Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Molecular Environment and an X-ray Spectroscopy of Supernova Remnant
  Kesteven 78   We investigate the molecular environment of the Galactic supernova remnant
(SNR) Kesteven 78 and perform an XMM-Newton X-ray spectroscopic study for the
northeastern edge of the remnant. SNR Kes78 is found to interact with the
molecular clouds (MCs) at a systemic local standard of rest velocity of 81km/s.
At around this velocity, the SNR appears to contact a long molecular strip in
the northeast and a large cloud in the east as revealed in the 13CO line, which
may be responsible for the radio brightness peak and the OH maser,
respectively. The 12CO-line bright region morphologically matches the eastern
bright radio shell in general, and the SNR is consistent in extent with a CO
cavity. Broadened 12CO line profiles discerned in the eastern maser region and
the western clumpy molecular arc and the elevated 12CO J=2-1/J=1-0 ratios along
the SNR boundary may be signatures of shock perturbation in the molecular gas.
The SNR-MC association places the SNR at a kinematic distance of 4.8 kpc. The
X-rays arising from the northeastern radio shell are emitted by underionized
hot (~1.5 keV), low-density (~0.1 cm^{-3}) plasma with solar abundance, and the
plasma may be of intercloud origin. The age of the remnant is inferred to be
about 6 kyr. The size of the molecular cavity in Kes78 implies an initial mass
around 22Msun for the progenitor.

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The categories of this paper are: patt-sol
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The categories of this paper are: comp-gas
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The categories of this paper are: nucl-ex
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The categories of this paper are: math-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: physics
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The categories of this paper are: funct-an
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The categories of this paper are: stat
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The categories of this paper are: hep-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: gr-qc
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The categories of this paper are: chem-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: q-bio
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The categories of this paper are: hep-ex
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The categories of this paper are: atom-ph