Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Diverse polarization angle swings from a repeating fast radio burst
  source   Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown
origin. Two possible mechanisms that could generate extremely coherent emission
from FRBs invoke neutron star magnetospheres or relativistic shocks far from
the central energy source. Detailed polarization observations may help us to
understand the emission mechanism. However, the available FRB polarization data
have been perplexing, because they show a host of polarimetric properties,
including either a constant polarization angle during each burst for some
repeaters or variable polarization angles in some other apparently one-off
events. Here we report observations of 15 bursts from FRB 180301 and find
various polarization angle swings in seven of them. The diversity of the
polarization angle features of these bursts is consistent with a magnetospheric
origin of the radio emission, and disfavours the radiation models invoking
relativistic shocks.

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The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
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The categories of this paper are: eess
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The categories of this paper are: alg-geom
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The categories of this paper are: adap-org
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The categories of this paper are: hep-ex
4
The categories of this paper are: cond-mat
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The categories of this paper are: stat
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The categories of this paper are: hep-lat
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The categories of this paper are: chao-dyn
5
The categories of this paper are: gr-qc
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The categories of this paper are: q-fin