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arXiv · hep-ph/0703021

On-shell recursion relations for all Born QCD amplitudes

Christian Schwinn·Stefan Weinzierl
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Abstract

We consider on-shell recursion relations for all Born QCD amplitudes. This includes amplitudes with several pairs of quarks and massive quarks. We give a detailed description on how to shift the external particles in spinor space and clarify the allowed helicities of the shifted legs. We proof that the corresponding meromorphic functions vanish at z --> infinity. As an application we obtain compact expressions for helicity amplitudes including a pair of massive quarks, one negative helicity gluon and an arbitrary number of positive helicity gluons.

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Christian Schwinn, Stefan Weinzierl. 2007-04-16. On-shell recursion relations for all Born QCD amplitudes. https://doi.org/10.1088/1126-6708%2F2007%2F04%2F072

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