G4DecayWithSpin Class Reference

#include <G4DecayWithSpin.hh>

Inheritance diagram for G4DecayWithSpin:

Public Member Functions
	G4DecayWithSpin (const G4String &processName="DecayWithSpin")
virtual	~G4DecayWithSpin ()
Protected Member Functions
virtual G4VParticleChange *	DecayIt (const G4Track &aTrack, const G4Step &aStep)

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Detailed Description

Definition at line 43 of file G4DecayWithSpin.hh.

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Constructor & Destructor Documentation

G4DecayWithSpin::G4DecayWithSpin

(

const G4String &

processName = "DecayWithSpin"

)

Definition at line 52 of file G4DecayWithSpin.cc.

References DECAY_WithSpin, and G4VProcess::SetProcessSubType().

                                                           :G4Decay(processName)
{
  // set Process Sub Type   
  SetProcessSubType(static_cast<int>(DECAY_WithSpin));

}

G4DecayWithSpin::~G4DecayWithSpin

(

)

[virtual]

Definition at line 59 of file G4DecayWithSpin.cc.

{}

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Member Function Documentation

G4VParticleChange * G4DecayWithSpin::DecayIt	(	const G4Track &	aTrack,
		const G4Step &	aStep
	)			[protected, virtual]

Reimplemented from G4Decay.

Definition at line 61 of file G4DecayWithSpin.cc.

References G4Decay::DecayIt(), G4Decay::fRemainderLifeTime, G4UniformRand, G4PropagatorInField::GetCurrentFieldManager(), G4ParticleDefinition::GetDecayTable(), G4DynamicParticle::GetDefinition(), G4FieldManager::GetDetectorField(), G4Track::GetDynamicParticle(), G4Track::GetGlobalTime(), G4DynamicParticle::GetPolarization(), G4StepPoint::GetPosition(), G4Step::GetPostStepPoint(), G4TransportationManager::GetPropagatorInField(), G4Step::GetTrack(), G4TransportationManager::GetTransportationManager(), G4Track::GetVolume(), G4ParticleChangeForDecay::ProposePolarization(), G4DecayTable::SelectADecayChannel(), and G4MuonDecayChannelWithSpin::SetPolarization().

{

// get particle
  const G4DynamicParticle* aParticle = aTrack.GetDynamicParticle();
  const G4ParticleDefinition* aParticleDef = aParticle->GetDefinition();

// get parent_polarization
  G4ThreeVector parent_polarization = aParticle->GetPolarization();

  if(parent_polarization == G4ThreeVector(0,0,0))
  {
    // Generate random polarization direction

    G4double cost = 1. - 2.*G4UniformRand();
    G4double sint = std::sqrt((1.-cost)*(1.+cost));

    G4double phi = twopi*G4UniformRand();
    G4double sinp = std::sin(phi);
    G4double cosp = std::cos(phi);

    G4double px = sint*cosp;
    G4double py = sint*sinp;
    G4double pz = cost;

    parent_polarization.setX(px);
    parent_polarization.setY(py);
    parent_polarization.setZ(pz);

  }else{

    G4FieldManager* fieldMgr = aStep.GetTrack()->GetVolume()->
                                     GetLogicalVolume()->GetFieldManager();

    if (!fieldMgr) {
       G4TransportationManager *transportMgr =
                         G4TransportationManager::GetTransportationManager();
       G4PropagatorInField* fFieldPropagator = 
                                        transportMgr->GetPropagatorInField();
       if (fFieldPropagator) fieldMgr = 
                                  fFieldPropagator->GetCurrentFieldManager();
    }

    const G4Field* field = NULL;
    if(fieldMgr)field = fieldMgr->GetDetectorField();

    if (field) {

       G4double point[4];
       point[0] = (aStep.GetPostStepPoint()->GetPosition())[0];
       point[1] = (aStep.GetPostStepPoint()->GetPosition())[1];
       point[2] = (aStep.GetPostStepPoint()->GetPosition())[2];
       point[3] = aTrack.GetGlobalTime();

       G4double fieldValue[6];
       field -> GetFieldValue(point,fieldValue);

       G4ThreeVector B(fieldValue[0],fieldValue[1],fieldValue[2]);

       // Call the spin precession only for non-zero mag. field
       if (B.mag2() > 0.) parent_polarization = 
                                 Spin_Precession(aStep,B,fRemainderLifeTime);

    }
  }

// decay table
  G4DecayTable *decaytable = aParticleDef->GetDecayTable();

  if (decaytable) {
     G4MuonDecayChannelWithSpin *decaychannel;
     decaychannel = (G4MuonDecayChannelWithSpin*)decaytable->SelectADecayChannel();
     if (decaychannel) decaychannel->SetPolarization(parent_polarization);
  }

  G4ParticleChangeForDecay* pParticleChangeForDecay;

  pParticleChangeForDecay = (G4ParticleChangeForDecay*)G4Decay::DecayIt(aTrack,aStep);

  pParticleChangeForDecay->ProposePolarization(parent_polarization);

  return pParticleChangeForDecay;

}

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

• G4DecayWithSpin.hh
• G4DecayWithSpin.cc

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