAtomicDeexcitation::InitialiseForNewRun WARNING "
             << G4endl;
      G4cout << "    PIXE e- cross section name " << PIXEElectronCrossSectionModel()
             << " is unknown, PIXE is disabled" << G4endl; 
      SetPIXEElectronCrossSectionModel("Livermore");
    }
    
  // Check if old model should be deleted 
  if(ePIXEshellCS) 
    {
      if(PIXEElectronCrossSectionModel() != ePIXEshellCS->GetName()) 
        {
          delete ePIXEshellCS;
          ePIXEshellCS = 0;
        }
    }

  // Instantiate empirical model
  if(!ePIXEshellCS) 
    {
      if(PIXEElectronCrossSectionModel() == "Empirical")
        {
          ePIXEshellCS = new G4empCrossSection("Empirical");
        }

      else if(PIXEElectronCrossSectionModel() == "Analytical") 
        {
          ePIXEshellCS = new G4teoCrossSection("Analytical");
        }

      else if(PIXEElectronCrossSectionModel() == "Livermore")
        {
          ePIXEshellCS = new G4LivermoreIonisationCrossSection();
        }
      else if (PIXEElectronCrossSectionModel() == "Penelope")
        {
          ePIXEshellCS = new G4PenelopeIonisationCrossSection();
        }
    } 
}

void G4UAtomicDeexcitation::InitialiseForExtraAtom(G4int /*Z*/)
{}

const G4AtomicShell* G4UAtomicDeexcitation::GetAtomicShell(G4int Z, G4AtomicShellEnumerator shell)
{
  return transitionManager->Shell(Z, size_t(shell));
}

void G4UAtomicDeexcitation::GenerateParticles(
                      std::vector<G4DynamicParticle*>* vectorOfParticles,  
                      const G4AtomicShell* atomicShell, 
                      G4int Z,
                      G4double gammaCut,
                      G4double eCut)
{

  // Defined initial conditions
  G4int givenShellId = atomicShell->ShellId();
  //G4cout << "generating particles for vacancy in shellId: " << givenShellId << G4endl; // debug
  minGammaEnergy = gammaCut;
  minElectronEnergy = eCut;

  // V.I. short-cut
  //  if(!IsAugerActive()) {  minElectronEnergy = DBL_MAX; }

  // generation secondaries
  G4DynamicParticle* aParticle=0;
  G4int provShellId = 0;
  G4int counter = 0;
  
  // let's check that 5<Z<100

  if (Z>5 && Z<100) {

  // The aim of this loop is to generate more than one fluorecence photon 
  // from the same ionizing event 
    do
      {
        if (counter == 0) 
          // First call to GenerateParticles(...):
          // givenShellId is given by the process
          {
            provShellId = SelectTypeOfTransition(Z, givenShellId);

            if  ( provShellId >0) 
              {
                aParticle = GenerateFluorescence(Z,givenShellId,provShellId);
                //if (aParticle != 0) { G4cout << "****FLUO!_1**** " << aParticle->GetParticleDefinition()->GetParticleType() << " " << aParticle->GetKineticEnergy()/keV << G4endl ;} //debug  
              }
            else if ( provShellId == -1)
              {
                //              G4cout << "Try to generate Auger 1" << G4endl; //debug
                aParticle = GenerateAuger(Z, givenShellId);
                //              if (aParticle != 0) { G4cout << "****AUGER!****" << G4endl;} //debug
              }
            else
              {
                G4Exception("G4UAtomicDeexcitation::GenerateParticles()","de0002",JustWarning, "Energy deposited locally");
              }
          }
        else 
          // Following calls to GenerateParticles(...):
          // newShellId is given by GenerateFluorescence(...)
          {
            provShellId = SelectTypeOfTransition(Z,newShellId);
            if  (provShellId >0)
              {
                aParticle = GenerateFluorescence(Z,newShellId,provShellId);
                //if (aParticle != 0) { G4cout << "****FLUO!_2****" << aParticle->GetParticleDefinition()->GetParticleType() << " " << aParticle->GetKineticEnergy()/keV << G4endl;} //debug
              }
            else if ( provShellId == -1)
              {
                //              G4cout << "Try to generate Auger 2" << G4endl; //debug
                aParticle = GenerateAuger(Z, newShellId);
                //              if (aParticle != 0) { G4cout << "****AUGER!****" << G4endl;} //debug
              }
            else
              {
                G4Exception("G4UAtomicDeexcitation::GenerateParticles()","de0002",JustWarning, "Energy deposited locally");
              }
          }
        counter++;
        if (aParticle != 0) 
          {
            vectorOfParticles->push_back(aParticle);
            //G4cout << "Deexcitation Occurred!" << G4endl; //debug
          }
        else {provShellId = -2;}
      }  
    while (provShellId > -2); 
  }
  else
    {
      G4Exception("G4UAtomicDeexcitation::GenerateParticles()","de0001",JustWarning, "Energy deposited locally");
    }
  
