2010/09/30 by Ahmad Idilbi, Ignazio Scimemi · 69 citations
Physics and Astronomy · #Black Holes and Theoretical Physics #Covariant transformation #Effective field theory #Gauge theory #Gluon #Mathematical physics #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #Quark #hep-ph
paper · pdf · doi:10.1016/j.physletb.2010.11.060
published in Physics Letters B 695(5), 463-468 (Elsevier BV) · Version to appear in Phys. Lett. B. The discussion of the zero-bin subtraction is modified. Some typos corrected
openalex publication_date 2010/12/01 · arxiv created 2010/12/21 · arxiv updated 2011/01/04 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Gauge invariance in soft-collinear effective theory (SCET) is discussed in regular (covariant) and singular (light-cone) gauges. It is argued that SCET, as it stands, is not capable to define in a gauge invariant way certain non-perturbative matrix elements that are an integral part of many factorization theorems. Those matrix elements involve two quark or gluon fields separated not only in light-cone direction but also in the transverse one. This observation limits the range of applicability of SCET. To remedy this we argue that one needs to introduce a new Wilson line as part of SCET formalism, that we call T. This Wilson line depends only on the transverse component of the gluon field. As such it is a new feature to the SCET formalism and it guarantees gauge invariance of the non-perturbative matrix elements in both classes of gauges.