G4VXResonance Class Reference

#include <G4VXResonance.hh>

Inheritance diagram for G4VXResonance:

Public Member Functions
	G4VXResonance ()
virtual	~G4VXResonance ()
G4bool	operator== (const G4VXResonance &right) const
G4bool	operator!= (const G4VXResonance &right) const
Public Member Functions inherited from G4VCrossSectionSource
	G4VCrossSectionSource ()
virtual	~G4VCrossSectionSource ()
G4bool	operator== (const G4VCrossSectionSource &right) const
G4bool	operator!= (const G4VCrossSectionSource &right) const
virtual G4double	CrossSection (const G4KineticTrack &trk1, const G4KineticTrack &trk2) const =0
virtual const G4CrossSectionVector *	GetComponents () const =0
virtual G4String	Name () const =0
virtual void	Print () const
virtual void	PrintAll (const G4KineticTrack &trk1, const G4KineticTrack &trk2) const
virtual G4bool	IsValid (G4double e) const
virtual G4double	HighLimit () const
virtual G4double	LowLimit () const

Protected Member Functions
	G4VXResonance (const G4VXResonance &right)
G4VXResonance &	operator= (const G4VXResonance &right)
G4double	DegeneracyFactor (const G4KineticTrack &trk1, const G4KineticTrack &trk2, G4double iSpinOut1, G4double iSpinOut2) const
G4double	DetailedBalance (const G4KineticTrack &trk1, const G4KineticTrack &trk2, G4int isoOut1, G4int isoOut2, G4double iSpinOut1, G4double iSpinOut2, G4double mOut1, G4double mOut2) const
G4double	IsospinCorrection (const G4KineticTrack &trk1, const G4KineticTrack &trk2, G4int isoOut1, G4int isoOut2, G4double iSpinOut1, G4double iSpinOut2) const
Protected Member Functions inherited from G4VCrossSectionSource
G4bool	InLimits (G4double e, G4double eLow, G4double eHigh) const
const G4ParticleDefinition *	FindLightParticle (const G4KineticTrack &trk1, const G4KineticTrack &trk2) const
G4double	FcrossX (G4double e, G4double e0, G4double sigma, G4double eParam, G4double power) const
G4ParticleDefinition *	FindKeyParticle (const G4KineticTrack &trk1, const G4KineticTrack &trk2) const
G4double	GetTransversePionMass () const
G4double	GetMinStringMass () const

Detailed Description

Definition at line 54 of file G4VXResonance.hh.

Constructor & Destructor Documentation

G4VXResonance() [1/2]

G4VXResonance::G4VXResonance

(

)

Definition at line 50 of file G4VXResonance.cc.

{ }

~G4VXResonance()

G4VXResonance::~G4VXResonance ( )

virtual

Definition at line 54 of file G4VXResonance.cc.

{  }

G4VXResonance() [2/2]

G4VXResonance::G4VXResonance ( const G4VXResonance &  right )

protected

Member Function Documentation

DegeneracyFactor()

G4double G4VXResonance::DegeneracyFactor ( const G4KineticTrack &  trk1, const G4KineticTrack &  trk2, G4double  iSpinOut1, G4double  iSpinOut2  ) const

protected

Definition at line 186 of file G4VXResonance.cc.

{
  G4double value = 0.;
 
  G4ParticleDefinition* in1 = trk1.GetDefinition();
  G4ParticleDefinition* in2 = trk2.GetDefinition();
 
  G4double sIn1 =  in1->GetPDGiSpin()  + 1.;
  G4double sIn2 =  in2->GetPDGiSpin()  + 1.;
  
  G4double denom = sIn1 * sIn2;
  if (denom > 0.)
  {
    value = (iSpinOut1+1) * (iSpinOut2+1) / denom;
  }
  return value;
}

Referenced by DetailedBalance(), and IsospinCorrection().

DetailedBalance()

G4double G4VXResonance::DetailedBalance ( const G4KineticTrack &  trk1, const G4KineticTrack &  trk2, G4int  isoOut1, G4int  isoOut2, G4double  iSpinOut1, G4double  iSpinOut2, G4double  mOut1, G4double  mOut2  ) const

protected

Definition at line 124 of file G4VXResonance.cc.

{
  // To handle the cases when resonances are involved the modified
  // detailed balance of P. Danielewicz and G.F. Bertsch, Nucl. Phys. A533(1991) 712
  // is used; in other words, the width of the resonances are folded to get the
  // mean square of the final state momentum.
 
