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arXiv · 1706.02049

A $γ$-ray Quasi-Periodic modulation in the Blazar PKS 0301$-$243?

Peng-Fei Zhang·Da-Hai Yan·Jia-Neng Zhou·Yi-Zhong Fan·Jian-Cheng Wang·Li Zhang
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Abstract

We report a nominally high-confidence $γ$-ray quasi-periodic modulation in the blazar PKS 0301$-$243. For this target, we analyze its \emph{Fermi}-LAT Pass 8 data covering from 2008 August to 2017 May. Two techniques, i.e., the maximum likelihood optimization and the exposure-weighted aperture photometry, are used to build the $γ$-ray light curves. Then both the Lomb-Scargle Periodogram and the Weighted Wavelet Z-transform are applied to the light curves to search for period signals. A quasi-periodicity with a period of $2.1\pm0.3$ yr appears at the significance level of $\sim5σ$, although it should be noted that this putative quasi-period variability is seen in a data set barely four times longer. We speculate that this $γ$-ray quasi-periodic modulation might be evidence of a binary supermassive black hole.

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Peng-Fei Zhang, Da-Hai Yan, Jia-Neng Zhou, Yi-Zhong Fan, Jian-Cheng Wang, Li Zhang. 2017-07-06. A $γ$-ray Quasi-Periodic modulation in the Blazar PKS 0301$-$243?. https://doi.org/10.3847/1538-4357%2Faa7ecd

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