Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Exotic Spin-Dependent Interaction Searches at Indiana University   The axion is a hypothesized particle appearing in various theories beyond the
Standard Model. It is a light spin-0 boson initially postulated to solve the
strong CP problem and is also a strong candidate for dark matter. If the axion
or an axion-like particle exists, it would mediate a P-odd and T-odd
spin-dependent interaction. We describe two experiments under development at
Indiana University-Bloomington to search for such an interaction.

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The categories of this paper are: atom-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: adap-org
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The categories of this paper are: nucl-th
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The categories of this paper are: comp-gas
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The categories of this paper are: patt-sol
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The categories of this paper are: cond-mat
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The categories of this paper are: hep-lat
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The categories of this paper are: physics
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The categories of this paper are: eess
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The categories of this paper are: alg-geom
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The categories of this paper are: econ
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The categories of this paper are: nlin
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The categories of this paper are: ao-sci
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The categories of this paper are: gr-qc
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The categories of this paper are: q-fin