PYTHIA  8.303
Public Member Functions | Protected Types | Protected Member Functions | Protected Attributes | List of all members
HMETau2ThreeMesons Class Reference

Helicity matrix element for a tau decay into three mesons (base class). More...

#include <HelicityMatrixElements.h>

Inheritance diagram for HMETau2ThreeMesons:
HMETauDecay HelicityMatrixElement HMETau2ThreeMesonsGeneric HMETau2ThreeMesonsWithKaons HMETau2ThreePions

Public Member Functions

void initConstants ()
 Initialize constants for the helicity matrix element. More...
 
void initHadronicCurrent (vector< HelicityParticle > &)
 Initialize the hadronic current for the helicity matrix element. More...
 
- Public Member Functions inherited from HMETauDecay
virtual void initWaves (vector< HelicityParticle > &)
 Initialize wave functions for the helicity matrix element. More...
 
virtual complex calculateME (vector< int >)
 Return element for the helicity matrix element.
 
virtual double decayWeightMax (vector< HelicityParticle > &)
 Return the maximum decay weight for the helicity matrix element. More...
 
- Public Member Functions inherited from HelicityMatrixElement
 HelicityMatrixElement ()
 Constructor and destructor.
 
virtual void initPointers (ParticleData *, CoupSM *, Settings *=0)
 Initialize the physics matrices and pointers. More...
 
virtual HelicityMatrixElementinitChannel (vector< HelicityParticle > &)
 Initialize the channel. More...
 
virtual double decayWeight (vector< HelicityParticle > &)
 Calculate the matrix element weight for a decay. More...
 
virtual void calculateD (vector< HelicityParticle > &)
 Calculate the decay matrix for a particle. More...
 
virtual void calculateRho (unsigned int, vector< HelicityParticle > &)
 Calculate the density matrix for a particle. More...
 
void setFermionLine (int, HelicityParticle &, HelicityParticle &)
 Set a fermion line. More...
 
virtual complex breitWigner (double s, double M, double G)
 Calculate Breit-Wigner's with running widths and fixed. More...
 
virtual complex sBreitWigner (double m0, double m1, double s, double M, double G)
 Return an s-wave BreitWigner.
 
virtual complex pBreitWigner (double m0, double m1, double s, double M, double G)
 Return a p-wave BreitWigner.
 
virtual complex dBreitWigner (double m0, double m1, double s, double M, double G)
 Return a d-wave BreitWigner.
 

Protected Types

enum  Mode {
  Pi0Pi0Pim, PimPimPip, Pi0PimK0b, PimPipKm,
  Pi0PimEta, PimKmKp, Pi0K0Km, KlPimKs,
  Pi0Pi0Km, KlKlPim, PimKsKs, PimK0bK0,
  Uknown
}
 Decay mode of the tau.
 

Protected Member Functions

virtual void initMode ()
 Initialize decay mode and resonance constants (called by initConstants). More...
 
virtual void initResonances ()
 
virtual void initMomenta (vector< HelicityParticle > &)
 Initialize the momenta. More...
 
virtual complex F1 ()
 Form factors.
 
virtual complex F2 ()
 
virtual complex F3 ()
 
virtual complex F4 ()
 
virtual double a1PhaseSpace (double)
 Phase space and Breit-Wigner for the a1. More...
 
virtual complex a1BreitWigner (double)
 
complex T (double m0, double m1, double s, vector< double > &M, vector< double > &G, vector< double > &W)
 Sum running p and fixed width Breit-Wigner resonances. More...
 
complex T (double s, vector< double > &M, vector< double > &G, vector< double > &W)
 Return summed weighted fixed width Breit-Wigner resonances.
 
- Protected Member Functions inherited from HMETauDecay
virtual void calculateResonanceWeights (vector< double > &, vector< double > &, vector< complex > &)
 Calculate complex resonance weights given a phase and amplitude vector.
 

Protected Attributes

Mode mode {}
 
double s1 {}
 Center of mass energies and momenta.
 
double s2 {}
 
double s3 {}
 
double s4 {}
 
Wave4 q {}
 
Wave4 q2 {}
 
Wave4 q3 {}
 
Wave4 q4 {}
 
complex a1BW {}
 Stored a1 Breit-Wigner (for speed).
 
- Protected Attributes inherited from HelicityMatrixElement
double DECAYWEIGHTMAX
 Maximum decay weight. WARNING: hardcoded constant.
 
vector< GammaMatrixgamma
 Physics matrices.
 
vector< int > pMap
 Particle map vector.
 
vector< int > pID
 Particle ID vector.
 
vector< double > pM
 Particle mass vector.
 
vector< vector< Wave4 > > u
 Wave functions.
 
ParticleDataparticleDataPtr
 Pointer to particle data.
 
CoupSMcoupSMPtr
 Pointer to Standard Model constants.
 
SettingssettingsPtr
 Pointer to Settings.
 

Detailed Description

Helicity matrix element for a tau decay into three mesons (base class).

Member Function Documentation

complex a1BreitWigner ( double  s)
protectedvirtual

Return the Breit-Wigner for the a1. Implements equation 3.18 of Z. Phys. C48 (1990) 445-452.

Mass of the a1.

Width of the a1.

double a1PhaseSpace ( double  s)
protectedvirtual

Phase space and Breit-Wigner for the a1.

Return the phase space factor for the a1. Implements equation 3.16 of Z. Phys. C48 (1990) 445-452.

Mass of the charged pion.

Mass of the rho.

void initConstants ( )
virtual

Initialize constants for the helicity matrix element.

Tau decay matrix element for tau decay into three mesons. This matrix element provides a base class for all implemented three meson decays. mode: three meson decay mode of the tau initMode(): initialize the decay mode initResonances(): initialize the resonance constants s1, s2, s3, s4: center-of-mass energies q, q2, q3, q4: summed and individual hadronic momentum four-vectors a1BW: stored value of a1BreitWigner for speed a1PhaseSpace(s): phase space factor for the a1 a1BreitWigner(s): Breit-Wigner for the a1 T(m0, m1, s, M, G, W): sum weighted p-wave Breit-Wigners T(s, M, G, W): sum weighted fixed width Breit-Wigners F1(), F2(), F3(), F4(): sub-current form factors

Reimplemented from HelicityMatrixElement.

void initHadronicCurrent ( vector< HelicityParticle > &  p)
virtual

Initialize the hadronic current for the helicity matrix element.

Initialize the momenta.

Calculate the center of mass energies.

Calculate the form factors.

Calculate the hadronic current.

Reimplemented from HMETauDecay.

void initMode ( )
protectedvirtual

Initialize decay mode and resonance constants (called by initConstants).

Initialize the tau decay mode.

void initMomenta ( vector< HelicityParticle > &  p)
protectedvirtual

Initialize the momenta.

Initialize the momenta for the helicity matrix element.

pi-, pi-, pi+ decay and pi0, pi0, pi- decay.

K-, pi-, K+ decay.

K0, pi-, Kbar0 decay.

K_S0, pi-, K_S0 decay.

K_L0, pi-, K_L0 decay.

K_S0, pi-, K_L0 decay.

K-, pi0, K0 decay.

pi0, pi0, K- decay.

K-, pi-, pi+ decay.

pi-, Kbar0, pi0 decay.

pi-, pi0, eta decay.

complex T ( double  m0,
double  m1,
double  s,
vector< double > &  M,
vector< double > &  G,
vector< double > &  W 
)
protected

Sum running p and fixed width Breit-Wigner resonances.

Return summed weighted running p Breit-Wigner resonances.


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