  //G4cout << "---------FATTO!---------" << G4endl; //debug 

}

G4double 
G4UAtomicDeexcitation::GetShellIonisationCrossSectionPerAtom(
                               const G4ParticleDefinition* pdef, 
                               G4int Z, 
                               G4AtomicShellEnumerator shellEnum,
                               G4double kineticEnergy,
                               const G4Material* mat)
{

  // we must put a control on the shell that are passed: 
  // some shells should not pass (line "0" or "2")

  // check atomic number
  G4double xsec = 0.0;
  if(Z > 93 || Z < 6 ) { return xsec; } //corrected by alf - Z<6 missing
  G4int idx = G4int(shellEnum);
  if(idx >= G4AtomicShells::GetNumberOfShells(Z)) { return xsec; }

  // 
  if(pdef == theElectron || pdef == thePositron) {
    xsec = ePIXEshellCS->CrossSection(Z,shellEnum,kineticEnergy,0.0,mat);
    return xsec;
  }

  G4double mass = pdef->GetPDGMass();
  G4double escaled = kineticEnergy;
  G4double q2 = 0.0;

  // scaling to protons
  if ((pdef->GetParticleName() != "proton" && pdef->GetParticleName() != "alpha" ) )
  {
    mass = proton_mass_c2;
    escaled = kineticEnergy*mass/(pdef->GetPDGMass());

    if(mat) {
      q2 = emcorr->EffectiveChargeSquareRatio(pdef,mat,kineticEnergy);
    } else {
      G4double q = pdef->GetPDGCharge()/eplus;
      q2 = q*q;
    }
  }
  
  if(PIXEshellCS) { xsec = PIXEshellCS->CrossSection(Z,shellEnum,escaled,mass,mat); }
  if(xsec < 1e-100) { 
    
    xsec = anaPIXEshellCS->CrossSection(Z,shellEnum,escaled,mass,mat); 
    
  }

  if (q2)  {xsec *= q2;}

  return xsec;
}

void G4UAtomicDeexcitation::SetCutForSecondaryPhotons(G4double cut)
{
  minGammaEnergy = cut;
}

void G4UAtomicDeexcitation::SetCutForAugerElectrons(G4double cut)
{
  minElectronEnergy = cut;
}

G4double 
G4UAtomicDeexcitation::ComputeShellIonisationCrossSectionPerAtom(
                               const G4ParticleDefinition* p, 
                               G4int Z, 
                               G4AtomicShellEnumerator shell,
                               G4double kinE,
                               const G4Material* mat)
{
  return GetShellIonisationCrossSectionPerAtom(p,Z,shell,kinE,mat);
}

G4int G4UAtomicDeexcitation::SelectTypeOfTransition(G4int Z, G4int shellId)
{
  if (shellId <=0 ) {
    G4Exception("G4UAtomicDeexcitation::SelecttypeOfTransition()","de0002",JustWarning, "Energy deposited locally");
    return 0;
  }
  //G4bool fluoTransitionFoundFlag = false;
  
