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: EvtSemiLeptonicBaryonAmp.cc
13 // Description: Routine to implement semileptonic decays to vector
16 // Modification history:
18 // Lange Oct 20, 2004 Module created.
20 //------------------------------------------------------------------------
22 #include "EvtGenBase/EvtPatches.hh"
23 #include "EvtGenBase/EvtPatches.hh"
24 #include "EvtGenBase/EvtParticle.hh"
25 #include "EvtGenBase/EvtGenKine.hh"
26 #include "EvtGenBase/EvtPDL.hh"
27 #include "EvtGenBase/EvtReport.hh"
28 #include "EvtGenBase/EvtTensor4C.hh"
29 #include "EvtGenBase/EvtVector4C.hh"
30 #include "EvtGenBase/EvtDiracSpinor.hh"
31 #include "EvtGenBase/EvtSemiLeptonicBaryonAmp.hh"
32 #include "EvtGenBase/EvtId.hh"
33 #include "EvtGenBase/EvtAmp.hh"
34 #include "EvtGenBase/EvtSemiLeptonicFF.hh"
35 #include "EvtGenBase/EvtGammaMatrix.hh"
38 void EvtSemiLeptonicBaryonAmp::CalcAmp( EvtParticle *parent,
40 EvtSemiLeptonicFF *FormFactors ) {
42 static EvtId EM=EvtPDL::getId("e-");
43 static EvtId MUM=EvtPDL::getId("mu-");
44 static EvtId TAUM=EvtPDL::getId("tau-");
45 static EvtId EP=EvtPDL::getId("e+");
46 static EvtId MUP=EvtPDL::getId("mu+");
47 static EvtId TAUP=EvtPDL::getId("tau+");
50 //Add the lepton and neutrino 4 momenta to find q2
52 EvtVector4R q = parent->getDaug(1)->getP4()
53 + parent->getDaug(2)->getP4();
54 double q2 = (q.mass2());
56 double f1v,f1a,f2v,f2a;
57 double m_meson = parent->getDaug(0)->mass();
59 FormFactors->getbaryonff(parent->getId(),
60 parent->getDaug(0)->getId(),
69 p4b.set(parent->mass(),0.0,0.0,0.0);
71 EvtVector4C temp_00_term1;
72 EvtVector4C temp_00_term2;
74 EvtVector4C temp_01_term1;
75 EvtVector4C temp_01_term2;
77 EvtVector4C temp_10_term1;
78 EvtVector4C temp_10_term2;
80 EvtVector4C temp_11_term1;
81 EvtVector4C temp_11_term2;
83 EvtDiracSpinor p0=parent->sp(0);
84 EvtDiracSpinor p1=parent->sp(1);
86 EvtDiracSpinor d0=parent->getDaug(0)->spParent(0);
87 EvtDiracSpinor d1=parent->getDaug(0)->spParent(1);
89 temp_00_term1.set(0,f1v*(d0*(EvtGammaMatrix::g0()*p0)));
90 temp_00_term2.set(0,f1a*(d0*((EvtGammaMatrix::g0()*EvtGammaMatrix::g5())*p0)));
91 temp_01_term1.set(0,f1v*(d0*(EvtGammaMatrix::g0()*p1)));
92 temp_01_term2.set(0,f1a*(d0*((EvtGammaMatrix::g0()*EvtGammaMatrix::g5())*p1)));
93 temp_10_term1.set(0,f1v*(d1*(EvtGammaMatrix::g0()*p0)));
94 temp_10_term2.set(0,f1a*(d1*((EvtGammaMatrix::g0()*EvtGammaMatrix::g5())*p0)));
95 temp_11_term1.set(0,f1v*(d1*(EvtGammaMatrix::g0()*p1)));
96 temp_11_term2.set(0,f1a*(d1*((EvtGammaMatrix::g0()*EvtGammaMatrix::g5())*p1)));
98 temp_00_term1.set(1,f1v*(d0*(EvtGammaMatrix::g1()*p0)));
99 temp_00_term2.set(1,f1a*(d0*((EvtGammaMatrix::g1()*EvtGammaMatrix::g5())*p0)));
