Eur. Phys. J. C (2006) 48: 159-168
https://doi.org/10.1140/epjc/s10052-006-0007-7

Theoretical Physics

Scattering amplitudes with massive fermions using BCFW recursion

Institute for Particle Physics Phenomenology, University of Durham, Durham, DH1 3LE, UK

^* e-mail: kemal.ozeren@durham.ac.uk

Received: 17 June 2006
Published online: 28 September 2006

Abstract

We study the QCD scattering amplitudes for and where q is a massive fermion. Using a particular choice of massive fermion spinor we derive 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 present new expressions, but we 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.