Page MenuHomeHEPForge
Files F7878223

No OneTemporary
Actions

View Options

diff --git a/Helicity/Vertex/Vector/GeneralFFVVertex.cc b/Helicity/Vertex/Vector/GeneralFFVVertex.cc
--- a/Helicity/Vertex/Vector/GeneralFFVVertex.cc
+++ b/Helicity/Vertex/Vector/GeneralFFVVertex.cc
@@ -1,342 +1,353 @@
// -*- C++ -*-
//
// GeneralFFVVertex.cc is a part of ThePEG - Toolkit for HEP Event Generation
// Copyright (C) 2003-2011 Peter Richardson, Leif Lonnblad
//
// ThePEG is licenced under version 2 of the GPL, see COPYING for details.
// Please respect the MCnet academic guidelines, see GUIDELINES for details.
//
//
// This is the implementation of the non-inlined, non-templated member
// functions of the GeneralFFVVertex class.
//
#include "GeneralFFVVertex.h"
#include "ThePEG/Interface/ClassDocumentation.h"
#include "ThePEG/Persistency/PersistentOStream.h"
#include "ThePEG/Persistency/PersistentIStream.h"
+#include "ThePEG/Helicity/LorentzTensor.h"
using namespace ThePEG;
using namespace Helicity;
// Definition of the static class description member
AbstractNoPIOClassDescription<GeneralFFVVertex> GeneralFFVVertex::initGeneralFFVVertex;
void GeneralFFVVertex::Init() {
static ClassDocumentation<GeneralFFVVertex> documentation
("The GeneralFFVVertex class implements the helicity amplitude"
"calculations for a fermion-fantifermion gauge boson vertex. Any "
"implementation of such a vertex should inherit from in and implement"
" the virtual setCoupling member to calculate the coupling");
}
// evalulate the full vertex
Complex GeneralFFVVertex::evaluate(Energy2 q2,
const SpinorWaveFunction & sp,
const SpinorBarWaveFunction & sbar,
const VectorWaveFunction & vec) {
+
+
+ //LorentzTensor<double> test = sp.wave().sigma(sbar.wave());
+ LorentzSpinor<SqrtEnergy> spWave = sp.dimensionedWave();
+ LorentzSpinorBar<SqrtEnergy> sbarWave = sbar.dimensionedWave();
+ LorentzTensor<QTY<0,2,0,1,2,1>::Type > test(spWave.sigma(sbarWave));
+ LorentzTensor<QTY<0,2,0,1,2,1>::Type > test2(spWave.sigma(sbarWave));
+
+ complex<Energy2> prod = test*test2;
+
// first calculate the couplings
setCoupling(q2,sp.particle(),sbar.particle(),vec.particle());
Complex ii(0.,1.);
// useful combinations of the polarization vector components
Complex e0p3=vec.t()+vec.z();
Complex e0m3=vec.t()-vec.z();
Complex e1p2=vec.x()+ii*vec.y();
Complex e1m2=vec.x()-ii*vec.y();
complex<Energy> p0p3=vec. e()+vec.pz();
complex<Energy> p0m3=vec. e()-vec.pz();
complex<Energy> p1p2=vec.px()+ii*vec.py();
complex<Energy> p1m2=vec.px()-ii*vec.py();
// get both the spinors in the same representation (using the default choice)
Complex vertex(0.);
// first the left piece as this is virtually always needed
if(_left!=0.) {
vertex = _left*(+sbar.s3()*(sp.s1()*e0p3+sp.s2()*e1m2)
