Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Discovery of Radio-loud Broad Absorption Line Quasars Using Ultraviolet
  Excess and Deep Radio Selection   We report the discovery of five broad-absorption-line (BAL) QSOs in a
complete sample of 111 ultraviolet excess (UVX) QSO candidates also detected in
the NRAO VLA Sky Survey. All five BAL QSOs, which include two high-ionization
BAL QSOs and three low-ionization BAL QSOs, are formally radio-loud. Of QSOs
with z > 0.4, 3+/-2% show low-ionization BALs, and of QSOs with z > 1.5, all
radio-loud, 9+/-5% show BALs; these frequencies are consistent with those of
optical surveys. While the first reported radio-loud BAL QSO, FIRST
J155633.8+351758, is likely to be heavily dust reddened and thus less
radio-loud than indicated by its observed radio-to-optical luminosity, these
QSOs are UVX selected and probably free of significant dust along the line of
sight. We point out unusual features in two of the BAL QSOs and discuss the
significance finding these heretofore rare objects.

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The categories of this paper are: math-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: stat
29
The categories of this paper are: funct-an
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The categories of this paper are: patt-sol
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The categories of this paper are: comp-gas
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The categories of this paper are: nucl-th
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The categories of this paper are: cs
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The categories of this paper are: q-fin
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The categories of this paper are: quant-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: math
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The categories of this paper are: gr-qc
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The categories of this paper are: q-alg
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The categories of this paper are: cond-mat
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The categories of this paper are: bayes-an