On different ways to quantize Soft-Collinear Effective Theory

Abstract

Collinear fields in soft collinear effective theory (SCET) can be made invariant under collinear gauge transformations by multiplying them with collinear Wilson lines. We discuss how we can quantize SCET directly in terms of these gauge invariant fields, allowing to directly calculate S matrix elements using the gauge invariant collinear fields. We also show how for each collinear direction SCET can be written in terms of fields whose interactions are given by the usual QCD Lagrangian, and how external operators coupling these different directions can be constructed.

Figures (2)

• Figure 1: A subset of Feynman rules for the three different formulations of SCET. The (...) denote terms which do not contribute to the tadpole diagram of Fig. \ref{['fig1']}b) in Feynman gauge.
• Figure 2: Diagrams contributing to the gauge invariant jet function at one loop.