1 | // TauDecays.h is a part of the PYTHIA event generator. |
---|
2 | // Copyright (C) 2012 Philip Ilten, Torbjorn Sjostrand. |
---|
3 | // PYTHIA is licenced under the GNU GPL version 2, see COPYING for details. |
---|
4 | // Please respect the MCnet Guidelines, see GUIDELINES for details. |
---|
5 | |
---|
6 | // Header file for the TauDecays class. |
---|
7 | |
---|
8 | #ifndef Pythia8_TauDecays_H |
---|
9 | #define Pythia8_TauDecays_H |
---|
10 | |
---|
11 | #include "Basics.h" |
---|
12 | #include "Event.h" |
---|
13 | #include "HelicityBasics.h" |
---|
14 | #include "HelicityMatrixElements.h" |
---|
15 | #include "PythiaComplex.h" |
---|
16 | #include "PythiaStdlib.h" |
---|
17 | #include "Settings.h" |
---|
18 | |
---|
19 | namespace Pythia8 { |
---|
20 | |
---|
21 | //========================================================================== |
---|
22 | |
---|
23 | // TauDecays class. |
---|
24 | // This class decays tau leptons, with helicity information. |
---|
25 | |
---|
26 | class TauDecays { |
---|
27 | |
---|
28 | public: |
---|
29 | |
---|
30 | // Constructor and destructor. |
---|
31 | TauDecays() {}; |
---|
32 | ~TauDecays() {} |
---|
33 | |
---|
34 | // Initializer. |
---|
35 | void init(Info* infoPtrIn, Settings* settingsPtrIn, |
---|
36 | ParticleData* particleDataPtrIn, Rndm* rndmPtrIn, |
---|
37 | Couplings* couplingsPtrIn); |
---|
38 | |
---|
39 | // Decay a tau or correlated tau pair. |
---|
40 | bool decay(int iDec, Event& event); |
---|
41 | |
---|
42 | // Choose a decay channel for a particle. |
---|
43 | vector<HelicityParticle> createChildren(HelicityParticle parent); |
---|
44 | |
---|
45 | // Perform an N-body isotropic decay. |
---|
46 | void isotropicDecay(vector<HelicityParticle>& p); |
---|
47 | |
---|
48 | // Write the decay to event record. |
---|
49 | void writeDecay(Event& event, vector<HelicityParticle>& p); |
---|
50 | |
---|
51 | private: |
---|
52 | |
---|
53 | // Constants: could only be changed in the code itself. |
---|
54 | static const int NTRYCHANNEL, NTRYDECAY; |
---|
55 | static const double WTCORRECTION[11]; |
---|
56 | |
---|
57 | // Flag whether a correlated tau decay should be performed. |
---|
58 | bool correlated; |
---|
59 | |
---|
60 | // User selected mode and mother for tau decays. |
---|
61 | int tauMode, tauMother, tauModeSave, tauMotherSave; |
---|
62 | |
---|
63 | // User selected polarization for tau decays. |
---|
64 | double polarization, polSave; |
---|
65 | |
---|
66 | // Helicity matrix element pointers. |
---|
67 | HelicityMatrixElement* hardME; |
---|
68 | HelicityMatrixElement* decayME; |
---|
69 | |
---|
70 | // Hard process helicity matrix elements. |
---|
71 | HMETwoFermions2W2TwoFermions hmeTwoFermions2W2TwoFermions; |
---|
72 | HMETwoFermions2Z2TwoFermions hmeTwoFermions2Z2TwoFermions; |
---|
73 | HMETwoFermions2Gamma2TwoFermions hmeTwoFermions2Gamma2TwoFermions; |
---|
74 | HMETwoFermions2GammaZ2TwoFermions hmeTwoFermions2GammaZ2TwoFermions; |
---|
75 | HMEZ2TwoFermions hmeZ2TwoFermions; |
---|
76 | HMEHiggsEven2TwoFermions hmeHiggsEven2TwoFermions; |
---|
77 | HMEHiggsOdd2TwoFermions hmeHiggsOdd2TwoFermions; |
---|
78 | HMEHiggsCharged2TwoFermions hmeHiggsCharged2TwoFermions; |
---|
79 | HMEUnpolarized hmeUnpolarized; |
---|
80 | |
---|
81 | // Tau decay helicity matrix elements. |
---|
82 | HMETau2Meson hmeTau2Meson; |
---|
83 | HMETau2TwoLeptons hmeTau2TwoLeptons; |
---|
84 | HMETau2TwoMesonsViaVector hmeTau2TwoMesonsViaVector; |
---|
85 | HMETau2TwoMesonsViaVectorScalar hmeTau2TwoMesonsViaVectorScalar; |
---|
86 | HMETau2ThreePions hmeTau2ThreePions; |
---|
87 | HMETau2ThreeMesonsWithKaons hmeTau2ThreeMesonsWithKaons; |
---|
88 | HMETau2ThreeMesonsGeneric hmeTau2ThreeMesonsGeneric; |
---|
89 | HMETau2TwoPionsGamma hmeTau2TwoPionsGamma; |
---|
90 | HMETau2FourPions hmeTau2FourPions; |
---|
91 | HMETau2FivePions hmeTau2FivePions; |
---|
92 | HMETau2PhaseSpace hmeTau2PhaseSpace; |
---|
93 | |
---|
94 | // Particles of the hard process. |
---|
95 | HelicityParticle in1, in2, mediator, out1, out2; |
---|
96 | vector<HelicityParticle> particles; |
---|
97 | |
---|
98 | // The info pointer for the Pythia class. |
---|
99 | Info* infoPtr; |
---|
100 | |
---|
101 | // Pointer to settings database. |
---|
102 | Settings* settingsPtr; |
---|
103 | |
---|
104 | // Pointer to the particle data table. |
---|
105 | ParticleData* particleDataPtr; |
---|
106 | |
---|
107 | // Pointer to the random number generator. |
---|
108 | Rndm* rndmPtr; |
---|
109 | |
---|
110 | // Pointer to SM coupling data. |
---|
111 | Couplings* couplingsPtr; |
---|
112 | |
---|
113 | }; |
---|
114 | |
---|
115 | //========================================================================== |
---|
116 | |
---|
117 | } // end namespace Pythia8 |
---|
118 | |
---|
119 | #endif // end Pythia8_TauDecays_H |
---|