Dibaryons cannot be the dark matter

Journal Article · 19 March 2019 · Physical Review. D.

DOI: https://doi.org/10.1103/physrevd.99.063519 · OSTI ID:1501725

Kolb, Edward W. ^[1]; Turner, Michael S. ^[1]

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1. Univ. of Chicago, IL (United States)

The hypothetical SU(3) flavor-singlet dibaryon state S with strangeness –2 has been discussed as a dark-matter candidate capable of explaining the curious 5-to-1 ratio of the mass density of dark matter to that of baryons. We study the early-universe production of dibaryons and find that irrespective of the hadron abundances produced by the QCD quark/hadron transition, rapid particle reactions thermalized the S abundance, and it tracked equilibrium until it “froze out” at a tiny value. For the plausible range of dibaryon masses (1860–1890 MeV) and generous assumptions about its interaction cross sections, S’s account for at most 10^–11 of the baryon number and, thus, cannot be the dark matter. Although it is not the dark matter, if the S exists, it might be an interesting relic.

• Research Organization: Univ. of Chicago, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC); USDOE
• Grant/Contract Number: SC0009924; FG02-13ER41958
• OSTI ID: 1501725
• Alternate ID(s): OSTI ID: 1611253
• Journal Information: Physical Review. D., Vol. 99, Issue 6; ISSN 2470-0010
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English