Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Decoupled Nuclei and Nuclear Polar Rings in Regular Spiral Galaxies. NGC
  2841   The Sb galaxy NGC 2841 was observed at the 6 m telescope of SAO RAS with the
Multi-Pupil Field Spectrograph and at the 1 m telescope of SAO RAS with the
long-slit spectrograph. An unresolved nucleus of NGC 2841 is shown to be
chemically decoupled both in magnesium and in iron with abundance break
estimates of 0.36 dex for Mg and 0.6 dex for Fe; an abundance gradient in the
bulge is seen only in the magnesium index and is typical for early-type disk
galaxies. The rotation axis of the nuclear ionized gas in NGC 2841 is
orthogonal to that of the central stellar population; an existence of a bulge
stellar component with decoupled rotation momentum in the radius range 5" -12"
is suspected. A possible scenario for the origin of the unusual central
structure in NGC 2841 is proposed.

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The categories of this paper are: q-fin
5
The categories of this paper are: gr-qc
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The categories of this paper are: solv-int
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The categories of this paper are: q-alg
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The categories of this paper are: alg-geom
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The categories of this paper are: chao-dyn
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The categories of this paper are: ao-sci
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The categories of this paper are: bayes-an
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The categories of this paper are: quant-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: chem-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: nucl-ex
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The categories of this paper are: acc-phys
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The categories of this paper are: funct-an
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The categories of this paper are: stat