Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the Distance to the Bright Nonthermal Radio Sources in the Direction
  of an Extraordinarily Massive Cluster of Red Giants   An extraordinarily massive cluster of red supergiants has been recently
reported in the direction of the galactic coordinates $l = 25\rlap.^\circ3$; $b
= -0\rlap.^\circ2$. This cluster is associated with an X-ray source, a very
high-energy $\gamma$-ray source, and three bright non-thermal radio sources.
The \sl a priori \rm probability of these associations being only line-of-sight
coincidences is very small. However, we have analyzed VLA archive data taken
toward these three radio sources and find from their HI absorption spectra that
they are extragalactic and thus not directly associated with the galactic
cluster.

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The categories of this paper are: q-fin
11
The categories of this paper are: hep-lat
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The categories of this paper are: bayes-an
3
The categories of this paper are: physics
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
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The categories of this paper are: patt-sol
14
The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
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The categories of this paper are: adap-org
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The categories of this paper are: q-alg
20
The categories of this paper are: acc-phys
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The categories of this paper are: ao-sci
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The categories of this paper are: comp-gas
2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th