Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: 2MASS wide field extinction maps: IV. The Orion, Mon R2, Rosette, and
  Canis Major star forming regions   We present a near-infrared extinction map of a large region (approximately
2200 deg^2) covering the Orion, the Monoceros R2, the Rosette, and the Canis
Major molecular clouds. We used robust and optimal methods to map the dust
column density in the near-infrared (NICER and NICEST) towards ~19 million
stars of the Two Micron All Sky Survey (2MASS) point source catalog. Over the
relevant regions of the field, we reached a 1-sigma error of 0.03 mag in the
K-band extinction with a resolution of 3 arcmin. We measured the cloud
distances by comparing the observed density of foreground stars with the
prediction of galactic models, thus obtaining d_{Orion A} = (371 +/- 10) pc,
d_{Orion B} = (398 +/- 12) pc, $d_{Mon R2} = (905 +/- 37) pc, $d_{Rosette} =
(1330 +/- 48) pc, and $d_{CMa} = (1150 +/- 64) pc, values that compare very
well with independent estimates.

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The categories of this paper are: nucl-ex
8
The categories of this paper are: hep-ex
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
35
The categories of this paper are: mtrl-th
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
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The categories of this paper are: acc-phys
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The categories of this paper are: q-alg
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The categories of this paper are: nlin