1 //--------------------------------------------------------------------------
4 // This software is part of the EvtGen package developed jointly
5 // for the BaBar and CLEO collaborations. If you use all or part
6 // of it, please give an appropriate acknowledgement.
8 // Copyright Information: See EvtGen/COPYRIGHT
9 // Copyright (C) 1998 Caltech, UCSB
11 // Module: EvtTaulnunu.cc
13 // Description: The leptonic decay of the tau meson.
14 // E.g., tau- -> e- nueb nut
16 // Modification history:
18 // RYD January 17, 1997 Module created
20 //------------------------------------------------------------------------
22 #include "EvtGenBase/EvtPatches.hh"
26 #include "EvtGenBase/EvtParticle.hh"
27 #include "EvtGenBase/EvtPDL.hh"
28 #include "EvtGenBase/EvtGenKine.hh"
29 #include "EvtGenModels/EvtTaulnunu.hh"
30 #include "EvtGenBase/EvtDiracSpinor.hh"
31 #include "EvtGenBase/EvtReport.hh"
32 #include "EvtGenBase/EvtVector4C.hh"
34 EvtTaulnunu::~EvtTaulnunu() {}
36 std::string EvtTaulnunu::getName(){
43 EvtDecayBase* EvtTaulnunu::clone(){
45 return new EvtTaulnunu;
49 void EvtTaulnunu::init(){
51 // check that there are 0 arguments
55 checkSpinParent(EvtSpinType::DIRAC);
57 checkSpinDaughter(0,EvtSpinType::DIRAC);
58 checkSpinDaughter(1,EvtSpinType::NEUTRINO);
59 checkSpinDaughter(2,EvtSpinType::NEUTRINO);
63 void EvtTaulnunu::initProbMax(){
69 void EvtTaulnunu::decay(EvtParticle *p){
70 static EvtId TAUM=EvtPDL::getId("tau-");
72 p->initializePhaseSpace(getNDaug(),getDaugs());
74 EvtParticle *l, *nul, *nut;
80 EvtVector4C l1, l2, tau1, tau2;
82 if (p->getId()==TAUM) {
84 tau1=EvtLeptonVACurrent(nut->spParentNeutrino(),p->sp(0));
85 tau2=EvtLeptonVACurrent(nut->spParentNeutrino(),p->sp(1));
86 l1=EvtLeptonVACurrent(l->spParent(0),nul->spParentNeutrino());
87 l2=EvtLeptonVACurrent(l->spParent(1),nul->spParentNeutrino());
91 tau1=EvtLeptonVACurrent(p->sp(0),nut->spParentNeutrino());
92 tau2=EvtLeptonVACurrent(p->sp(1),nut->spParentNeutrino());
93 l1=EvtLeptonVACurrent(nul->spParentNeutrino(),l->spParent(0));
94 l2=EvtLeptonVACurrent(nul->spParentNeutrino(),l->spParent(1));