Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Discovery of Diffuse Radio Polarization Structures in the NVSS   We have developed a method for recovering polarization structures from the
NRAO Very Large Array Sky Survey (NVSS) on larger angular scales than the
nominal 15 arc minute survey limit. The technique depends on the existence of
smaller scale fluctuations in polarization angle, to which the interferometer
is sensitive, while the undetected total intensity of the structures can be
arbitrarily large. We recover the large scale structure of the polarized Milky
Way, as seen in single dish surveys, as well as a wide variety of smaller scale
galactic and extragalactic features. We present a brief discussion of the
uncertainties and limitations of the reprocessed NVSS polarization survey, a
comparison of single-dish and NVSS results, and a sampling of the new
polarization structures. We show a companion feature 1.8 Mpc outside of Abell
cluster 3744, apparent Mpc-scale extensions to the tailed radio galaxy 3C31, a
possible new giant galactic loop,and a new bright polarized patch in supernova
remnant CTA1. We note that there is little quantitative information from these
detections, and followup investigations would be necessary to measure reliable
polarized fluxes and position angles. Some of the new features discovered in
this NVSS reanalysis could provide a foreground for CMB polarization studies,
but the internal foreground modeling for the next generation of experiments
should have no difficulty accounting for them.

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The categories of this paper are: comp-gas
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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
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
0
The categories of this paper are: hep-ph
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The categories of this paper are: q-fin
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The categories of this paper are: hep-lat
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The categories of this paper are: hep-th
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The categories of this paper are: atom-ph
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The categories of this paper are: supr-con
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The categories of this paper are: math-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: nlin
2
The categories of this paper are: math