The T-Wilson Line

TL;DR

This paper introduces the T-Wilson line, a new gauge link component in soft-collinear effective theory, essential for gauge-invariant definitions of non-perturbative matrix elements relevant for high-energy collider processes.

Contribution

It identifies and formulates the T-Wilson line, a novel gauge link constructed from the transverse gluon field, addressing a missing ingredient in the current effective theory.

Findings

The T-Wilson line is neither soft nor collinear.

Inclusion of the T-Wilson line ensures gauge invariance of certain matrix elements.

The feature is crucial for analyzing semi-inclusive processes at the LHC.

Abstract

We argue that soft-collinear effective theory, as is currently formulated, lacks an ingredient which is essential for obtaining a gauge invariant definitions of certain non-perturbative matrix elements relevant for semi-inclusive high-energy processes. Those processes and the companion cross-sections are to be analyzed and measured at the Large Hadron Collider. The missing feature is a gauge link constructed only from the transverse component of the gluon field denoted by the "$T$-Wilson line"'. It is neither soft nor collinear. As such it is a new feature of the theory.