Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Hidden Blazars and Emission Line Variability of High Redshift Quasars   We have carried out a survey to search for hidden blazars in a sample of
$z{\sim}2$ radio-loud quasars. The idea is based on our prediction that we
should be able to see large CIV line variability not associated with observed
continuum variations or most other emission lines in every radio-loud quasar.
Here we report the initial results including the discovery of large CIV line
variations in two quasars.

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The categories of this paper are: dg-ga
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The categories of this paper are: chao-dyn
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The categories of this paper are: math-ph
1
The categories of this paper are: cs
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The categories of this paper are: ao-sci
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The categories of this paper are: q-fin
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The categories of this paper are: hep-ph
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The categories of this paper are: math
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The categories of this paper are: patt-sol
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The categories of this paper are: q-alg
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The categories of this paper are: alg-geom
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The categories of this paper are: hep-th
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The categories of this paper are: adap-org
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The categories of this paper are: bayes-an
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The categories of this paper are: atom-ph
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The categories of this paper are: acc-phys