Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dibaryons cannot be the dark matter   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.

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The categories of this paper are: math-ph
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The categories of this paper are: eess
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The categories of this paper are: acc-phys
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The categories of this paper are: gr-qc
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The categories of this paper are: adap-org
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The categories of this paper are: solv-int
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The categories of this paper are: mtrl-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: q-fin
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The categories of this paper are: cond-mat
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The categories of this paper are: funct-an
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The categories of this paper are: nlin
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The categories of this paper are: comp-gas
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The categories of this paper are: atom-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: nucl-ex