  G4int provShellId = -1;
  G4int shellNum = 0;
  G4int maxNumOfShells = transitionManager->NumberOfReachableShells(Z);  
  
  const G4FluoTransition* refShell = transitionManager->ReachableShell(Z,maxNumOfShells-1);

  // This loop gives shellNum the value of the index of shellId
  // in the vector storing the list of the shells reachable through
  // a radiative transition
  if ( shellId <= refShell->FinalShellId())
    {
      while (shellId != transitionManager->ReachableShell(Z,shellNum)->FinalShellId())
        {
          if(shellNum ==maxNumOfShells-1)
            {
              break;
            }
          shellNum++;
        }
      G4int transProb = 0; //AM change 29/6/07 was 1
   
      G4double partialProb = G4UniformRand();      
      G4double partSum = 0;
      const G4FluoTransition* aShell = transitionManager->ReachableShell(Z,shellNum);      
      G4int trSize =  (aShell->TransitionProbabilities()).size();
    
      // Loop over the shells wich can provide an electron for a 
      // radiative transition towards shellId:
      // in every loop the partial sum of the first transProb shells
      // is calculated and compared with a random number [0,1].
      // If the partial sum is greater, the shell whose index is transProb
      // is chosen as the starting shell for a radiative transition
      // and its identity is returned
      // Else, terminateded the loop, -1 is returned
      while(transProb < trSize){
        
         partSum += aShell->TransitionProbability(transProb);

         if(partialProb <= partSum)
           {
             provShellId = aShell->OriginatingShellId(transProb);
             //fluoTransitionFoundFlag = true;

             break;
           }
         transProb++;
      }

      // here provShellId is the right one or is -1.
      // if -1, the control is passed to the Auger generation part of the package 
    }
  else 
    {
      provShellId = -1;
    }
  //G4cout << "FlagTransition= " << provShellId << " ecut(MeV)= " << minElectronEnergy
  //     << "  gcut(MeV)= " << minGammaEnergy << G4endl;
  return provShellId;
}

G4DynamicParticle* 
G4UAtomicDeexcitation::GenerateFluorescence(G4int Z, G4int shellId,
                                            G4int provShellId )
{ 

  //if(!IsDeexActive()) { return 0; }

  if (shellId <=0 )

    {
      G4Exception("G4UAtomicDeexcitation::GenerateFluorescence()","de0002",JustWarning, "Energy deposited locally");
      return 0;
    }
  

  //isotropic angular distribution for the outcoming photon
  G4double newcosTh = 1.-2.*G4UniformRand();
  G4double newsinTh = std::sqrt((1.-newcosTh)*(1. + newcosTh));
  G4double newPhi = twopi*G4UniformRand();
  
  G4double xDir = newsinTh*std::sin(newPhi);
  G4double yDir = newsinTh*std::cos(newPhi);
  G4double zDir = newcosTh;
  
  G4ThreeVector newGammaDirection(xDir,yDir,zDir);
  
  G4int shellNum = 0;
  G4int maxNumOfShells = transitionManager->NumberOfReachableShells(Z);
  
  // find the index of the shell named shellId
  while (shellId != transitionManager->
         ReachableShell(Z,shellNum)->FinalShellId())
    {
      if(shellNum == maxNumOfShells-1)
        {
          break;
        }
      shellNum++;
    }
  // number of shell from wich an electron can reach shellId
  size_t transitionSize = transitionManager->
    ReachableShell(Z,shellNum)->OriginatingShellIds().size();
  
  size_t index = 0;
  
  // find the index of the shell named provShellId in the vector
  // storing the shells from which shellId can be reached 
  while (provShellId != transitionManager->
         ReachableShell(Z,shellNum)->OriginatingShellId(index))
    {
      if(index ==  transitionSize-1)
        {
          break;
        }
      index++;
    }
  // energy of the gamma leaving provShellId for shellId
  G4double transitionEnergy = transitionManager->
    ReachableShell(Z,shellNum)->TransitionEnergy(index);
  
  if (transitionEnergy < minGammaEnergy) return 0;

