Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Position-velocity diagrams of ionized gas in the inner regions of disk
  galaxies   We use long-slit spectroscopy along the major axis of a sample of 23 nearby
disk galaxies to study the kinematic properties of the ionized-gas component in
their inner regions. For each galaxy, we derive the position-velocity diagram
of the ionized gas from its emission lines. We discuss the variety of shapes
observed in such position-velocity diagrams by comparing the gas velocity
gradient, velocity dispersion and integrated flux measured in the inner (r
+/-1'') and outer regions (r +/-4''). This kind of analysis allows the
identification of galaxies which are good candidates to host a circumnuclear
Keplerian gaseous disk rotating around a central mass concentration, and to
follow up with Hubble Space Telescope observations.

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The categories of this paper are: alg-geom
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The categories of this paper are: math
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The categories of this paper are: q-fin
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The categories of this paper are: q-alg
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The categories of this paper are: hep-lat
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The categories of this paper are: math-ph
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The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
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The categories of this paper are: nucl-ex
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The categories of this paper are: cmp-lg
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The categories of this paper are: atom-ph
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The categories of this paper are: solv-int
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The categories of this paper are: hep-th
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The categories of this paper are: hep-ex
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The categories of this paper are: econ