Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Detection of Possible Quasi-periodic Oscillations in the Long-term
  Optical Light Curve of the BL Lac Object OJ 287   Detection of periodicity in the broad-band non-thermal emission of blazars
has so far been proven to be elusive. However, there are a number of scenarios
which could lead to quasi-periodic variations in blazar light curves. For
example, orbital or thermal/viscous period of accreting matter around central
supermassive black holes could, in principle, be imprinted in the
multi-wavelength emission of small-scale blazar jets, carrying as such crucial
information about plasma conditions within the jet launching regions. In this
paper, we present the results of our time series analysis of $\sim 9.2$
year-long, and exceptionally well-sampled optical light curve of the BL Lac OJ
287. The study primarily uses the data from our own observations performed at
the Mt. Suhora and Krak\'ow Observatories in Poland, and at the Athens
Observatory in Greece. Additionally, SMARTS observations were used to fill in
some of the gaps in the data. The Lomb-Scargle Periodogram and the Weighted
Wavelet Z-transform methods were employed to search for the possible QPOs in
the resulting optical light curve of the source. Both the methods consistently
yielded possible quasi-periodic signal around the periods of $\sim 400$ and
$\sim 800$ days, the former one with a significance (over the underlying
colored noise) of $\geq 99\%$. A number of likely explanations for such are
discussed, with a preference given to a modulation of the jet production
efficiency by highly magnetized accretion disks. This supports the previous
findings and the interpretation reported recently in the literature for OJ 287
and other blazar sources.

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The categories of this paper are: nucl-th
1
The categories of this paper are: cs
24
The categories of this paper are: dg-ga
37
The categories of this paper are: supr-con
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The categories of this paper are: nucl-ex
4
The categories of this paper are: cond-mat
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The categories of this paper are: cmp-lg
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-th
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The categories of this paper are: q-bio
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The categories of this paper are: eess
8
The categories of this paper are: hep-ex
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The categories of this paper are: math-ph
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The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
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The categories of this paper are: plasm-ph