  // This is the shell where the new vacancy is: it is the same
  // shell where the electron came from
  newShellId = transitionManager->
    ReachableShell(Z,shellNum)->OriginatingShellId(index);
  
  
  G4DynamicParticle* newPart = new G4DynamicParticle(G4Gamma::Gamma(), 
                                                     newGammaDirection,
                                                     transitionEnergy);
  return newPart;
}

G4DynamicParticle* G4UAtomicDeexcitation::GenerateAuger(G4int Z, G4int shellId)
{
  if(!IsAugerActive()) { 
    //    G4cout << "auger inactive!" << G4endl; //debug
    return 0; 
  }
  
  if (shellId <=0 ) {
    

      G4Exception("G4UAtomicDeexcitation::GenerateAuger()","de0002",JustWarning, "Energy deposited locally");

      return 0;
    
  }

  // G4int provShellId = -1;
  G4int maxNumOfShells = transitionManager->NumberOfReachableAugerShells(Z);  
  
  const G4AugerTransition* refAugerTransition = 
        transitionManager->ReachableAugerShell(Z,maxNumOfShells-1);

  // This loop gives to shellNum the value of the index of shellId
  // in the vector storing the list of the vacancies in the variuos shells 
  // that can originate a NON-radiative transition
  
  G4int shellNum = 0;

  if ( shellId <= refAugerTransition->FinalShellId() ) 
    //"FinalShellId" is final from the point of view of the elctron who makes the transition, 
    // being the Id of the shell in which there is a vacancy
    {
      G4int pippo = transitionManager->ReachableAugerShell(Z,shellNum)->FinalShellId();
      if (shellId  != pippo ) {
        do { 
          shellNum++;
          if(shellNum == maxNumOfShells)
            {
              //              G4cout << "No Auger transition found" << G4endl; //debug
              return 0;
            }
        }
        while (shellId != (transitionManager->ReachableAugerShell(Z,shellNum)->FinalShellId()) ) ;
      }


      // Now we have that shellnum is the shellIndex of the shell named ShellId

      //      G4cout << " the index of the shell is: "<<shellNum<<G4endl;

      // But we have now to select two shells: one for the transition, 
      // and another for the auger emission.

      G4int transitionLoopShellIndex = 0;      
      G4double partSum = 0;
      const G4AugerTransition* anAugerTransition = 
            transitionManager->ReachableAugerShell(Z,shellNum);

      //      G4cout << " corresponding to the ID: "<< anAugerTransition->FinalShellId() << G4endl;


      G4int transitionSize = 
            (anAugerTransition->TransitionOriginatingShellIds())->size();
      while (transitionLoopShellIndex < transitionSize) {

        std::vector<G4int>::const_iterator pos = 
               anAugerTransition->TransitionOriginatingShellIds()->begin();

        G4int transitionLoopShellId = *(pos+transitionLoopShellIndex);
        G4int numberOfPossibleAuger = 
              (anAugerTransition->AugerTransitionProbabilities(transitionLoopShellId))->size();
        G4int augerIndex = 0;
        //      G4int partSum2 = 0;


        if (augerIndex < numberOfPossibleAuger) {
          
          do 
            {
              G4double thisProb = anAugerTransition->AugerTransitionProbability(augerIndex, 
                                                                                transitionLoopShellId);
              partSum += thisProb;
              augerIndex++;
              
            } while (augerIndex < numberOfPossibleAuger);
                }
        transitionLoopShellIndex++;
      }
      


      // Now we have the entire probability of an auger transition for the vacancy 
      // located in shellNum (index of shellId) 

      // AM *********************** F I X E D **************************** AM
      // Here we duplicate the previous loop, this time looking to the sum of the probabilities 
      // to be under the random number shoot by G4 UniformRdandom. This could have been done in the 
      // previuos loop, while integrating the probabilities. There is a bug that will be fixed 
      // 5 minutes from now: a line:
      // G4int numberOfPossibleAuger = (anAugerTransition->
      // AugerTransitionProbabilities(transitionLoopShellId))->size();
      // to be inserted.
      // AM *********************** F I X E D **************************** AM

      // Remains to get the same result with a single loop.

