Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Interstellar Environment of Filled-Center Supernova Remnants: II.
  G63.7+1.1   A multi-wavelength investigation of the candidate supernova remnant G63.7+1.1
and its surrounding interstellar medium is presented. On the basis of radio
continuum data we conclude that the object is a filled-center supernova
remnant, perhaps in the course of becoming a composite remnant. The morphology
of the remnant, along with HI, 12CO and high resolution IRAS data, suggest that
G63.7+1.1 is interacting directly with the ISM, and does not lie in a low
density region of the ISM. This in turn strongly suggests that the detected
nebula is not surrounded by an invisible halo of supernova ejecta. The
association between the SNR and HI and CO features near the tangent point
implies a kinematic distance for G63.7+1.1 of 3.8 +/- 1.5 kpc.

25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
18
The categories of this paper are: econ
1
The categories of this paper are: cs
3
The categories of this paper are: physics
9
The categories of this paper are: nlin
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
4
The categories of this paper are: cond-mat
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex