Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the masses of black-holes in radio-loud quasars   The central black-hole masses of a sample of radio-loud quasars are estimated
by using the data of $H_{\beta}$ line-width and the optical continuum
luminosity. The vast majority of the quasars in this sample have black-hole
masses larger than $10^{8} M_{\odot}$, while a few quasars may contain
relatively smaller black-holes. We found a significant anti-correlation between
the radio-loudness and the central black-hole mass. It might imply that the jet
formation is governed by the black-hole mass.

35
The categories of this paper are: mtrl-th
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The categories of this paper are: cmp-lg
4
The categories of this paper are: cond-mat
8
The categories of this paper are: hep-ex
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The categories of this paper are: hep-ph
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The categories of this paper are: eess
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The categories of this paper are: stat
5
The categories of this paper are: gr-qc
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The categories of this paper are: dg-ga
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The categories of this paper are: math-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: quant-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: nucl-th
15
The categories of this paper are: nucl-ex
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The categories of this paper are: supr-con