Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Arecibo Galaxy Environment Survey: Precursor Observations of the NGC
  628 group   The Arecibo Galaxy Environment Survey (AGES) is one of several HI surveys
utilising the new Arecibo L-band Feed Array (ALFA) fitted to the 305m radio
telescope at Arecibo. The survey is specifically designed to investigate
various galactic environments to higher sensitivity, higher velocity resolution
and higher spatial resolution than previous fully sampled, 21 cm multibeam
surveys. The emphasis is on making detailed observations of nearby objects
although the large system bandwidth (100 MHz) will allow us to quantify the HI
properties over a large instantaneous velocity range.
  In this paper we describe the survey and its goals and present the results
from the precursor observations of a 5 degree x 1 degree region containing the
nearby (~10 Mpc) NGC 628 group. We have detected all the group galaxies in the
region including the low mass (M{HI}~10^7Mo) dwarf, dw0137+1541 (Briggs, 1986).
The fluxes and velocities for these galaxies compare well with previously
published data. There is no intra-group neutral gas detected down to a limiting
column density of 2x10^{18}cm^{-2}. In addition to the group galaxies we have
detected 22 galaxies beyond the NGC 628 group, 9 of which are previously
uncatalogued.(Abridged)

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The categories of this paper are: hep-lat
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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: plasm-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: comp-gas
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The categories of this paper are: supr-con
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The categories of this paper are: funct-an
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The categories of this paper are: nucl-th
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The categories of this paper are: hep-ph
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The categories of this paper are: q-fin
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The categories of this paper are: hep-th
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The categories of this paper are: nucl-ex
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The categories of this paper are: chao-dyn
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The categories of this paper are: dg-ga
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The categories of this paper are: q-alg