+sbar.s4()*(sp.s1()*e1p2+sp.s2()*e0m3));
}
// then the right piece (often not needed eg W vertex)
if(_right!=0.) {
vertex += _right*(+sbar.s1()*(sp.s3()*e0m3-sp.s4()*e1m2)
-sbar.s2()*(sp.s3()*e1p2-sp.s4()*e0p3));
}
// left sigma piece
if(_leftSigma!=0./GeV) {
vertex += -ii * _leftSigma *
(sbar.s1()*sp.s1()*(-vec. e()*vec.z() + vec.pz()*vec.t()
-ii*(vec.py()*vec.x()-vec.px()*vec.y()))+
sbar.s2()*sp.s1()*( p1p2*e0p3 - p0p3*e1p2 ) +
sbar.s1()*sp.s2()*( + p1m2*e0m3 - p0m3*e1m2 ) +
sbar.s2()*sp.s2()*( vec. e()*vec.z() - vec.pz()*vec.t()
-ii*(vec.px()*vec.y()-vec.py()*vec.x())));
}
// right sigma piece
if(_rightSigma!=0./GeV) {
vertex += ii * _rightSigma *
(sbar.s3()*sp.s3()*(-vec.e()*vec.z()+vec.pz()*vec.t()
-ii*(vec.px()*vec.y()-vec.py()*vec.x()))+
sbar.s4()*sp.s3()*( p1p2*e0m3 - p0m3*e1p2 ) +
sbar.s3()*sp.s4()*( p1m2*e0p3 - p0p3*e1m2 ) +
sbar.s4()*sp.s4()*( vec.e()*vec.z()-vec.pz()*vec.t()
+ii*(vec.px()*vec.y()-vec.py()*vec.x())));
}
vertex *= ii;
// final factors
return vertex*norm();
}
// evaluate an off-shell spinor
SpinorWaveFunction GeneralFFVVertex::evaluate(Energy2 q2, int iopt,tcPDPtr out,
const SpinorWaveFunction & sp,
const VectorWaveFunction &vec,
complex<Energy> mass,
complex<Energy> width) {
// extract the pointers to the particle data objects
tcPDPtr Psp=sp.particle();
tcPDPtr Pvec=vec.particle();
// first calculate the couplings
setCoupling(q2,Psp,out,Pvec);
Complex ii(0.,1.);
// work out the momentum of the off-shell particle
Lorentz5Momentum pout = sp.momentum()+vec.momentum();
// now evaluate the contribution
// polarization components
Complex e0p3 = vec.t() + vec.z();
Complex e0m3 = vec.t() - vec.z();
Complex e1p2 = vec.x()+ii*vec.y();
Complex e1m2 = vec.x()-ii*vec.y();
// overall factor
Energy2 p2 = pout.m2();
Complex fact=-normPropagator(iopt,p2,out,mass,width);
// momentum components
if(mass.real() < ZERO) mass = iopt==5 ? ZERO : out->mass();
complex<Energy> p0p3 = pout.e() + pout.z();
complex<Energy> p0m3 = pout.e() - pout.z();
complex<Energy> p1p2 = pout.x() + ii*pout.y();
complex<Energy> p1m2 = pout.x() - ii*pout.y();
// complex nos for for the spinor
Complex s1(0.),s2(0.),s3(0.),s4(0.);
Complex a1 = fact*( sp.s3()*e0m3-sp.s4()*e1m2);
Complex a2 = fact*(-sp.s3()*e1p2+sp.s4()*e0p3);
Complex a3 = fact*( sp.s1()*e0p3+sp.s2()*e1m2);
Complex a4 = fact*( sp.s1()*e1p2+sp.s2()*e0m3);
// left piece
if(_left!=0.) {
s1 +=UnitRemoval::InvE * _left * (p0m3*a3-p1m2*a4);
s2 +=UnitRemoval::InvE * _left * (-p1p2*a3+p0p3*a4);
s3 +=UnitRemoval::InvE * _left * a3*mass;
s4 +=UnitRemoval::InvE * _left * a4*mass;
}
// right piece
if(_right!=0.) {
s1 +=UnitRemoval::InvE * _right * a1*mass;
s2 +=UnitRemoval::InvE * _right * a2*mass;
s3 +=UnitRemoval::InvE * _right * (p0p3*a1+p1m2*a2);
