Scattering amplitudes with massive fermions using BCFW recursion
نویسندگان
چکیده
We study the QCD scattering amplitudes for q̄q → gg and q̄q → ggg where q is a massive fermion. Using a particular choice of massive fermion spinor we are able to derive very compact expressions for the partial spin amplitudes for the 2 → 2 process. We then investigate the corresponding 2 → 3 amplitudes using the BCFW recursion technique. For the helicity conserving partial amplitudes we again derive very compact expressions, but were unable to treat the helicity-flip amplitudes recursively, except for the case where all the gluon helicities are the same. We therefore evaluate the remaining partial amplitudes using standard Feynman diagram techniques.
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