Relic density of dark matter in the inert doublet model beyond leading order for the low mass region: 3. Annihilation in 3-body final state

TL;DR

This paper calculates the first one-loop electroweak corrections for dark matter annihilation into three-body final states in the inert doublet model, revealing significant effects on relic density predictions beyond tree-level estimates.

Contribution

It provides the first detailed one-loop electroweak correction analysis for 2-to-3 dark matter annihilation processes in the low mass region of the inert doublet model.

Findings

One-loop corrections significantly affect relic density calculations.

Rescattering effects introduce dependence on dark sector parameters.

Theoretical uncertainties are larger than commonly assumed.

Abstract

We perform the first one-loop electroweak corrections for $2 \to 3$ processes for dark matter annihilation. These are the dominant processes that enter the computation of the relic density for the low mass region of the inert doublet model (IDM) when annihilations to two on-shell vector bosons are closed. The impact of the one-loop corrections are important as they involve, through rescattering effects, not only a dependence on the parameter controlling the dark sector, not present if a calculation at tree-level is conducted, but also on the renormalisation scale. These combined effects should be taken into account in analyses based on tree-level cross-sections of the relic density calculations, as a theoretical uncertainty which we find to be much larger than the cursory $\pm 10\%$ uncertainty that is routinely assumed, independently of the model parameters.