s4 +=UnitRemoval::InvE * _right * (p1p2*a1+p0m3*a2);
}
complex<Energy> p0p3b = vec. e() + vec.pz();
complex<Energy> p0m3b = vec. e() - vec.pz();
complex<Energy> p1p2b = vec.px() + ii*vec.py();
complex<Energy> p1m2b = vec.px() - ii*vec.py();
complex<Energy> b1 = fact*( sp.s3()*p0m3b - sp.s4()*p1m2b);
complex<Energy> b2 = fact*(-sp.s3()*p1p2b + sp.s4()*p0p3b);
complex<Energy> b3 = fact*( sp.s1()*p0p3b + sp.s2()*p1m2b);
complex<Energy> b4 = fact*( sp.s1()*p1p2b + sp.s2()*p0m3b);
// left sigma piece
if(_leftSigma!=0./GeV) {
s1 += -0.5*ii*UnitRemoval::InvE *mass*_leftSigma*
( - a3*p0m3b + a4*p1m2b + b3*e0m3 - b4*e1m2);
s2 += 0.5*ii*UnitRemoval::InvE *mass*_leftSigma*
( - a3*p1p2b + a4*p0p3b + b3*e1p2 - b4*e0p3);
s3 += -0.5*ii*UnitRemoval::InvE*_leftSigma*
( + p0p3*( - a3*p0m3b + a4*p1m2b + b3*e0m3 - b4*e1m2 )
+ p1m2*( a3*p1p2b - a4*p0p3b - b3*e1p2 + b4*e0p3 ) );
s4 += 0.5*ii*UnitRemoval::InvE*_leftSigma*
( + p1p2*( + a3*p0m3b - a4*p1m2b - b3*e0m3 + b4*e1m2 )
+ p0m3*( - a3*p1p2b + a4*p0p3b + b3*e1p2 - b4*e0p3 ) );
}
// right sigma piece
if(_rightSigma!=0./GeV) {
s1 += 0.5*ii*UnitRemoval::InvE *_rightSigma*
( + p0m3*( + a1*p0p3b + a2*p1m2b - b1*e0p3 - b2*e1m2 )
+ p1m2*( - a1*p1p2b - a2*p0m3b + b1*e1p2 + b2*e0m3 ) );
s2 += -0.5*ii*UnitRemoval::InvE *_rightSigma*
( + p1p2*( + a1*p0p3b + a2*p1m2b - b1*e0p3 - b2*e1m2 )
+ p0p3*( - a1*p1p2b - a2*p0m3b + b1*e1p2 + b2*e0m3 ) );
s3 += 0.5*ii*UnitRemoval::InvE *mass*_rightSigma*
( a1*p0p3b + a2*p1m2b - b1*e0p3 - b2*e1m2 );
s4 += -0.5*ii*UnitRemoval::InvE *mass*_rightSigma*
( -a1*p1p2b - a2*p0m3b + b2*e0m3 + b1*e1p2 );
}
// return the wavefunction
return SpinorWaveFunction(pout,out,s1,s2,s3,s4);
}
// evaluate an off-shell SpinorBar
SpinorBarWaveFunction GeneralFFVVertex::evaluate(Energy2 q2,int iopt,tcPDPtr out,
const SpinorBarWaveFunction & sbar,
const VectorWaveFunction & vec,
complex<Energy> mass,
complex<Energy> width) {
// first calculate the couplings
setCoupling(q2,out,sbar.particle(),vec.particle());
Complex ii(0.,1.);
// work out the momentum of the off-shell particle
Lorentz5Momentum pout = sbar.momentum()+vec.momentum();
// now evaluate the contribution
// polarization components
Complex e0p3=vec.t() + vec.z();
Complex e0m3=vec.t() - vec.z();
Complex e1p2=vec.x()+ii*vec.y();
Complex e1m2=vec.x()-ii*vec.y();
// overall factor
Energy2 p2 = pout.m2();
Complex fact=-normPropagator(iopt,p2,out,mass,width);
// momentum components
if(mass.real() < ZERO) mass = (iopt==5) ? ZERO : out->mass();
complex<Energy> p1p2=pout.x() + ii*pout.y();
complex<Energy> p1m2=pout.x() - ii*pout.y();
complex<Energy> p0p3=pout.e() + pout.z();
complex<Energy> p0m3=pout.e() - pout.z();
// complex numbers for the spinor
Complex s1(0.),s2(0.),s3(0.),s4(0.);
