Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Infrared Imaging Polarimetry of Massive Star-forming Regions   Imaging polarimetry is a useful tool to reveal the 3D structure of dust
distributions and to localize embedded young stellar objects. We present maps
of the linear polarization at 2.2 micron for three ultra-compact HII regions
(G192.16-3.82, G331.28-0.19, G339.88-1.26) and the methanol maser source
G305.21+0.21. From the polarization maps, we draw conclusions on the morphology
of these objects and the presence of luminous illuminating sources.

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The categories of this paper are: eess
9
The categories of this paper are: nlin
3
The categories of this paper are: physics
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
36
The categories of this paper are: cmp-lg
16
The categories of this paper are: stat
2
The categories of this paper are: math
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
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The categories of this paper are: adap-org
35
The categories of this paper are: mtrl-th
11
The categories of this paper are: hep-lat
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The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con