The Two Scales of New Physics in Higgs Couplings

TL;DR

This paper explores how deviations in Higgs couplings reveal two different energy scales of new physics, providing bounds on the scale of new bosons and implications for collider experiments and naturalness.

Contribution

It introduces a model-independent method to bound the scale of new bosons from Higgs coupling deviations, extending beyond effective field theory limitations.

Findings

Any observed deviation implies new bosons within experimental reach.

Upper bounds on new boson scales are derived for Higgs to WW and ZZ couplings.

Implications for naturalness and future collider searches are discussed.

Abstract

Higgs coupling deviations from Standard Model predictions contain information about two scales of Nature: that of new physics responsible for the deviation, and the scale where new bosons must appear. The two can coincide, but they do not have to. The scale of new bosons can be calculated by going beyond an effective field theory description of the coupling deviation. We compute model-independent upper bounds on the scale of new bosons for deviations in Higgs to $WW$ and $ZZ$ couplings, finding that any measured deviation at present or future colliders requires the existence of new bosons within experimental reach. This has potentially interesting implications for naturalness.