      // AM *********************** F I X E D **************************** AM
      // Another Bug: in EADL Auger Transition are normalized to all the transitions deriving from 
      // a vacancy in one shell, but not all of these are present in data tables. So if a transition 
      // doesn't occur in the main one a local energy deposition must occur, instead of (like now) 
      // generating the last transition present in EADL data.
      // AM *********************** F I X E D **************************** AM


      G4double totalVacancyAugerProbability = partSum;


      //And now we start to select the right auger transition and emission
      G4int transitionRandomShellIndex = 0;
      G4int transitionRandomShellId = 1;
      G4int augerIndex = 0;
      partSum = 0; 
      G4double partialProb = G4UniformRand();
      // G4int augerOriginatingShellId = 0;
      
      G4int numberOfPossibleAuger = 0;
      
      G4bool foundFlag = false;

      while (transitionRandomShellIndex < transitionSize) {

        std::vector<G4int>::const_iterator pos = 
               anAugerTransition->TransitionOriginatingShellIds()->begin();

        transitionRandomShellId = *(pos+transitionRandomShellIndex);
        
        augerIndex = 0;
        numberOfPossibleAuger = (anAugerTransition-> 
                                 AugerTransitionProbabilities(transitionRandomShellId))->size();

        while (augerIndex < numberOfPossibleAuger) {
          G4double thisProb =anAugerTransition->AugerTransitionProbability(augerIndex, 
                                                                           transitionRandomShellId);

          partSum += thisProb;
          
          if (partSum >= (partialProb*totalVacancyAugerProbability) ) { // was /
            foundFlag = true;
            break;
          }
          augerIndex++;
        }
        if (partSum >= (partialProb*totalVacancyAugerProbability) ) {break;} // was /
        transitionRandomShellIndex++;
      }

      // Now we have the index of the shell from wich comes the auger electron (augerIndex), 
      // and the id of the shell, from which the transition e- come (transitionRandomShellid)
      // If no Transition has been found, 0 is returned.  

      if (!foundFlag) {
        //      G4cout << "Auger not found (foundflag = false) " << G4endl; //debug
        return 0;

} 
      
      // Isotropic angular distribution for the outcoming e-
      G4double newcosTh = 1.-2.*G4UniformRand();
      G4double  newsinTh = std::sqrt(1.-newcosTh*newcosTh);
      G4double newPhi = twopi*G4UniformRand();
      
      G4double xDir =  newsinTh*std::sin(newPhi);
      G4double yDir = newsinTh*std::cos(newPhi);
      G4double zDir = newcosTh;
      
      G4ThreeVector newElectronDirection(xDir,yDir,zDir);
      
      // energy of the auger electron emitted
      
      
      G4double transitionEnergy = anAugerTransition->AugerTransitionEnergy(augerIndex, transitionRandomShellId);
      /*
        G4cout << "AUger TransitionId " << anAugerTransition->FinalShellId() << G4endl;
        G4cout << "augerIndex: " << augerIndex << G4endl;
        G4cout << "transitionShellId: " << transitionRandomShellId << G4endl;
      */
      
      if (transitionEnergy < minElectronEnergy) {
        // G4cout << "Problem!  (transitionEnergy < minElectronEnergy)" << G4endl; // debug
        // G4cout << "minElectronEnergy(KeV): " << minElectronEnergy/keV << G4endl; // debug
        // G4cout << "transitionEnergy(KeV): " << transitionEnergy/keV << G4endl; // debug
        return 0;
      }

      // This is the shell where the new vacancy is: it is the same
      // shell where the electron came from
      newShellId = transitionRandomShellId;
      
      return new G4DynamicParticle(G4Electron::Electron(), 
                                   newElectronDirection,
                                   transitionEnergy);
    }
  else 
    {
      //      G4cout << "G4UAtomicDeexcitation: no auger transition found" << G4endl ;
      //      G4cout << "( shellId <= refAugerTransition->FinalShellId() )" << G4endl;
      return 0;
    }
}