Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: RX J1039.7-0507: A New Intermediate Polar and Probable Recent Nova,
  possessing a large Reflection Effect   The ROSAT source RX J1039.7-0507, known from its optical spectrum to be a
Cataclysmic Variable star, is shown from high speed photometry to have an
orbital period of 1.574 h. The system has a nearly sinusoidal photometric
modulation with a range of 1.1 mag which we interpret as the reflection effect
caused by a very hot white dwarf primary. This suggests that a nova explosion
occured on the primary in the relatively recent past. In addition, RX
J1039.7-0507 has periodic signals at 1932.5 s and 721.9 s which, with the aid
of other periods present at low amplitude, we interpret as an orbital sideband
and the first harmonic of the primary's spin period. RX J1039.7-0507 is
therefore an intermediate polar with a spin period of 1444 s (24.07 min).

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The categories of this paper are: eess
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The categories of this paper are: nucl-th
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The categories of this paper are: math
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The categories of this paper are: nlin
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The categories of this paper are: chao-dyn
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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: supr-con
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The categories of this paper are: alg-geom
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The categories of this paper are: solv-int
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The categories of this paper are: mtrl-th
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The categories of this paper are: cond-mat
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The categories of this paper are: chem-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: adap-org
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The categories of this paper are: hep-th