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arXiv · 1611.04354

Revisiting Quasi-Periodic modulation in $γ$-ray Blazar PKS 2155-304 with Fermi Pass 8 data

Pengfei Zhang·Dahai Yan·Nenghui Liao·Jiancheng Wang
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Abstract

We examine the gamma-ray quasi-periodic variability of PKS 2155-304 with the latest publicly available \emph{Fermi}-LAT Pass 8 data which covers the years from 2008 August to 2016 October. We produce the light curves in two ways, i.e., the exposure-weighted aperture photometry and the maximum likelihood optimization. The light curves are then analyzed by using Lomb-Scargle Periodogram (LSP) and Weighted Wavelet Z-transform (WWZ); and the results reveal a significant quasi-periodicity with a period of $1.74\pm0.13$ years and a significance of $\sim$ 4.9 $σ$. The constraint of multifrequencies quasi-periodic variabilities on blazar emission model is discussed.

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Pengfei Zhang, Dahai Yan, Nenghui Liao, Jiancheng Wang. 2017-01-04. Revisiting Quasi-Periodic modulation in $γ$-ray Blazar PKS 2155-304 with Fermi Pass 8 data. https://doi.org/10.3847/1538-4357%2F835%2F2%2F260

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