Complex a1 = fact*( sbar.s3()*e0p3+sbar.s4()*e1p2);
Complex a2 = fact*( sbar.s3()*e1m2+sbar.s4()*e0m3);
Complex a3 = fact*( sbar.s1()*e0m3-sbar.s2()*e1p2);
Complex a4 = fact*(-sbar.s1()*e1m2+sbar.s2()*e0p3);
complex<Energy> p0p3b = vec. e() + vec.pz();
complex<Energy> p0m3b = vec. e() - vec.pz();
complex<Energy> p1p2b = vec.px() + ii*vec.py();
complex<Energy> p1m2b = vec.px() - ii*vec.py();
complex<Energy> b1 = fact*( sbar.s3()*p0p3b+sbar.s4()*p1p2b);
complex<Energy> b2 = fact*( sbar.s3()*p1m2b+sbar.s4()*p0m3b);
complex<Energy> b3 = fact*( sbar.s1()*p0m3b-sbar.s2()*p1p2b);
complex<Energy> b4 = fact*(-sbar.s1()*p1m2b+sbar.s2()*p0p3b);
// left piece
if(_left!=0.) {
s1 += UnitRemoval::InvE*_left*a1*mass;
s2 += UnitRemoval::InvE*_left*a2*mass;
s3 += UnitRemoval::InvE*_left*(-p0m3*a1+p1p2*a2);
s4 += UnitRemoval::InvE*_left*(+p1m2*a1-p0p3*a2);
}
// right piece
if(_right!=0.) {
s1 += UnitRemoval::InvE*_right*(-p0p3*a3-p1p2*a4);
s2 += UnitRemoval::InvE*_right*(-p1m2*a3-p0m3*a4);
s3 += UnitRemoval::InvE*_right*a3*mass;
s4 += UnitRemoval::InvE*_right*a4*mass;
}
// left sigma piece
if(_leftSigma!=0./GeV) {
s1 += 0.5*ii*UnitRemoval::InvE*_leftSigma*mass*
( + a3*p0p3b + a4*p1p2b - b3*e0p3 - b4*e1p2);
s2 += -0.5*ii*UnitRemoval::InvE*_leftSigma*mass*
( - a3*p1m2b - a4*p0m3b + b3*e1m2 + b4*e0m3);
s3 += -0.5*ii*UnitRemoval::InvE*_leftSigma*
(+p0m3*( + a3*p0p3b + a4*p1p2b - b3*e0p3 - b4*e1p2)
+p1p2*( - a3*p1m2b - a4*p0m3b + b3*e1m2 + b4*e0m3));
s4 += +0.5*ii*UnitRemoval::InvE*_leftSigma*
(+p1m2*( + a3*p0p3b + a4*p1p2b - b3*e0p3 - b4*e1p2)
+p0p3*( - a3*p1m2b - a4*p0m3b + b3*e1m2 + b4*e0m3));
}
// right sigma piece
if(_rightSigma!=0./GeV) {
s1 += +0.5*ii*UnitRemoval::InvE*_rightSigma*
(+p0p3*( - a1*p0m3b + a2*p1p2b + b1*e0m3 - b2*e1p2)
+p1p2*( + a1*p1m2b - a2*p0p3b - b1*e1m2 + b2*e0p3));
s2 += -0.5*ii*UnitRemoval::InvE*_rightSigma*
(+p1m2*( + a1*p0m3b - a2*p1p2b - b1*e0m3 + b2*e1p2)
+p0m3*( - a1*p1m2b + a2*p0p3b + b1*e1m2 - b2*e0p3));
s3 += -0.5*ii*UnitRemoval::InvE*_rightSigma*mass*
( - a1*p0m3b + a2*p1p2b + b1*e0m3 - b2*e1p2 );
s4 += 0.5*ii*UnitRemoval::InvE*_rightSigma*mass*
( - a1*p1m2b + a2*p0p3b + b1*e1m2 - b2*e0p3 );
}
return SpinorBarWaveFunction(pout,out,s1,s2,s3,s4);
}
// off-shell vector
VectorWaveFunction GeneralFFVVertex::evaluate(Energy2 q2,int iopt,tcPDPtr out,
const SpinorWaveFunction & sp,
const SpinorBarWaveFunction & sbar,
complex<Energy> mass,
complex<Energy> width) {
// first calculate the couplings
setCoupling(q2,sp.particle(),sbar.particle(),out);
Complex ii(0.,1.);
// work out the momentum of the off-shell particle
Lorentz5Momentum pout = sbar.momentum()+sp.momentum();
// overall factor
Energy2 p2 = pout.m2();
Complex fact = normPropagator(iopt,p2,out,mass,width);
