论文标题
高斯流程建模$ \ it {fermi} $ - lat $γ$ -Ray Blazar的可变性：带有$γ$ -Ray Quasi-periodicities的Blazars样本
Gaussian Process Modeling $\it{Fermi}$-LAT $γ$-ray Blazar Variability: A Sample of Blazars with $γ$-ray Quasi-periodicities
论文作者
论文摘要
Blazar的可变性可能是由随机过程驱动的。另一方面，最近据报道，在$ \ it {fermi} $ - Blazars的LAT数据中检测到了准周期振荡（QPO）行为。但是，仍然质疑这些QPO信号的重要性。我们分析了$γ$ - 雷射线的光曲线QPO Blazars使用两种高斯工艺方法，Carma和$ \ it {celerite} $，以研究高斯流程的适当性，以表征$γ$ - 射线光线的光线及Qpos的存在。我们收集了27种可能的$γ$ - 雷周期性的样本，并生成其$ \ sim11 $年$ \ it {fermi} $ - lat Light curves。我们将高斯工艺模型应用于$γ$ ray的光曲线，并构建其内在功率频谱密度（PSD）。结果表明，通常可以用Carma和$ \ textit {celerite} $型号来表征$γ$ - 射线光曲线，这表明$γ$ -Ray的差异能力本质上是高斯流程。最终的PSD通常是红色噪声形状，坡度在$ -0.6 $和$ -1.7 $之间。 PKS 0537 $ - $ 441和PG 1553 $+$ 113的$γ$ -Ray QPO的可能证据在高斯流程模型中找到。
Blazar variability may be driven by stochastic processes. On the other hand, quasi-periodic oscillation (QPO) behaviors are recently reported to be detected in $\it{Fermi}$-LAT data of blazars. However, the significances of these QPO signals given by traditional Fourier-like methods are still questioned. We analyze $γ$-ray light curves of the QPO blazars with two Gaussian process methods, CARMA and $\it{celerite}$, to examine the appropriateness of Gaussian processes for characterizing $γ$-ray light curves of blazars and the existence of the reported QPOs. We collect a sample of 27 blazars with possible $γ$-ray periodicity and generate their $\sim11$ years $\it{Fermi}$-LAT light curves. We apply the Gaussian process models to the $γ$-ray light curves, and build their intrinsic power spectral densities (PSDs). The results show that in general the $γ$-ray light curves can be characterized by CARMA and $\textit{celerite}$ models, indicating that $γ$-ray variabilities of blazars are essentially Gaussian processes. The resulting PSDs are generally the red noise shapes with slopes between $-0.6$ and $-1.7$. Possible evidence for the $γ$-ray QPOs in PKS 0537$-$441 and PG 1553$+$113 are found in the Gaussian process modelings.
