Similarity of jet radiation between flat spectrum radio quasars and GeV narrow-line Seyfert 1 galaxies: a universal δ-Lc correlation  

作　　者：Yong-Kai Zhu Jin Zhang Hai-Ming Zhang En-Wei Liang Da-Hai Yan Wei Cui Shuang-Nan Zhang 

机构地区：[1]Guangxi Key Laboratory for Relativistic Astrophysics, Department of Physics, Guangxi University, Nanning 530004, China [2]Key Laboratory of Space Astronomy and Technology, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China [3]Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China [4]Department of Physics and Astronomy, Purdue University, West Lafayette, IN 47907, USA

出　　处：《Research in Astronomy and Astrophysics》2016年第11期43-52,共10页天文和天体物理学研究（英文版）

基　　金：supported by the National Basic Research Program of China (973 Program) (grant 2014CB845800);the National Natural Science Foundation of China (grants 11573034, 11533003, 11373036 and 11133002);the Strategic Priority Research Program “The Emergence of Cosmological Structures” of the Chinese Academy of Sciences (grant XDB09000000);the Guangxi Science Foundation (2013GXNSFFA019001)

摘　　要：By modeling the broadband spectral energy distributions （SEDs） of a typical flat spectrum radio quasar （FSRQ, 3C 279） and two GeV narrow-line Seyfert 1 galaxies （NLSls, PMN J0948＋0022 and 1H 0323＋342） in different flux stages with one-zone leptonic models, we find a universal correlation between their Doppler factors （δ） and peak luminosities （Lc） of external Compton scattering bumps. Compiling a combined sample of FSRQs and GeV NLSls, it is found that both FSRQs and GeV NLSls in different stages and in different sources follow the same δ-Lc correlation well. This indicates that the variations of observed luminosities may be essentially due to the Doppler boosting effect. The universal δ-Lo relation between FSRQs and GeV NLS 1 s in different stages may be further evidence that the particle acceleration and radiation mechanisms for the two kinds of sources are similar. In addition, by replacing Lc with the observed luminosity in the Fermi/LAT band （LLAT）, this correlation holds and it may serve as an empirical indicator of δ. We estimate the δ values with LLAT for 484 FSRQs in the Fermi/LAT Catalog and they range from 3 to 41, with a median of 16, which are statistically consistent with the values derived by other methods.By modeling the broadband spectral energy distributions （SEDs） of a typical flat spectrum radio quasar （FSRQ, 3C 279） and two GeV narrow-line Seyfert 1 galaxies （NLSls, PMN J0948＋0022 and 1H 0323＋342） in different flux stages with one-zone leptonic models, we find a universal correlation between their Doppler factors （δ） and peak luminosities （Lc） of external Compton scattering bumps. Compiling a combined sample of FSRQs and GeV NLSls, it is found that both FSRQs and GeV NLSls in different stages and in different sources follow the same δ-Lc correlation well. This indicates that the variations of observed luminosities may be essentially due to the Doppler boosting effect. The universal δ-Lo relation between FSRQs and GeV NLS 1 s in different stages may be further evidence that the particle acceleration and radiation mechanisms for the two kinds of sources are similar. In addition, by replacing Lc with the observed luminosity in the Fermi/LAT band （LLAT）, this correlation holds and it may serve as an empirical indicator of δ. We estimate the δ values with LLAT for 484 FSRQs in the Fermi/LAT Catalog and they range from 3 to 41, with a median of 16, which are statistically consistent with the values derived by other methods.

关 键 词：galaxies： active - galaxies： jets - quasars： general - galaxies： Seyfert 

分 类 号：P152[天文地球—天文学] P158