Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The X-ray emission of 3C 346 and its environment   We present a detailed spectral and spatial analysis of the X-ray properties
of the compact and unusual radio galaxy 3C 346, combining information from
ROSAT and ASCA. The dominant component of X-ray emission (~ 10^44 ergs/s in
each of the 0.5-3 keV and 2-10 keV bands) is unresolved and not heavily
absorbed (intrinsic N_H ~< 2 10^21 cm^-2), with evidence for variability of 32
+/- 13% over 18 months. We relate the X-ray emission to radio structures on
both milliarcsecond scales and the arcsecond scales which Chandra can resolve.
The absence of X-ray absorption, and the radio/optical/X-ray colors, when
combined with previous radio evidence that the source is a foreshortened FRII,
suggest that the radio jets are seen at an angle to the line of sight of about
30 degrees, intermediate between the radio-galaxy and quasar classes. Roughly a
third of the soft X-ray emission is from a cluster atmosphere, for which we
measure a temperature of 1.9 (+1.3, -0.7) keV, making this the second
low-redshift (z < 0.2) powerful radio galaxy, after Cygnus A, with a measured
cluster temperature. At a jet angle of ~ 30 degrees, all the radio structures
lie within the core radius of the cluster, for which the cooling time is
sufficiently long that there is no reason to expect the presence of a cooling
flow. The radio lobes of 3C 346 are roughly in pressure balance with the
external medium under the assumptions that the energy densities in the magnetic
field and radiating particles balance and that a source of excess pressure in
the radio lobes, commonly invoked in other radio galaxies, is absent here.

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The categories of this paper are: adap-org
3
The categories of this paper are: physics
32
The categories of this paper are: atom-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: alg-geom
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The categories of this paper are: q-fin
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The categories of this paper are: gr-qc
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The categories of this paper are: nucl-ex
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The categories of this paper are: eess
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The categories of this paper are: solv-int
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The categories of this paper are: stat
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The categories of this paper are: chem-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: nucl-th
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The categories of this paper are: hep-ex
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The categories of this paper are: plasm-ph