The Cosmology of Composite Inelastic Dark Matter

93 citations (86 excluding self-citations). The cosmological companion to “Composite Inelastic Dark Matter,” working out the early-universe production and hadronization of dark mesons and baryons.

The Problem

The Composite Inelastic Dark Matter paper proposed that dark matter is a meson of a hidden QCD-like sector, with hyperfine splittings explaining the DAMA signal. But a hidden QCD produces more than mesons: it produces baryons, antibaryons, and potentially a dark baryon asymmetry. The early-universe cosmology — the synthesis of constituent dark quarks into dark hadrons as the hidden sector cools through its confinement transition — determines the final abundances of each species and whether the model is viable.

The Key Results

The paper traces the cosmological history of the dark sector through confinement, finding that the relative masses of the light and heavy constituent quarks produce qualitatively different outcomes: a light-quark-dominated sector produces mostly mesons with a small baryon fraction, while a heavy-quark-dominated sector can produce significant dark baryon abundances. The dark hadron synthesis is analogous to big bang nucleosynthesis in the visible sector but with different dynamics due to the different gauge group and mass hierarchy.

Recollections

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• DOI
• arXiv:1003.4729
• INSPIRE