# NLO electroweak corrections in general scalar singlet models

## TL;DR

This paper develops a general method to compute one-loop electroweak corrections in scalar singlet extended models of the Standard Model, assessing their impact on Higgs processes and dark matter scenarios.

## Contribution

It introduces a universal framework for calculating one-loop corrections in BSM models with multiple scalar singlets and applies it to specific models to evaluate their phenomenological significance.

## Key findings

- Corrections are at most a few percent within current parameter space.
- Non-zero corrections can persist in dark matter scenarios with SM-like Higgs couplings.
- The method enables precise predictions for Higgs processes in extended scalar models.

## Abstract

If no new physics signals are found, in the coming years, at the Large Hadron Collider Run-2, an increase in precision of the Higgs couplings measurements will shift the dicussion to the effects of higher order corrections. In Beyond the Standard Model (BSM) theories this may become the only tool to probe new physics. Extensions of the Standard Model (SM) with several scalar singlets may address several of its problems, namely to explain dark matter, the matter-antimatter asymmetry, or to improve the stability of the SM up to the Planck scale. In this work we propose a general framework to calculate one loop-corrections in BSM models with an arbitrary number of scalar singlets. We then apply our method to a real and to a complex scalar singlet models. We assess the importance of the one-loop radiative corrections first by computing them for a tree level mixing sum constraint, and then for the main Higgs production process $gg \to H$. We conclude that, for the currently allowed parameter space of these models, the corrections can be at most a few percent. Notably, a non-zero correction can survive when dark matter is present, in the SM-like limit of the Higgs couplings to other SM particles.