G4Evaporation Class Reference

#include <G4Evaporation.hh>

Inheritance diagram for G4Evaporation:

Public Member Functions
	G4Evaporation ()
	G4Evaporation (G4VEvaporationChannel *photoEvaporation)
virtual	~G4Evaporation ()
virtual void	Initialise ()
G4FragmentVector *	BreakItUp (const G4Fragment &theNucleus)
void	SetDefaultChannel ()
void	SetGEMChannel ()
void	SetCombinedChannel ()
virtual void	SetPhotonEvaporation (G4VEvaporationChannel *ptr)

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Detailed Description

Definition at line 53 of file G4Evaporation.hh.

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Constructor & Destructor Documentation

G4Evaporation::G4Evaporation

(

)

Definition at line 59 of file G4Evaporation.cc.

References SetPhotonEvaporation(), and G4VEvaporation::thePhotonEvaporation.

  : theChannels(0),nChannels(0)
{
  SetPhotonEvaporation(new G4PhotonEvaporation());
  theChannelFactory = new G4EvaporationDefaultGEMFactory(thePhotonEvaporation);
  SetParameters();
  InitialiseEvaporation();
}

G4Evaporation::G4Evaporation

(

G4VEvaporationChannel *

photoEvaporation

)

Definition at line 68 of file G4Evaporation.cc.

References SetPhotonEvaporation(), and G4VEvaporation::thePhotonEvaporation.

  : theChannels(0),nChannels(0)
{
  if(photoEvaporation) { SetPhotonEvaporation(photoEvaporation); }
  else                 { SetPhotonEvaporation(new G4PhotonEvaporation()); }

  theChannelFactory = new G4EvaporationDefaultGEMFactory(thePhotonEvaporation);
  SetParameters();
  InitialiseEvaporation();
}

G4Evaporation::~G4Evaporation

(

)

[virtual]

Definition at line 99 of file G4Evaporation.cc.

References G4VEvaporation::thePhotonEvaporation.

{
  CleanChannels();
  delete thePhotonEvaporation;
  delete theChannelFactory; 
}

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Member Function Documentation

G4FragmentVector * G4Evaporation::BreakItUp

(

const G4Fragment &

theNucleus

)

[virtual]

Implements G4VEvaporation.

Definition at line 165 of file G4Evaporation.cc.

References G4UnstableFragmentBreakUp::BreakUpFragment(), G4UniformRand, G4Fragment::GetA_asInt(), G4Fragment::GetExcitationEnergy(), G4NistManager::GetIsotopeAbundance(), and G4Fragment::GetZ_asInt().

{
  G4FragmentVector * theResult = new G4FragmentVector;
  G4FragmentVector * theTempResult;
  const G4double Elimit = 3*MeV;

  // The residual nucleus (after evaporation of each fragment)
  G4Fragment* theResidualNucleus = new G4Fragment(theNucleus);

  G4double totprob, prob, oldprob = 0.0;
  size_t maxchannel, i;

  G4int Amax = theResidualNucleus->GetA_asInt();

  // Starts loop over evaporated particles, loop is limited by number
  // of nucleons
  for(G4int ia=0; ia<Amax; ++ia) {
 
    // g,n,p and light fragments - evaporation is finished
    G4int Z = theResidualNucleus->GetZ_asInt();
    G4int A = theResidualNucleus->GetA_asInt();

    // stop deecitation loop if can be deexcited by FBU
    if(maxZforFBU > Z && maxAforFBU >= A) {
      theResult->push_back(theResidualNucleus);
      return theResult;
    }

    // check if it is stable, then finish evaporation
    G4double abun = nist->GetIsotopeAbundance(Z, A); 
    /*
    G4cout << "### G4Evaporation::BreakItUp step " << ia << " Z= " << Z
           << " A= " << A << " Eex(MeV)= " 
           << theResidualNucleus->GetExcitationEnergy()
           << " aban= " << abun << G4endl;
    */
    // stop deecitation loop in the case of the cold stable fragment 
    G4double Eex = theResidualNucleus->GetExcitationEnergy();
    if(Eex <= minExcitation && abun > 0.0) {
      theResult->push_back(theResidualNucleus);
      return theResult;
    }
 
    totprob = 0.0;
    maxchannel = nChannels;
    /*
    G4cout << "### Evaporation loop #" << ia 
           << "  Fragment: " << theResidualNucleus << G4endl;
    */
    // loop over evaporation channels
    for(i=0; i<nChannels; ++i) {
      prob = (*theChannels)[i]->GetEmissionProbability(theResidualNucleus);
      //G4cout << "  Channel# " << i << "  prob= " << prob << G4endl; 

      totprob += prob;
      probabilities[i] = totprob;
      // if two recent probabilities are near zero stop computations
      if(i>=8) {
        if(prob <= totprob*1.e-8 && oldprob <= totprob*1.e-8) {
          maxchannel = i+1; 
          break;
        }
      }
      oldprob = prob;
      // protection for very excited fragment - avoid GEM
      if(7 == i && Eex > Elimit*A) {
        maxchannel = 8;
        break;
      }
    }

