  Physics beyond the Fermi scale could show up through deviations of the gauge
couplings predicted by the electroweak Yang-Mills sector. This possibility is
explored in the context of the International Linear Collider (ILC) through the
helicity amplitudes for the gamma e -> W nu_e reaction to which contributes the
trilinear WWgamma coupling. The new physics effects on this vertex are
parametrized in a model-independent fashion through an effective electroweak
Yang-Mills sector, which is constructed by considering two essentially
different sources of new physics. In one scenario, Lorentz violation will be
considered exclusively as the source of new physics effects. This type of new
physics is considered in an extension of the Standard Model that is known as
the Standard Model Extension (SME), which is an effective field theory that
contemplates CPT and Lorentz violation in a model-independent fashion. Any
source of new physics that respects the Lorentz symmetry, will be considered
within the general context of the well known Conventional Effective Standard
Model (CESM) extension. Both the SME and the CESM descriptions include gauge
invariant operators of dimension higher than four, which, in general, transform
as Lorentz tensors of rank higher than zero. Whereas in the former theory
observer Lorentz invariants are constructed by contracting these operators with
constant Lorentz tensors, in the latter the corresponding Lorentz invariant
interactions are obtained contracting such operators with products of the
metric tensor. We focus our study on the possibility of experimentally
distinguish both types of new physics effects on the WWgamma vertex. It is
found that for a new physics scale of the same order of magnitude and under
determined circumstances, both types of new physics effects will be clearly
distinguished.
