Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On Black Hole Masses and Radio Loudness in AGN   The distribution of radio to optical fluxes in AGN is bimodal. The physical
origin for this bimodality is not understood. In this Letter I describe
observational evidence, based on the Boroson & Green PG quasar sample, that the
radio loudness bimodality is strongly related to the black hole mass (M_BH).
Nearly all PG quasars with M_BH>10^9M_sun are radio loud, while quasars with
M_BH<3x10^8M_sun are practically all radio quiet. This result is consistent
with the dependence of quasar host galaxy morphology on radio loudness. There
is no simple physical explanation for this result, but it may provide a clue on
how jets are formed near massive black holes. The radio loudness--black hole
mass relationship suggests that the properties of various types of AGN may be
largely set by three basic parameters, M_BH, L/L_Eddington, and inclination
angle.

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The categories of this paper are: nucl-ex
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The categories of this paper are: ao-sci
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The categories of this paper are: mtrl-th
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The categories of this paper are: cond-mat
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The categories of this paper are: supr-con
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The categories of this paper are: quant-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: comp-gas
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The categories of this paper are: cmp-lg
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The categories of this paper are: chem-ph
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The categories of this paper are: q-alg
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The categories of this paper are: q-fin
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The categories of this paper are: dg-ga
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The categories of this paper are: bayes-an
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The categories of this paper are: stat
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The categories of this paper are: math-ph