Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Magnetic Field in the central parsec of the Galaxy   We present a polarisation map of the warm dust emission from the minispiral
in the central parsec of the Galactic centre. The observations were made at a
wavelength of 12.5 microns with CanariCam mounted on the 10.4-m Gran Telescopio
Canarias. The magnetic field traced by the polarised emission from aligned dust
grains is consistent with previous observations, but the increased resolution
of the present data reveals considerably more information on the detailed
structure of the B field and its correspondence with the filamentary emission
seen in both mid-infrared continuum emission and free-free emission at cm
wavelengths. The magnetic field appears to be compressed and pushed by the
outflows from luminous stars in the Northern Arm, but it is not disordered by
them. We identify some magnetically coherent filaments that cross the Northern
Arm at a Position Angle of ~45 degrees, and which may trace orbits inclined to
the primary orientation of the Northern Arm and circumnuclear disk. In the
East-West bar, the magnetic fields implied by the polarization in the lower
intensity regions lie predominantly along the bar at a Position Angle of 130 -
140 degrees. In contrast to the Northern Arm, the brighter regions of the bar
tend to have lower degrees of polarization with a greater divergence in
position angle compared to the local diffuse emission. It appears that the
diffuse emission in the East-West bar traces the underlying field and that the
bright compact sources are unrelated objects presumably projected onto the bar
and with different field orientations

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The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
4
The categories of this paper are: cond-mat
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
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The categories of this paper are: funct-an
3
The categories of this paper are: physics
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The categories of this paper are: q-fin
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The categories of this paper are: adap-org
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-th
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-ex