Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The peculiar Galactic center neutron star X-ray binary XMM
  J174457-2850.3   The recent discovery of a milli-second radio pulsar experiencing an accretion
outburst similar to those seen in low mass X-ray binaries, has opened up a new
opportunity to investigate the evolutionary link between these two different
neutron star manifestations. The remarkable X-ray variability and hard X-ray
spectrum of this object can potentially serve as a template to search for other
X-ray binary/radio pulsar transitional objects. Here we demonstrate that the
transient X-ray source XMM J174457-2850.3 near the Galactic center displays
similar X-ray properties. We report on the detection of an energetic
thermonuclear burst with an estimated duration of ~2 hr and a radiated energy
output of ~5E40 erg, which unambiguously demonstrates that the source harbors
an accreting neutron star. It has a quiescent X-ray luminosity of Lx~5E32 erg/s
and exhibits occasional accretion outbursts during which it brightens to
Lx~1E35-1E36 erg/s for a few weeks (2-10 keV). However, the source often
lingers in between outburst and quiescence at Lx~1E33-1E34 erg/s. This unusual
X-ray flux behavior and its relatively hard X-ray spectrum, a power law with an
index of ~1.4, could possibly be explained in terms of the interaction between
the accretion flow and the magnetic field of the neutron star.

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The categories of this paper are: eess
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The categories of this paper are: q-bio
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: q-alg
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The categories of this paper are: cond-mat
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The categories of this paper are: comp-gas
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The categories of this paper are: ao-sci
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The categories of this paper are: solv-int
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The categories of this paper are: cs
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The categories of this paper are: chao-dyn
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The categories of this paper are: atom-ph
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The categories of this paper are: stat
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The categories of this paper are: nucl-th
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The categories of this paper are: gr-qc