Speaker
Description
The Standard Model and Higgs Effective Field Theories (SMEFT and HEFT) are well-established theoretical frameworks for the parameterization of potential new physics signals from nearly decoupled BSM sectors. The two EFTs differ in the scalar field content and - most notably - in the power counting, i.e. the way they organize BSM effects into a series expansion. While in SMEFT the power counting simply expands in inverse powers of the EFT cutoff $\Lambda$, HEFT presents a more confusing power counting due to the simultaneous presence of linear and non-linear field representations.
This talk revisits general power counting rationales in EFTs with a focus on phenomenology, and discusses an example application to double Higgs production in gluon fusion, which is one of the main test benches for HEFT-SMEFT comparisons at the LHC.