Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Discovery of periodic class II methanol masers associated with
  G339.986-0.425 region   Ten new class II methanol masers from the 6.7-GHz Methanol Multibeam survey
catalogues III and IV were selected for a monitoring programme at both 6.7 and
12.2 GHz with the 26m Hartebeesthoek Radio Astronomy Observatory (HartRAO)
radio telescope for two years and nine months, from August 2012 to May 2015. In
the sample, only masers associated with G339.986-0.425 were found to show
periodic variability at both 6.7 and 12.2 GHz. The existence of periodic
variation was tested with four independent methods. The analytical method gave
the best estimation of the period, which was 246 $\pm$ 1 days. The time series
of G339.986-0.425 show strong correlations across velocity channels and between
the 6.7 and 12.2 GHz masers. The time delay was also measured across channels
and shows structure across the spectrum which is continuous between different
maser components.

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The categories of this paper are: nucl-th
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The categories of this paper are: supr-con
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The categories of this paper are: atom-ph
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The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
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The categories of this paper are: hep-ex
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The categories of this paper are: bayes-an
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The categories of this paper are: mtrl-th
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The categories of this paper are: adap-org
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The categories of this paper are: plasm-ph
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The categories of this paper are: cs
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The categories of this paper are: comp-gas
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The categories of this paper are: solv-int
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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: math