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
13 // Description: The decay Vector -> Vector gamma
14 // E.g., CHI1->PSI GAMMA
16 // Modification history:
18 // RYD September 5, 1997 Module created
20 //------------------------------------------------------------------------
22 #include "EvtGenBase/EvtPatches.hh"
26 #include "EvtGenBase/EvtVector3C.hh"
27 #include "EvtGenBase/EvtParticle.hh"
28 #include "EvtGenBase/EvtPDL.hh"
29 #include "EvtGenBase/EvtGenKine.hh"
30 #include "EvtGenBase/EvtVector4C.hh"
31 #include "EvtGenModels/EvtVVP.hh"
32 #include "EvtGenBase/EvtReport.hh"
36 std::string EvtVVP::getName(){
43 EvtDecayBase* EvtVVP::clone(){
51 // check that there are 8 arguments
56 checkSpinParent(EvtSpinType::VECTOR);
57 checkSpinDaughter(0,EvtSpinType::VECTOR);
58 checkSpinDaughter(1,EvtSpinType::PHOTON);
61 void EvtVVP::initProbMax(){
67 void EvtVVP::decay(EvtParticle *p){
69 p->initializePhaseSpace(getNDaug(),getDaugs());
80 epsp[0]=p->eps(0).vec();
81 epsp[1]=p->eps(1).vec();
82 epsp[2]=p->eps(2).vec();
84 epsv[0]=v->eps(0).vec().conj();
85 epsv[1]=v->eps(1).vec().conj();
86 epsv[2]=v->eps(2).vec().conj();
88 epsph[0]=ph->epsParentPhoton(0).vec().conj();
89 epsph[1]=ph->epsParentPhoton(1).vec().conj();
95 vertex(i,j,k,epsp[i].cross(epsv[j])*epsph[k]);