100 temp_01_term1.set(1,f1v*(d0*(EvtGammaMatrix::g1()*p1)));
101 temp_01_term2.set(1,f1a*(d0*((EvtGammaMatrix::g1()*EvtGammaMatrix::g5())*p1)));
102 temp_10_term1.set(1,f1v*(d1*(EvtGammaMatrix::g1()*p0)));
103 temp_10_term2.set(1,f1a*(d1*((EvtGammaMatrix::g1()*EvtGammaMatrix::g5())*p0)));
104 temp_11_term1.set(1,f1v*(d1*(EvtGammaMatrix::g1()*p1)));
105 temp_11_term2.set(1,f1a*(d1*((EvtGammaMatrix::g1()*EvtGammaMatrix::g5())*p1)));
107 temp_00_term1.set(2,f1v*(d0*(EvtGammaMatrix::g2()*p0)));
108 temp_00_term2.set(2,f1a*(d0*((EvtGammaMatrix::g2()*EvtGammaMatrix::g5())*p0)));
109 temp_01_term1.set(2,f1v*(d0*(EvtGammaMatrix::g2()*p1)));
110 temp_01_term2.set(2,f1a*(d0*((EvtGammaMatrix::g2()*EvtGammaMatrix::g5())*p1)));
111 temp_10_term1.set(2,f1v*(d1*(EvtGammaMatrix::g2()*p0)));
112 temp_10_term2.set(2,f1a*(d1*((EvtGammaMatrix::g2()*EvtGammaMatrix::g5())*p0)));
113 temp_11_term1.set(2,f1v*(d1*(EvtGammaMatrix::g2()*p1)));
114 temp_11_term2.set(2,f1a*(d1*((EvtGammaMatrix::g2()*EvtGammaMatrix::g5())*p1)));
116 temp_00_term1.set(3,f1v*(d0*(EvtGammaMatrix::g3()*p0)));
117 temp_00_term2.set(3,f1a*(d0*((EvtGammaMatrix::g3()*EvtGammaMatrix::g5())*p0)));
118 temp_01_term1.set(3,f1v*(d0*(EvtGammaMatrix::g3()*p1)));
119 temp_01_term2.set(3,f1a*(d0*((EvtGammaMatrix::g3()*EvtGammaMatrix::g5())*p1)));
120 temp_10_term1.set(3,f1v*(d1*(EvtGammaMatrix::g3()*p0)));
121 temp_10_term2.set(3,f1a*(d1*((EvtGammaMatrix::g3()*EvtGammaMatrix::g5())*p0)));
122 temp_11_term1.set(3,f1v*(d1*(EvtGammaMatrix::g3()*p1)));
123 temp_11_term2.set(3,f1a*(d1*((EvtGammaMatrix::g3()*EvtGammaMatrix::g5())*p1)));
129 EvtId l_num = parent->getDaug(1)->getId();
130 if (l_num==EM||l_num==MUM||l_num==TAUM){
132 l1=EvtLeptonVACurrent(parent->getDaug(1)->spParent(0),
133 parent->getDaug(2)->spParentNeutrino());
134 l2=EvtLeptonVACurrent(parent->getDaug(1)->spParent(1),
135 parent->getDaug(2)->spParentNeutrino());
138 if (l_num==EP||l_num==MUP||l_num==TAUP){
139 l1=EvtLeptonVACurrent(parent->getDaug(2)->spParentNeutrino(),
140 parent->getDaug(1)->spParent(0));
141 l2=EvtLeptonVACurrent(parent->getDaug(2)->spParentNeutrino(),
142 parent->getDaug(1)->spParent(1));
145 report(ERROR,"EvtGen") << "Wrong lepton number"<<endl;
149 amp.vertex(0,0,0,l1.cont(temp_00_term1+temp_00_term2));
150 amp.vertex(0,0,1,l2.cont(temp_00_term1+temp_00_term2));
152 amp.vertex(0,1,0,l1.cont(temp_01_term1+temp_01_term2));
153 amp.vertex(0,1,1,l2.cont(temp_01_term1+temp_01_term2));
155 amp.vertex(1,0,0,l1.cont(temp_10_term1+temp_10_term2));
156 amp.vertex(1,0,1,l2.cont(temp_10_term1+temp_10_term2));
158 amp.vertex(1,1,0,l1.cont(temp_11_term1+temp_11_term2));
159 amp.vertex(1,1,1,l2.cont(temp_11_term1+temp_11_term2));