// momentum components
if(mass.real() < ZERO) mass = (iopt==5) ? ZERO : out->mass();
complex<Energy2> mass2 = sqr(mass);
// the vector for the fermion-antifermion
Complex vec[4];
complex<Energy> p1p2=pout.x() + ii*pout.y();
complex<Energy> p1m2=pout.x() - ii*pout.y();
complex<Energy> p0p3=pout.e() + pout.z();
complex<Energy> p0m3=pout.e() - pout.z();
// left coupling
if(_left!=0.) {
vec[0] = -_left*(sbar.s3()*sp.s2()+sbar.s4()*sp.s1());
vec[1] = ii*_left*(sbar.s3()*sp.s2()-sbar.s4()*sp.s1());
vec[2] = -_left*(sbar.s3()*sp.s1()-sbar.s4()*sp.s2());
vec[3] = _left*(sbar.s3()*sp.s1()+sbar.s4()*sp.s2());
}
// right coupling
if(_right!=0.) {
vec[0] += +_right*(sbar.s1()*sp.s4()+sbar.s2()*sp.s3());
vec[1] += -ii*_right*(sbar.s1()*sp.s4()-sbar.s2()*sp.s3());
vec[2] += +_right*(sbar.s1()*sp.s3()-sbar.s2()*sp.s4());
vec[3] += +_right*(sbar.s1()*sp.s3()+sbar.s2()*sp.s4());
}
// left sigma
if(_leftSigma==0./GeV) {
vec[0] += -0.5*ii*_leftSigma*
(+sp.s1()*sbar.s1()*(p1p2-p1m2)+2.*sp.s1()*sbar.s2()*p0p3
-sp.s2()*sbar.s2()*(p1p2-p1m2)+2.*sp.s2()*sbar.s1()*p0m3);
vec[1] += -0.5 *_leftSigma*
(+sp.s1()*sbar.s1()*(p1m2-p1p2)+2.*sp.s1()*sbar.s2()*p0p3
+sp.s2()*sbar.s2()*(p1p2+p1m2)-2.*sp.s2()*sbar.s1()*p0m3);
vec[2] += -0.5*ii*_leftSigma*
(+sp.s1()*sbar.s1()*(p0p3+p0m3)-2.*sp.s1()*sbar.s2()*p1p2
-sp.s2()*sbar.s2()*(p0p3+p0m3)+2.*sp.s2()*sbar.s1()*p1m2);
vec[3] += 0.5*ii*_leftSigma*
(-sp.s1()*sbar.s1()*(p0p3-p0m3)-2.*sp.s1()*sbar.s2()*p1p2
+sp.s2()*sbar.s2()*(p0p3-p0m3)-2.*sp.s2()*sbar.s1()*p1m2);
}
// right sigma
if(_rightSigma==0./GeV) {
vec[0] += 0.5*ii*_rightSigma*
(-sp.s3()*sbar.s3()*(p1p2-p1m2)+2.*sp.s3()*sbar.s4()*p0m3
+sp.s4()*sbar.s4()*(p1p2-p1m2)+2.*sp.s4()*sbar.s3()*p0p3);
vec[1] += 0.5* _rightSigma*
(-sp.s3()*sbar.s3()*(p1p2+p1m2)-2.*sp.s3()*sbar.s4()*p0m3
+sp.s4()*sbar.s4()*(p1p2+p1m2)+2.*sp.s4()*sbar.s3()*p0p3);
vec[2] += 0.5*ii*_rightSigma*
(+sp.s3()*sbar.s3()*(p0p3+p0m3)+2.*sp.s3()*sbar.s4()*p1p2
-sp.s4()*sbar.s4()*(p0p3+p0m3)-2.*sp.s4()*sbar.s3()*p1m2);
vec[3] += -0.5*ii*_rightSigma*
(-sp.s3()*sbar.s3()*(p0p3-p0m3)-2.*sp.s3()*sbar.s4()*p1p2
+sp.s4()*sbar.s4()*(p0p3-p0m3)-2.*sp.s4()*sbar.s3()*p1m2);
}
// massless boson
if(mass.real()==ZERO) {
for(int ix=0;ix<4;++ix){vec[ix]*=fact;}
}
// massive boson
else {
complex<InvEnergy> dot = ( pout.e() *vec[3]
-pout.x()*vec[0]
-pout.y()*vec[1]
-pout.z()*vec[2])/mass2;
vec[0]=fact*(vec[0]-dot*pout.x());
vec[1]=fact*(vec[1]-dot*pout.y());
vec[2]=fact*(vec[2]-dot*pout.z());
vec[3]=fact*(vec[3]-dot*pout.e());
}
return VectorWaveFunction(pout,out,vec[0],vec[1],vec[2],vec[3]);
}

File Metadata

Mime Type
text/x-diff
Expires
Tue, Nov 19, 5:25 PM (1 d, 12 h)
Storage Engine
blob
Storage Format
Raw Data
Storage Handle
3805382
Default Alt Text
(14 KB)

Event Timeline