Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Chandra Observations of Diffuse Gas and Luminous X-ray Sources Around
  the X-ray Bright Elliptical NGC 1600   (Abridged) We observed the X-ray bright E3 galaxy NGC 1600 and nearby group
members with the Chandra X-ray Observatory ACIS S3. Unresolved emission
dominates the observation; however, we resolved some emission into 71 sources,
most of which are low-mass X-ray binaries (LMXBs) associated with NGC 1600.
Twenty-one sources have L_X>2E39 ergs/s (0.3-10.0 keV; assuming they are at the
distance of NGC 1600) marking them as ultraluminous X-ray point source (ULX)
candidates; we expect only 11+/-2 are unrelated sources. NGC 1600 may have the
largest number of ULX candidates in an early-type galaxy to date; however,
cosmic variance in the number of background AGN cannot be ruled out. There are
indications that there are also a large number of unresolved point sources. We
propose that these are associated with globular clusters (GCs), and that NGC
1600 has a large GC specific frequency. The unresolved emission appears to have
two gas components. We interpret the soft inner component (a<~25", kT~0.85 keV)
as the interstellar medium of NGC 1600 and the hotter outer component (a>~25",
kT~1.5 keV) as the intragroup medium of the NGC 1600 group. The X-ray image
shows several interesting structures, excess emission roughly cospatial with
H$\alpha$ and dust filaments, possible holes in the X-ray emission roughly
coincident with radio lobes, excess emission to the northeast possibly
indicating the center of the group potential, and a tail of X-ray emission from
the group galaxy NGC 1603 probably due to ram-pressure stripping

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The categories of this paper are: q-fin
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The categories of this paper are: q-bio
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The categories of this paper are: chao-dyn
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The categories of this paper are: supr-con
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The categories of this paper are: hep-ex
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The categories of this paper are: acc-phys
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The categories of this paper are: solv-int
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The categories of this paper are: physics
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The categories of this paper are: alg-geom
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The categories of this paper are: math
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-th
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The categories of this paper are: patt-sol
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The categories of this paper are: nucl-ex
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The categories of this paper are: mtrl-th
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The categories of this paper are: chem-ph