Automated one-loop computations in the SMEFT

TL;DR

This paper introduces SMEFT@NLO, an automated framework for one-loop calculations in the Standard Model Effective Field Theory, enabling precise predictions for collider phenomenology involving top quarks, electroweak, and Higgs processes.

Contribution

The paper presents the first comprehensive automation of one-loop computations in SMEFT at dimension six, covering all operator types with full differential prediction capabilities.

Findings

Demonstrates the implementation with novel NLO computations for top-quark and Higgs processes.

Enables fully differential predictions matched to parton showers.

Facilitates precise phenomenological studies at the LHC and future colliders.

Abstract

We present the automation of one-loop computations in the standard-model effective field theory at dimension six. Our general implementation, dubbed SMEFT@NLO, covers all types of operators: bosonic, two- and four-fermion ones. Included ultraviolet and rational counterterms presently allow for fully differential predictions, possibly matched to parton shower, up to the one-loop level in the strong coupling or in four-quark operator coefficients. Exact flavor symmetries are imposed among light quark generations and an initial focus is set on top-quark interactions in the fermionic sector. We illustrate the potential of this implementation with novel loop-induced and next-to-leading-order computations relevant for top-quark, electroweak, and Higgs-boson phenomenology at the LHC and future colliders.