Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Intrinsic Absorption in Radio-Selected QSOs   Moderate resolution spectra have been recorded for a sample of radio-selected
QSOs (z=2.5) discovered in the ``Faint Images of the Radio Sky at Twenty
centimeters'' (FIRST) VLA survey. This work is motivated by the study of a
heterogeneous set of QSO absorption line spectra that showed that as many as
36% of the absorbers normally thought to be intergalactic are correlated with
physical properties of the background QSO, including the radio source spectral
index. Spectra were taken for 24 newly discovered quasars in order to test this
finding on a more homogeneous data set. The spectra have been searched for the
most frequently observed absorption lines. The absorption line properties are
compared to the radio properties of the quasars. The primary results are
summarized as follows: 1) an excess of CIV absorbers in flat-spectrum quasars
as compared to steep-spectrum quasars is confirmed (based on a total sample of
165 systems), 2) a small excess of high-velocity CIV absorbers is seen in
radio-quiet QSOs as compared to radio-loud quasars, and 3) the Sloan Digital
Sky Survey QSO spectra will allow for the detection of a high-velocity, narrow,
intrinsic population of absorbers that is as small as 7% of the CIV absorber
population in QSOs at z=2.5.

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The categories of this paper are: hep-th
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The categories of this paper are: acc-phys
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The categories of this paper are: stat
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The categories of this paper are: mtrl-th
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The categories of this paper are: q-bio
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The categories of this paper are: chem-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: math-ph
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The categories of this paper are: physics
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The categories of this paper are: hep-lat
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The categories of this paper are: math
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The categories of this paper are: funct-an
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The categories of this paper are: solv-int
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The categories of this paper are: cond-mat
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The categories of this paper are: plasm-ph
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The categories of this paper are: gr-qc