Spin-Dependent Antenna Splitting Functions

Understand

We consider parton showers based on radiation from QCD dipoles or `antennae'.

• These showers are built from 2->3 parton splitting processes.
• The question then arises of what functions replace the Altarelli-Parisi splitting functions in this approach.
• We give a detailed answer to this question, applicable to antenna showers in which partons carry definite helicity, and to both initial- and final-state emissions.