Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: XMM Observations of an IXO in NGC 2276   We present the results from a ~53 ksec XMM observation of NGC 2276. This
galaxy has an unusual optical morphology with the disk of this spiral appearing
to be truncated along the western edge. This XMM observation shows that the
X-ray source at the western edge is a bright Intermediate X-ray Object (IXO).
Its spectrum is well fit by a multi-color disk blackbody model used to fit
optically thick standard accretion disks around black holes. The luminosity
derived for this IXO is 1.1x10^41 erg/s in the 0.5 - 10 keV band making it one
of the most luminous discovered to date. The large source luminosity implies a
large mass black hole if the source is radiating at the Eddington rate. On the
other hand, the inner disk temperature determined here is too high for such a
massive object given the standard accretion disk model. In addition to the IXO
we find that the nuclear source in this galaxy has dimmed by at least a factor
of several thousand in the eight years since the ROSAT HRI observations.

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The categories of this paper are: alg-geom
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-lat
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The categories of this paper are: q-alg
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The categories of this paper are: chao-dyn
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The categories of this paper are: mtrl-th
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The categories of this paper are: bayes-an
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The categories of this paper are: quant-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: math-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: comp-gas
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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: chem-ph
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The categories of this paper are: cond-mat