Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Evidence for an oscillation of the magnetic axis of the white dwarf in
  the polar DP Leonis   From 1979 to 2001, the magnetic axis of the white dwarf in the polar DP Leo
slowly rotated by 50 deg in azimuth, possibly indicating a small asynchronism
between the rotational and orbital periods of the magnetic white dwarf. We have
obtained phase-resolved orbital light curves between 2009 and 2013, which show
that this trend has not continued in recent years. Our data are consistent with
the theoretically predicted oscillation of the magnetic axis of the white dwarf
about an equilibrium orientation, which is defined by the competition between
the accretion torque and the magnetostatic interaction of the primary and
secondary star. Our data indicate an oscillation period of ~60 yr, an amplitude
of about 25 deg, and an equilibrium orientation leading the connecting line of
the two stars by about 7 deg.

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The categories of this paper are: solv-int
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The categories of this paper are: eess
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The categories of this paper are: hep-lat
25
The categories of this paper are: patt-sol
4
The categories of this paper are: cond-mat
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
15
The categories of this paper are: nucl-ex
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The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
13
The categories of this paper are: quant-ph
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The categories of this paper are: q-fin
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The categories of this paper are: chao-dyn