Top quark loop corrections to $W^+W^-$ scattering in EChL

TL;DR

This paper evaluates fermion-loop corrections to high energy W+W- scattering within the Higgs Effective Field Theory, revealing that these corrections can be significant in certain parameter regions, challenging common assumptions.

Contribution

It demonstrates that fermion-loop corrections can be as important as boson-loop corrections in specific parameter spaces of the HEFT, which was previously underestimated.

Findings

Fermion-loops can be relevant in certain HEFT parameter regions.

Common assumption of negligible fermion-loops is not always valid.

Deviations from Standard Model couplings affect loop correction significance.

Abstract

We calculate fermion-loop corrections to high energy $W^+W^-$ scattering in the context of a Strongly Interacting Electroweak Symmetry Breaking Sector (EWSBS) using Higgs Effective Field Theory(HEFT). We test the assumption that these corrections are negligible when compared to the boson-loop ones, as it is commonly taken for granted in the literature. While this is correct inmost cases, we find that, for some particular regions of the parameter space, fermion-loops can be important: deviations in the couplings of the HEFT from their Standard Model values may lead to fermion-loop corrections as relevant as the boson-loop ones.