Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The active RS CVn-type system SZ Pictoris   We study the short and long-term variability of the spectroscopic binary SZ
Pictoris, a southern RS CVn-type system. We used mid-resolution echelle spectra
obtained at CASLEO spanning 18 years, and photometric data from the ASAS
database V-band and from the Optical Robotic Observatory (BVRI-bands) for
similar time lapses. We separated the composite spectra into those
corresponding to both components, and we were able to determine accurate
orbital parameters, in particular an orbital period of 4.95 days. We also
observed a photometric modulation with half the orbital period, due to the
ellipticity of the stars. We also found cyclic activity with a period of ~ 2030
days, both in the photometry and in the Ca II flux of the secondary star of the
system.

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The categories of this paper are: cs
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The categories of this paper are: funct-an
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The categories of this paper are: physics
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The categories of this paper are: hep-ex
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The categories of this paper are: ao-sci
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The categories of this paper are: plasm-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: hep-th
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The categories of this paper are: adap-org
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The categories of this paper are: q-alg
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The categories of this paper are: mtrl-th
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The categories of this paper are: dg-ga
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The categories of this paper are: cond-mat
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The categories of this paper are: math
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The categories of this paper are: eess
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The categories of this paper are: nlin