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PYTHIA
8.311
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#include <HelicityMatrixElements.h>
Public Member Functions | |
| void | initConstants () |
| Helicity matrix element for two fermions -> photon/Z/Z' -> two fermions. More... | |
| void | initWaves (vector< HelicityParticle > &) |
| Initialize wave functions for the helicity matrix element. More... | |
| complex | calculateME (vector< int >) |
| Return element for the helicity matrix element. | |
 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 HelicityMatrixElement * | initChannel (vector< HelicityParticle > &) |
| Initialize the channel. More... | |
| virtual double | decayWeight (vector< HelicityParticle > &) |
| Calculate the matrix element weight for a decay. More... | |
| virtual double | decayWeightMax (vector< HelicityParticle > &) |
| Calculate the maximum matrix element decay weight. | |
| 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. | |
Additional Inherited Members | |
| Protected Attributes inherited from HelicityMatrixElement | |
| double | DECAYWEIGHTMAX |
| Maximum decay weight. WARNING: hardcoded constant. | |
| vector< GammaMatrix > | gamma |
| 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. | |
| ParticleData * | particleDataPtr |
| Pointer to particle data. | |
| CoupSM * | coupSMPtr |
| Pointer to Standard Model constants. | |
| Settings * | settingsPtr |
| Pointer to Settings. | |
Helicity matrix element for the hard process of two fermions -> photon/Z/Z' -> two fermions.
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virtual |
Helicity matrix element for two fermions -> photon/Z/Z' -> two fermions.
Note that there is a double contraction in the Z matrix element, which can be very time consuming. If the two incoming fermions are oriented along the z-axis, their helicities must be opposite for a non-zero matrix element term. Consequently, this check is made to help speed up the matrix element. p0Q: charge of the incoming fermion line p2Q: charge of the outgoing fermion line s: center of mass energy sin2W: sine of the Weinberg angle cos2W: cosine of the Weinberg angle zM: on-shell mass of the Z zG: on-shell width of the Z p0CA: axial coupling of particle 0 to the Z p2CA: axial coupling of particle 2 to the Z p0CV: vector coupling of particle 0 to the Z p2CV: vector coupling of particle 2 to the Z zaxis: true if the incoming fermions are oriented along the z-axis Initialize the constants for the helicity matrix element.
Set the Weinberg angle.
Set the on-shell Z/Z' mass and width.
Set the Z vector and axial couplings to the fermions.
Turn off the gamma/Z/Z' channels.
Set the Z' vector and axial couplings to the fermions.
Set the gamma/Z/Z' channels to include.
Default behavior without settings pointer.
Massless approximation for ffbar -> Z -> ffbar.
Reimplemented from HelicityMatrixElement.
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virtual |
Initialize wave functions for the helicity matrix element.
Fermion line charge.
Center of mass energy.
Check if incoming fermions are oriented along z-axis.
Reimplemented from HelicityMatrixElement.
1.8.11
