Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spitzer observations of the N157B supernova remnant and its surroundings   (Aims): We study the LMC interstellar medium in the field of the nebula
N157B, which contains a supernova remnant, an OB association, ionized gas, and
high-density dusty filaments in close proximity. We investigate the relative
importance of shock excitation by the SNR and photo-ionization by the OB stars,
as well as possible interactions between the supernova remnant and its
environment. (Methods): We apply multiwavelength mapping and photometry, along
with spatially resolved infrared spectroscopy, to identifying the nature of the
ISM using new infrared data from the Spitzer space observatory and X-ray,
optical, and radio data from the literature. (Results): The N157B SNR has no
infrared counterpart. Infrared emission from the region is dominated by the
compact blister-type HII region associated with 2MASS J05375027-6911071 and
excited by an O8-O9 star. This object is part of an extended infrared emission
region that is associated with a molecular cloud. We find only weak emission
from the shock-indicator [FeII], and both the excitation and the heating of the
extended cloud are dominated by photo-ionization by the early O stars of LH99.
(Conclusions): Any possible impact by the expanding SNR does not now affect the
extended cloud of molecules and dust, despite the apparent overlap of SNR X-ray
emission with infrared and Ha emission from the cloud. This implies that the
supernova progenitor cannot have been more massive than about 25 solar masses.

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The categories of this paper are: cmp-lg
25
The categories of this paper are: patt-sol
3
The categories of this paper are: physics
7
The categories of this paper are: hep-th
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
19
The categories of this paper are: eess
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
1
The categories of this paper are: cs
21
The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