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Inelastically decoupling dark matter

Ronny Frumkin1,2, Yonit Hochberg1,3, Eric Kuflik1,3, and Binyamin Vilk1

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Phys. Rev. D 113, 015004 – Published 6 January, 2026

DOI: https://doi.org/10.1103/52fd-b266

Abstract

We present a new dark matter candidate, the inelastically decoupling relic (iELDER), which is a cold thermal relic whose abundance is determined by the freeze out of its inelastic scattering off of bath particles in the presence of 3→2 self-annihilations. The dark matter is predicted to be light, in the O(MeV−GeV) range, with significant self-annihilations and very weak inelastic couplings to ordinary matter. We demonstrate iELDER dark matter using a Z3-symmetric toy model as well as quantum chromodynamics (QCD)-like pion theories—the latter showing promising prospects for detection and providing a new benchmark for future searches.

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Phys. Rev. D 113, 015004– Published 6 January, 2026
  • Received 7 September 2025
  • Accepted 18 December 2025
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