Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: One, two or three stars? An investigation of an unusual eclipsing binary
  candidate undergoing dramatic period changes   We report our investigation of 1SWASP J234401.81-212229.1, a variable with a
18461.6 s period. After identification in a 2011 search of the SuperWASP
archive for main-sequence eclipsing binary candidates near the distribution's
short-period limit of approx. 0.20 d, it was measured to be undergoing rapid
period decrease in our earlier work, though later observations supported a
cyclic variation in period length. Spectroscopic data obtained in 2012 with the
Southern African Large Telescope did not, however, support the interpretation
of the object as a normal eclipsing binary. Here, we consider three possible
explanations consistent with the data: a single-star oblique rotator model in
which variability results from stable cool spots on opposite magnetic poles; a
two-star model in which the secondary is a brown dwarf; and a three-star model
involving a low-mass eclipsing binary in a hierarchical triple system. We
conclude that the latter is the most likely model.

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The categories of this paper are: q-alg
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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: chao-dyn
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-th
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The categories of this paper are: math-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: stat
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The categories of this paper are: nlin
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-ex
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The categories of this paper are: patt-sol
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The categories of this paper are: q-fin
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The categories of this paper are: eess