    // photon evaporation in the case of no other channels available
    // do evaporation chain and reset total probability
    if(0.0 < totprob && probabilities[0] == totprob) {
      //G4cout << "Start gamma evaporation" << G4endl;
      theTempResult = (*theChannels)[0]->BreakUpFragment(theResidualNucleus);
      if(theTempResult) {
        size_t nsec = theTempResult->size();
        for(size_t j=0; j<nsec; ++j) {
          theResult->push_back((*theTempResult)[j]);
        }
        delete theTempResult;
      }
      totprob = 0.0;
    }

    // stable fragnent - evaporation is finished
    if(0.0 == totprob) {

      // if fragment is exotic, then try to decay it
      if(0.0 == abun && Z < 20) {
        //G4cout << "$$$ Decay exotic fragment" << G4endl;
        theTempResult = unstableBreakUp.BreakUpFragment(theResidualNucleus);
        if(theTempResult) {
          size_t nsec = theTempResult->size();
          for(size_t j=0; j<nsec; ++j) {
            theResult->push_back((*theTempResult)[j]);
          }
          delete theTempResult;
        }
      }

      // save residual fragment
      theResult->push_back(theResidualNucleus);
      return theResult;
    }


    // select channel
    totprob *= G4UniformRand();
    // loop over evaporation channels
    for(i=0; i<maxchannel; ++i) { if(probabilities[i] >= totprob) { break; } }

    // this should not happen
    if(i >= nChannels) { i = nChannels - 1; }


    // single photon evaporation, primary pointer is kept
    if(0 == i) {
      //G4cout << "Single gamma" << G4endl;
      G4Fragment* gamma = (*theChannels)[0]->EmittedFragment(theResidualNucleus);
      if(gamma) { theResult->push_back(gamma); }

      // fission, return results to the main loop if fission is succesful
    } else if(1 == i) {
      //G4cout << "Fission" << G4endl;
      theTempResult = (*theChannels)[1]->BreakUp(*theResidualNucleus);
      if(theTempResult) {
        size_t nsec = theTempResult->size();
        G4bool deletePrimary = true;
        for(size_t j=0; j<nsec; ++j) {
          if(theResidualNucleus == (*theTempResult)[j]) { deletePrimary = false; }
          theResult->push_back((*theTempResult)[j]);
        }
        if(deletePrimary) { delete theResidualNucleus; }
        delete theTempResult;
        return theResult;
      }

      // other channels
    } else {
      //G4cout << "Channel # " << i << G4endl;
      theTempResult = (*theChannels)[i]->BreakUp(*theResidualNucleus);
      if(theTempResult) {
        size_t nsec = theTempResult->size();
        if(nsec > 0) {
          --nsec;
          for(size_t j=0; j<nsec; ++j) {
            theResult->push_back((*theTempResult)[j]);
          }
          // if the residual change its pointer 
          // then delete previous residual fragment and update to the new
          if(theResidualNucleus != (*theTempResult)[nsec] ) { 
            delete theResidualNucleus; 
            theResidualNucleus = (*theTempResult)[nsec];
          }
        }
        delete theTempResult;
      }
    }
  }

  // loop is stopped, save residual
  theResult->push_back(theResidualNucleus);
  
  return theResult;
}

void G4Evaporation::Initialise

(

)

[virtual]

Reimplemented from G4VEvaporation.

Definition at line 130 of file G4Evaporation.cc.

References G4VEvaporation::OPTxs, G4VEvaporation::SetOPTxs(), and G4VEvaporation::useSICB.

{
  for(size_t i=0; i<nChannels; ++i) {
    (*theChannels)[i]->SetOPTxs(OPTxs);
    (*theChannels)[i]->UseSICB(useSICB);
  }
}

void G4Evaporation::SetCombinedChannel

(

)

Definition at line 152 of file G4Evaporation.cc.

References G4VEvaporation::thePhotonEvaporation.

{
  delete theChannelFactory;
  theChannelFactory = new G4EvaporationDefaultGEMFactory(thePhotonEvaporation);
  InitialiseEvaporation();
}

void G4Evaporation::SetDefaultChannel

(

)

Definition at line 138 of file G4Evaporation.cc.

References G4VEvaporation::thePhotonEvaporation.

{
  delete theChannelFactory;
  theChannelFactory = new G4EvaporationFactory(thePhotonEvaporation);
  InitialiseEvaporation();
}

void G4Evaporation::SetGEMChannel

(

)

Definition at line 145 of file G4Evaporation.cc.

References G4VEvaporation::thePhotonEvaporation.

{
  delete theChannelFactory;
  theChannelFactory = new G4EvaporationGEMFactory(thePhotonEvaporation);
  InitialiseEvaporation();
}

void G4Evaporation::SetPhotonEvaporation

(

G4VEvaporationChannel *

ptr

)

[virtual]

Reimplemented from G4VEvaporation.

Definition at line 159 of file G4Evaporation.cc.

References G4VEvaporation::SetPhotonEvaporation().

Referenced by G4Evaporation().

{
  if(ptr) { G4VEvaporation::SetPhotonEvaporation(ptr); }
  if(0 < nChannels) { (*theChannels)[0] = ptr; }
}

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The documentation for this class was generated from the following files:

• G4Evaporation.hh
• G4Evaporation.cc

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