Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: RX J1624.9+7554: A new X-ray transient AGN   We report the discovery of a new X-ray transient AGN, RX J1624.9+7554. This
object appeared to be bright in the ROSAT All-Sky Survey, but had turned off in
two pointed observations about one and a half years later. The optical
identification spectrum shows a non-emission line spectrum of a spiral galaxy
at z=0.064. %We will discuss several hypotheses that can explain the peculiar
behaviour of %this object. We will discuss several hypotheses that can explain
the peculiar behaviour of this object.

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The categories of this paper are: nlin
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The categories of this paper are: acc-phys
1
The categories of this paper are: cs
30
The categories of this paper are: q-alg
22
The categories of this paper are: chao-dyn
3
The categories of this paper are: physics
33
The categories of this paper are: plasm-ph
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The categories of this paper are: eess
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The categories of this paper are: nucl-th
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The categories of this paper are: alg-geom
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The categories of this paper are: math-ph
35
The categories of this paper are: mtrl-th
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The categories of this paper are: atom-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: funct-an
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The categories of this paper are: hep-ex