Mapping the SMEFT to discoverable models

TL;DR

This paper develops an automated diagrammatic method to systematically map SMEFT operators back to potential UV models, focusing on models that contribute to four-fermion operators at one-loop, which could be detectable at the LHC.

Contribution

It introduces a new automated diagrammatic technique for systematically constructing UV models from SMEFT operators, especially those with loop-level contributions to four-fermion interactions.

Findings

Generated UV models with no tree-level four-fermion contributions.

Identified models with light particles detectable at the LHC.

Explored the interplay between SMEFT analyses and direct collider searches.

Abstract

The matching of specific new physics scenarios onto the SMEFT framework is a well-understood procedure. The inverse problem, the matching of the SMEFT to UV scenarios, is more difficult and requires the development of new methods to perform a systematic exploration of models. In this paper we use a diagrammatic technique to construct in an automated way a complete set of possible UV models (given certain, well specified assumptions) that can produce specific groups of SMEFT operators, and illustrate its use by generating models with no tree-level contributions to four-fermion (4F) operators. Those scenarios, which only contribute to 4F at one-loop order, can contain relatively light particles that could be discovered at the LHC in direct searches. For this class of models, we find an interesting interplay between indirect SMEFT and direct searches. We discuss some examples on how this interplay would look like when combining low-energy observables with the SMEFT Higgs-fermion analyses and searches for resonance at the LHC.