Ordering multiple soft gluon emissions

Understand

We present an expression for the QCD amplitude for a general hard scattering process with any number of soft gluon emissions, to one-loop accuracy.

• The amplitude is written in two different but equivalent ways: as a product of operators ordered in dipole transverse momentum and as a product of loop-expanded currents.
• We hope that these results will help in the development of an all-orders algorithm for multiple emissions that includes the full colour structure and both the real and imaginary contributions to the amplitude.