Axino Cold Dark Matter Revisited

TL;DR

This paper reevaluates axino as a dark matter candidate, focusing on thermal and non-thermal production mechanisms, refining calculations, and clarifying model distinctions in light of recent developments.

Contribution

It provides a detailed review and refinement of axino production calculations, clarifies the relation between axino and axion across different models, and incorporates recent theoretical advances.

Findings

Refined computation of QCD axino production avoiding unphysical results

Clarified the relation between axino and axion in various models

Included additional production channels via SU(2), U(1), and Yukawa interactions

Abstract

Axino arises in supersymmetric versions of axion models and is a natural candidate for cold or warm dark matter. Here we revisit axino dark matter produced thermally and non-thermally in light of recent developments. First we discuss the definition of axino relative to low energy axion one for several KSVZ and DFSZ models of the axion. Then we review and refine the computation of the dominant QCD production in order to avoid unphysical cross-sections and, depending on the model, to include production via SU(2) and U(1) interactions and Yukawa couplings.