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arXiv · hep-ph/0603071

Scattering amplitudes with massive fermions using BCFW recursion

K. J. Ozeren·W. J. Stirling
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Abstract

We study the QCD scattering amplitudes for \bar{q}q \to gg and \bar{q}q \to 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 \to 2 process. We then investigate the corresponding 2 \to 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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K. J. Ozeren, W. J. Stirling. 2006-03-09. Scattering amplitudes with massive fermions using BCFW recursion. https://doi.org/10.1140/epjc%2Fs10052-006-0007-7

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