Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic Fields in Star-Forming Molecular Clouds IV. Polarimetry of the
  Filamentary NGC 2068 Cloud in Orion B   We present submillimeter polarimetry at 850 micron toward the filamentary
star-forming region associated with the reflection nebulosity NGC 2068 in Orion
B. These data were obtained using the James Clerk Maxwell Telescope's SCUBA
polarimeter. The polarization pattern observed is not consistent with that
expected for a field geometry defined by a single mean field direction. There
are three distinct distributions of polarization angle, which could represent
regions of differing inclination and/or field geometry within the filamentary
gas. In general, the polarization pattern does not correlate with the
underlying total dust emission. The presence of varying inclinations against
the plane of the sky is consistent with the comparison of the 850 micron
continuum emission to the optical emission from the Palomar Optical Sky Survey,
which shows that the western dust emission lies in the foreground of the
optical nebula while the eastern dust emission originates in the background.
Percentage polarizations are high, particularly toward the north-east region of
the cloud. The mean polarization percentage in the region is 5.0% with a
standard deviation of 3.1%. Depolarization toward high intensities is
identified in all parts of the filament.

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The categories of this paper are: acc-phys
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The categories of this paper are: eess
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The categories of this paper are: hep-th
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The categories of this paper are: alg-geom
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The categories of this paper are: math-ph
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The categories of this paper are: solv-int
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The categories of this paper are: q-alg
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The categories of this paper are: funct-an
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The categories of this paper are: math
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The categories of this paper are: q-bio
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The categories of this paper are: physics
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The categories of this paper are: comp-gas
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The categories of this paper are: ao-sci
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The categories of this paper are: chem-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: dg-ga