Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Overview of the Cosmic Axion Spin Precession Experiment (CASPEr)   An overview of our experimental program to search for axion and
axion-like-particle (ALP) dark matter using nuclear magnetic resonance (NMR)
techniques is presented. An oscillating axion field can exert a time-varying
torque on nuclear spins either directly or via generation of an oscillating
nuclear electric dipole moment (EDM). Magnetic resonance techniques can be used
to detect such an effect. The first-stage experiments explore many decades of
ALP parameter space beyond the current astrophysical and laboratory bounds. It
is anticipated that future versions of the experiments will be sensitive to the
axions associated with quantum chromodynamics (QCD) having masses $\lesssim
10^{-9}~{\rm eV}/c^2$.

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The categories of this paper are: mtrl-th
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The categories of this paper are: dg-ga
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The categories of this paper are: atom-ph
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The categories of this paper are: econ
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The categories of this paper are: cond-mat
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The categories of this paper are: adap-org
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The categories of this paper are: q-fin
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The categories of this paper are: ao-sci
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The categories of this paper are: stat
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The categories of this paper are: q-alg
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The categories of this paper are: cmp-lg
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The categories of this paper are: eess
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The categories of this paper are: math
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The categories of this paper are: gr-qc
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The categories of this paper are: nucl-th
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The categories of this paper are: acc-phys