Name: D.Y.Chen Date: 01/22/10-01:48:41 PM Z


Hi,

I have a problem in my calculations for a triangle diagram. One term in the amplitude is
   Amp=FV[q,\[Mu]].FV[q,\[Nu]].FV[q,\[Alpha]].FV[q,\[Beta]]*
       FAD[{p3+q,m1},{p4-q,m2},{q,mD}].FAD[{q,Lambda}]^2
All these four Lorentz index are contract with polarization tensor and polarization vector.
          _________ p3
         /|
 p0 m1 / |
_______/ | q
       \ |
     m2 \ |
         \|________ p4

I hope the above figure is clear for you. The initial particle is spin-2 state while the final states are two spin-1 particles. The part FAD[{q,Lambda}] is introduced by the form factors or some else.

I do not know how to deal with this term and hope someone can give me some useful suggestions!

Best Wishes!

D. Y. Chen