Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Further Evidence that Some Quasars Originate in Nearby Galaxies: NGC3628   NGC3628 is a well-studied starburst/low level AGN galaxy in the Leo Triplet
noted for its extensive outgassed plumes of neutral hydrogen. Catalogued QSOs
are shown to be concentrated around NGC3628 and aligned with HI plumes. The
chance that the three nearest quasars would accidentally fall as close as they
do is <= 0.01. The nearest quasar has a redshift of z = 2.15 and is at the tip
of an X-ray filament emerging along the minor axis plume. Location at this
point has an accidental probability of ~ 2x10^{-4}. In addition an unusual
optical filament also points directly at this quasar.

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The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
37
The categories of this paper are: supr-con
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The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
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The categories of this paper are: solv-int
9
The categories of this paper are: nlin
2
The categories of this paper are: math
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The categories of this paper are: cmp-lg
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The categories of this paper are: bayes-an
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The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
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The categories of this paper are: adap-org
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The categories of this paper are: plasm-ph
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The categories of this paper are: chem-ph