论文标题
费米·布拉兹（Fermi Blazars）的长期光学和红外变异性特征
Long term optical and infrared variability characteristics of Fermi Blazars
论文作者
论文摘要
我们介绍了{\ it fermi gamma-ray空间望远镜}在$γ$ ray频段中检测到的37个BLAZAR的长期光学和近红外通量可变性分析。其中，有30个是扁平频谱无线电类星体（FSRQ），其中7个是BL LAC对象（BL LACS）。光学数据（BVR）和红外线（JK）频段来自2008年$ -2018之间的小型和中等孔径研究望远镜系统。从不同波长的光曲线的互相关分析中，我们没有发现在不同波长处的变化之间的显着延迟，除了三个来源，即PKS 1144 $ -379，PKS B1424 $ - $ 418和3C 273。 （$σ_m$）在J波段中，与B波段大于B波段，与热积聚盘组件上非热喷气机的优势一致。考虑到FSRQ和BL LAC作为样本，有符合$σ_m$的迹象，以逐渐增加两者的较长波长，但是发现仅在FSRQ中B和J波段之间具有统计学意义。在b $ - $ j v/s j颜色幅度图中，我们注意到复杂的光谱变异性模式。当更明亮（RWB）行为时，大多数对象显示出红色。当更明亮（BWB）趋势时，很少有物体显示出蓝色，而在某些物体中，BWB和RWB行为都被注意到。这些结果涉及通量和颜色特征，表明FSRQ和BL LAC的射流发射是无法区分的。
We present long term optical and near infrared flux variability analysis of 37 blazars detected in the $γ$-ray band by the {\it Fermi Gamma-Ray Space Telescope}. Among them, 30 are flat spectrum radio quasars (FSRQs) and 7 are BL Lac objects (BL Lacs). The photometric data in the optical (BVR) and infrared (JK) bands were from the Small and Moderate Aperture Research Telescope System acquired between 2008$-$2018. From cross-correlation analysis of the light curves at different wavelengths, we did not find significant time delays between variations at different wavelengths, except for three sources, namely PKS 1144$-$379, PKS B1424$-$418 and 3C 273. For the blazars with both B and J-band data, we found that in a majority of FSRQs and BL Lacs, the amplitude of variability ($σ_m$) in the J-band is larger than B-band consistent with the dominance of the non-thermal jet over the thermal accretion disc component. Considering FSRQs and BL Lacs as a sample, there are indications of $σ_m$ to increase gradually towards longer wavelengths in both, however, found to be statistically significant only between B and J-bands in FSRQs. In the B$-$J v/s J colour magnitude diagram, we noticed complicated spectral variability patterns. Most of the objects showed a redder when brighter (RWB) behaviour. Few objects showed a bluer when brighter (BWB) trend, while in some objects both BWB and RWB behaviours were noticed. These results on flux and colour characteristics indicate that the jet emission of FSRQs and BL Lacs is indistinguishable.
