Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Deep Near Infrared Observations of the X-ray Emitting Class 0 Protostar
  Candidates in the Orion Molecular Cloud-3   We obtained near infrared (NIR) imaging with the Subaru Telescope of the
class 0 protostar candidates in the Orion Molecular Cloud-3, two of which were
discovered to have X-ray emission by the Chandra X-ray Observatory. We found
strong evidence for the class~0 nature of the X-ray sources. First, our deep
K-band image shows no emission brighter than 19.6 mag from both of these X-ray
sources. Since class I protostars or class II T Tauri stars should be easily
detected in the NIR with this sensitivity, the lack of K-band detection
suggests that they are likely much more obscured than class I protostars.
Second, our H2 v=1-0 S(1) image shows a bubble-like feature from one of the
X-ray class 0 protostar candidates, which reinforces the idea that this is a
class 0 protostar. We also discuss the nature of nine NIR sources found in our
deep image based on their colors, spatial coincidence with millimeter cores,
and the properties of their X-ray counterparts.

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The categories of this paper are: plasm-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: mtrl-th
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The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
5
The categories of this paper are: gr-qc
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The categories of this paper are: hep-th
20
The categories of this paper are: acc-phys
4
The categories of this paper are: cond-mat
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The categories of this paper are: math-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: adap-org
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The categories of this paper are: q-bio
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The categories of this paper are: nlin
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The categories of this paper are: cs
0
The categories of this paper are: hep-ph