Twistor-inspired construction of massive quark amplitudes

Understand

The analog of the Cachazo-Svrvcek-Witten rules for scattering amplitudes with massive quarks is derived following an approach previously employed for amplitudes with massive scalars.

• A prescription for the external wave-functions is given that leads to a one-to one relation between fields in the action and spin-states of massive quarks.
• Several examples for the application of the rules are given and the structure of some all-multiplicity amplitudes with a pair of massive quarks is discussed.
• The rules make supersymmetric relations to amplitudes with massive scalars manifest at the level of the action.