Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Chandra X-ray Observatory Detection of Extended X-ray Emission from the
  Planetary Nebula BD+303639   We report the detection of well resolved, extended X-ray emission from the
young planetary nebula BD+303639 using the Advanced CCD Imaging Spectrometer
(ACIS) aboard the Chandra X-ray Observatory. The X-ray emission from BD+303639
appears to lie within, but is concentrated to one side of, the interior of the
shell of ionized gas seen in high-resolution optical and IR images. The
relatively low X-ray temperature (Tx ~ 3x10^6 K) and asymmetric morphology of
the X-ray emission suggests that conduction fronts are present and/or mixing of
shock-heated and photoionized gas has occurred and, furthermore, hints at the
presence of magnetic fields. The ACIS spectrum suggests that the X-ray emitting
region is enriched in the products of helium burning. Our detection of extended
X-ray emission from BD+303639 demonstrates the power and utility of Chandra
imaging as applied to the study of planetary nebulae.

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The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
2
The categories of this paper are: math
3
The categories of this paper are: physics
16
The categories of this paper are: stat
26
The categories of this paper are: bayes-an
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
15
The categories of this paper are: nucl-ex
28
The categories of this paper are: alg-geom
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
35
The categories of this paper are: mtrl-th
9
The categories of this paper are: nlin
10
The categories of this paper are: q-bio
4
The categories of this paper are: cond-mat