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arXiv · 2611.00930

From Kination to Detection: Scotogenic Scalar Dark Matter

Eung Jin Chun·Ranjeet Kumar·Sanjoy Mandal·Abhishek Roy
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Abstract

We investigate scalar dark matter in the scotogenic model during an early kination-dominated epoch. The enhanced expansion rate causes earlier freeze-out and increases the relic abundance, opening viable dark matter masses from approximately $200~\mathrm{GeV}$ to $1~\mathrm{TeV}$ while reducing the need for co-annihilation with a nearly degenerate singlet fermion. Current indirect searches strongly constrain the $(100-200)~\mathrm{GeV}$ region, whereas much of the surviving parameter space can be probed by CTA and next-generation direct detection experiments. The viable spectra also lead to complementary collider signatures, including missing transverse energy, displaced leptons, and disappearing charged tracks, providing promising tests at the HL-LHC and future lepton colliders.

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Eung Jin Chun, Ranjeet Kumar, Sanjoy Mandal, Abhishek Roy. 2026-10-31. From Kination to Detection: Scotogenic Scalar Dark Matter. https://arxiv.org/abs/2611.00930

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