Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: HI in radio galaxies: prospects for upcoming wide-field surveys   We present results of an ongoing systematic study of the large-scale
properties of neutral hydrogen (HI) gas in nearby radio galaxies. Our main goal
is to investigate the importance of gas-rich galaxy mergers and interactions
among radio-loud AGN. From an HI study of a complete sample of classical
low-power radio galaxies we find that the host galaxies of extended Fanaroff &
Riley type-I radio sources are generally HI poor (< 10E8 M_sun) and show no
indications for gas-rich galaxy mergers or ongoing gas-rich interactions. In
contrast, the host galaxies of a significant fraction of low-power compact
radio sources contain enormous discs/rings of HI gas (with sizes up to 190 kpc
and masses up to 2 x 10E10 M_sun). This segregation in HI mass with radio
source size likely indicates that these compact radio sources are either
confined by large amounts of gas in the central region, or that their fueling
is inefficient and different from the fueling process of classical FR-I radio
sources. To a first order, the overall HI properties of our complete sample
(detection rate, mass and morphology) appear similar to those of radio-quiet
early-type galaxies. If confirmed by better statistics, this would imply that
low-power radio-AGN activity may be a short phase that occurs at some point
during the lifetime of many early-type galaxies. We discuss how upcoming HI
surveys (e.g. with ASKAP and Apertif) are essential for studying in a
statistical way the the connection between the presence and morphology of a
radio-loud AGN and the properties of the cold HI gas associated with its host
galaxy.

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The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
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The categories of this paper are: funct-an
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The categories of this paper are: dg-ga
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The categories of this paper are: eess
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The categories of this paper are: nlin
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The categories of this paper are: chem-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: hep-ex
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The categories of this paper are: solv-int
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The categories of this paper are: q-bio
0
The categories of this paper are: hep-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: nucl-th
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-th