Integrating out resonances in strongly-coupled electroweak scenarios

TL;DR

This paper explores how integrating out heavy resonances in a strongly-coupled electroweak symmetry breaking scenario refines the low-energy effective theory couplings, linking them to high-energy resonance parameters.

Contribution

It provides a systematic method to relate low-energy couplings to heavy resonance parameters using a non-linear electroweak symmetry breaking framework.

Findings

Low-energy couplings are expressed in terms of resonance parameters.

Short-distance constraints reduce the number of free resonance couplings.

The approach improves the precision of effective theory predictions.

Abstract

Accepting that there is a mass gap above the electroweak scale, the Electroweak Effective Theory (EWET) is an appropriate tool to describe this situation. Since the EWET couplings contain information on the unknown high-energy dynamics, we consider a generic strongly-coupled scenario of electroweak symmetry breaking, where the known particle fields are coupled to heavier states. Then, and by integrating out these heavy fields, we study the tracks of the lightest resonances into the couplings. The determination of the low-energy couplings (LECs) in terms of resonance parameters can be made more precise by considering a proper short-distance behaviour on the Lagrangian with heavy states, since the number of resonance couplings is then reduced. Notice that we adopt a generic non-linear realization of the electroweak symmetry breaking with a singlet Higgs.