Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Spatial Extent of (U)LIRGs in the Mid-Infrared. II. Feature Emission   We present results from the second part of our analysis of the extended
mid-infrared (MIR) emission of the Great Observatories All-Sky LIRG Survey
(GOALS) sample based on 5-14 micron low-resolution spectra obtained with the
IRS on Spitzer. We calculate the fraction of extended emission as a function of
wavelength for all galaxies in the sample, FEE_lambda, and spatially separate
the MIR spectrum of galaxies into their nuclear and extended components.
  We find that the [NeII] emission line is as compact as the hot dust MIR
continuum, while the polycyclic aromatic hydrocarbon (PAH) emission is more
extended. The 6.2 and 7.7 micron PAH emission is more compact than that of the
11.3 micron PAH, which is consistent with the formers being enhanced in a more
ionized medium. The presence of an AGN or a powerful nuclear starburst
increases the compactness of the hot dust MIR continuum, but has a negligible
effect on the spatial extent of the PAH emission on kpc-scales. Globally, the
spectra of the extended emission component are homogeneous for all galaxies in
GOALS. This suggests that the physical properties of star formation taking
place at distances farther than 1.5 kpc from the nuclei of (U)LIRGs are very
similar, resembling local star-forming galaxies with L_IR < 10^11 Lsun, as well
as star formation-dominated ULIRGs at z~2. In contrast, the MIR spectra of the
nuclear component of local (U)LIRGs are very diverse. This implies that the
observed variety of their integrated MIR properties arise, on average, only
from the processes that are taking place in their cores.

10
The categories of this paper are: q-bio
24
The categories of this paper are: dg-ga
21
The categories of this paper are: adap-org
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
13
The categories of this paper are: quant-ph
23
The categories of this paper are: solv-int
19
The categories of this paper are: eess
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
32
The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
4
The categories of this paper are: cond-mat