Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic activity analysis for a sample of G-type main sequence
  \emph{Kepler} targets   The variation of a stellar light curve owing to the rotational modulation by
the magnetic features (starspots and faculae) on the star's surface can be used
to investigate the magnetic properties of the host star. In this paper, we use
the periodicity and magnitude of the light-curve variation, as two proxies,
suggested by (He et al. 2015), to study the stellar magnetic properties for a
large sample of G-type main sequence \emph{Kepler} targets, for which the
rotation periods recently determined by (McQuillan et al. 2014). By analyzing
the correlation between the two magnetic proxies, it is found that: (1) The two
proxies are positively correlated for most of the stars in our sample, and the
percentages of negative, zero, and positive correlation are $4.27\%$, $6.81\%$,
and $88.91\%$, respectively; (2) Negative correlation stars cannot have large
magnitude of light-curve variation; (3) with the increase of rotation period,
the relative number of positive correlation stars decreases and the negative
correlation one increases. These results indicate that the stars with shorter
rotation period tend to have positive correlation between the two proxies, and
a good portion of the positive correlation stars have larger magnitude of
light-curve variation (and hence more intense magnetic activities) than the
negative correlation stars.

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The categories of this paper are: acc-phys
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The categories of this paper are: q-alg
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The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
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The categories of this paper are: plasm-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: atom-ph
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The categories of this paper are: eess
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The categories of this paper are: chem-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: quant-ph
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The categories of this paper are: supr-con
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The categories of this paper are: cs
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The categories of this paper are: hep-ph
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The categories of this paper are: math
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The categories of this paper are: nlin