  G4ParticleDefinition* in1 = trk1.GetDefinition();
  G4ParticleDefinition* in2 = trk2.GetDefinition();
  if(in1->IsShortLived() && in2->IsShortLived())
  {
    throw G4HadronicException(__FILE__, __LINE__, "Detailed balance for resonance scattering still on the schedule.");
  }
 
  G4double result = 0.;
 
  G4int isoIn1 = in1->GetPDGiIsospin();
  G4int iso3In1 = in1->GetPDGiIsospin3();
  G4int isoIn2 = in2->GetPDGiIsospin();
  G4int iso3In2 = in2->GetPDGiIsospin3();  
  G4double weight = clebsch.Weight(isoIn1, iso3In1, isoIn2, iso3In2, isoOut1, isoOut2);
  
  if (weight > 00001)
  {
    // adding spin counting here ...... does not look quite consistent, but is correct anyway. 
    // revisit in the next design iteration @@
    G4double degeneracy = DegeneracyFactor(trk1,trk2,iSpinOut1,iSpinOut2);
    G4double factor = degeneracy * weight;
 
    // now the phase-space
    G4double S = (trk1.Get4Momentum() + trk2.Get4Momentum()).mag2();
    G4double m_1 = in1->GetPDGMass();
    G4double m_2 = in2->GetPDGMass();
    
    // on-shell
    G4double pinitial2 = (S - (m_1+m_2) * (m_1+m_2)) * (S - (m_1-m_2) * (m_1-m_2)) / (4.0*S);
    G4double pfinal2 = (S - (mOut1+mOut2) * (mOut1+mOut2)) * (S - ( mOut1-mOut2) * (mOut1-mOut2)) / (4.0*S);
    G4double relativeMomsquared = pfinal2/pinitial2;
 
    // resonance-nucleon scattering - inverse channel
    if(in1->IsShortLived())
    {
      G4DetailedBalancePhaseSpaceIntegral theI(in1);
      relativeMomsquared = 1./theI.GetPhaseSpaceIntegral(std::sqrt(S));
    }
    else if(in2->IsShortLived())
    {
      G4DetailedBalancePhaseSpaceIntegral theI(in2);
      relativeMomsquared = 1./theI.GetPhaseSpaceIntegral(std::sqrt(S));
    }
 
    result = factor * relativeMomsquared;
  }
 
  return result;
}

Referenced by G4XResonance::CrossSection().

IsospinCorrection()

G4double G4VXResonance::IsospinCorrection ( const G4KineticTrack &  trk1, const G4KineticTrack &  trk2, G4int  isoOut1, G4int  isoOut2, G4double  iSpinOut1, G4double  iSpinOut2  ) const

protected

Definition at line 70 of file G4VXResonance.cc.

{
  G4double result = 0.;
 
  G4ParticleDefinition* in1 = trk1.GetDefinition();
  G4ParticleDefinition* in2 = trk2.GetDefinition();
 
  G4int isoIn1  = in1->GetPDGiIsospin();
  G4int iso3In1 = in1->GetPDGiIsospin3();
  G4int isoIn2  = in2->GetPDGiIsospin();
  G4int iso3In2 = in2->GetPDGiIsospin3();
 
  G4int isoProton = G4Proton::ProtonDefinition()->GetPDGiIsospin();
  G4int iso3Proton = G4Proton::ProtonDefinition()->GetPDGiIsospin3();
  
  G4double pWeight = clebsch.Weight(isoProton,iso3Proton, isoProton,iso3Proton, isoOut1,isoOut2);
  if (pWeight == 0.) throw G4HadronicException(__FILE__, __LINE__, "G4VXResonance::IsospinCorrection, no resonances - pWeight is zero");
 
  if (in1->IsShortLived() || in2->IsShortLived())
  {
    // Resonances in the initial state
    G4int iSpinProton = G4Proton::ProtonDefinition()->GetPDGiSpin();
    G4double degeneracyFactor = DegeneracyFactor(trk1,trk2,iSpinProton,iSpinProton);
 
    G4double factor = degeneracyFactor * pWeight;
    if (factor > DBL_MIN)
    {
      // Randomly select the Isospin3 of the initial state resonances
      std::vector<G4double> iso = clebsch.GenerateIso3(isoIn1,iso3In1, 
                          isoIn2,iso3In2, 
                          isoProton,isoProton);
      G4int isoA = G4lrint(iso[0]);
      G4int isoB = G4lrint(iso[1]);
      G4double rWeight =  clebsch.Weight(isoProton,isoA,
                     isoProton,isoB,
                     isoOut1,isoOut2);
      result = rWeight / pWeight;
    }
  }
  else
  {
    G4double weight = clebsch.Weight(isoIn1,iso3In1, isoIn2,iso3In2, isoOut1,isoOut2);
    result = weight / pWeight;
  }
  
  return result;
}

Referenced by G4XResonance::CrossSection().

operator!=()

G4bool G4VXResonance::operator!=

(

const G4VXResonance &

right

)

const

Definition at line 64 of file G4VXResonance.cc.

{
  return (this != (G4VXResonance *) &right);
}

operator=()

G4VXResonance & G4VXResonance::operator= ( const G4VXResonance &  right )

protected

operator==()

G4bool G4VXResonance::operator==

(

const G4VXResonance &

right

)

const

Definition at line 58 of file G4VXResonance.cc.

{
  return (this == (G4VXResonance *) &right);
}

---

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

• G4VXResonance.hh
• G4VXResonance.cc