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50.9.3
by Johan Alwall
Added Template and HELAS into bzr |
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subroutine t2xxxx(p,tmass,nhel,nst ,ft) |
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c
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c This subroutine computes k^mu*e^nu where e is delta(i,nhel).
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c It is used to test for gauge invariance of the tensor routines.
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c
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c input:
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c real p(0:3) : four-momentum of tensor boson
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c real tmass : mass of tensor boson
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c integer nhel = =-2..2 : construction of e^nu
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c integer nst = -1 or 1 : +1 for final, -1 for initial
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c
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c output:
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c complex tc(6,4) : tensor wavefunction epsilon^mu^nu(t)
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c
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implicit none |
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double complex ft(18),tc(6,4), ep(4), em(4) |
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double precision p(0:3), tmass |
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integer nhel, nst, i, j |
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double precision rZero, rOne |
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parameter( rZero = 0.0d0, rOne = 1.0d0 ) |
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c
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tc(5,1) = dcmplx(p(0),p(3))*nst |
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tc(6,1) = dcmplx(p(1),p(2))*nst |
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ep(1) = dcmplx( p(0), rZero ) |
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ep(2) = dcmplx( p(1), rZero ) |
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ep(3) = dcmplx( p(2), rZero ) |
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ep(4) = dcmplx( p(3), rZero ) |
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if ( nhel.eq.1 ) then |
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em(1) = dcmplx( rOne , rZero ) |
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em(2) = dcmplx( rZero, rZero ) |
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em(3) = dcmplx( rZero, rZero ) |
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em(4) = dcmplx( rZero, rZero ) |
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else if ( nhel.eq.-1 ) then |
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em(1) = dcmplx( rZero, rZero ) |
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em(2) = dcmplx( rOne , rZero ) |
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em(3) = dcmplx( rZero, rZero ) |
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em(4) = dcmplx( rZero, rZero ) |
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else if ( nhel.eq.2 ) then |
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em(1) = dcmplx( rZero, rZero ) |
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em(2) = dcmplx( rZero, rZero ) |
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em(3) = dcmplx( rOne , rZero ) |
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em(4) = dcmplx( rZero, rZero ) |
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else if ( nhel.eq.-2.or.nhel.eq.0 ) then |
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em(1) = dcmplx( rZero, rZero ) |
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em(2) = dcmplx( rZero, rZero ) |
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em(3) = dcmplx( rZero, rZero ) |
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em(4) = dcmplx( rOne , rZero ) |
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end if |
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do j = 1,4 |
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do i = 1,4 |
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tc(i,j) = ep(i)*em(j) |
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end do |
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end do |
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c
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ft(1)=tc(1,1) |
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ft(2)=tc(1,2) |
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ft(3)=tc(1,3) |
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ft(4)=tc(1,4) |
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ft(5)=tc(2,1) |
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ft(6)=tc(2,2) |
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ft(7)=tc(2,3) |
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ft(8)=tc(2,4) |
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ft(9)=tc(3,1) |
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ft(10)=tc(3,2) |
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ft(11)=tc(3,3) |
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ft(12)=tc(3,4) |
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ft(13)=tc(4,1) |
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ft(14)=tc(4,2) |
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ft(15)=tc(4,3) |
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ft(16)=tc(4,4) |
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ft(17)=tc(5,1) |
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ft(18)=tc(6,1) |
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return |
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end |