Comparison between Fermi detected and non-Fermi detected superluminal sources  

作　　者：HuBing Xiao JunHui Fan JiangHe Yang Yi Liu YuHai Yuan Jun Tao Denise Costantin YuTao Zhang ZhiYuan Pei LiXia Zhang WenXin Yang 

机构地区：[1]Center for Astrophysics,Guangzhou University,Guangzhou 510006,China [2]Department of Physics and Astronomy,University of Padova,Padova PD 35131,Italy [3]Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province,Guangzhou 510006,China [4]Department of Physics and Electronics Science,Hunan University of Arts and Science,Changde 415000,China [5]Shanghai Astronomical Observatory,Chinese Academy of Sciences,Shanghai 210006,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2019年第12期110-125,共16页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.11733001,U1531245,10633010,11173009,and11403006);the Natural Science Foundation of Guangdong Province(Grant No.2017A030313011);the Astrophysics Key Subjects of Guangdong Province and Guangzhou City;the Science and Technology Program of Guangzhou(Grant No.201707010401)

摘　　要：Active galactic nuclei（AGNs） have been attracting research attention due to their special observable properties. Specifically,a majority of AGNs are detected by Fermi-LAT missions, but not by Fermi-LAT, which raises the question of weather any differences exist between the two. To answer this issue, we compile a sample of 291 superluminal AGNs（189 FDSs and 102 nonFDSs） from available multi-wavelength radio, optical, and X-ray（or even γ-ray） data and Doppler factors and proper motion（μ）(or apparent velocity(βapp)); calculated the apparent velocity from their proper motion, Lorentz factor（Γ）, viewing angle（?） and co-moving viewing angle(?co) for the sources with available Doppler factor（δ）; and performed some statistical analyses for both types. Our study indicated that（1） in terms of average values, FDSs have higher proper motions（μ）, apparent velocities(βapp),Doppler factor（δ）, Lorentz factor（Γ）, and smaller viewing angle（?）. Nevertheless, there is no clear difference in co-moving viewing angles（?∞）. The results reveal that FDSs show stronger beaming effect than non-FDSs.（2） In terms of correlations:1) both sources show positive, mutually correlated fluxes, which become closer in de-beamed fluxes; 2) with respect to apparent velocities and γ-ray luminosity, there is a tendency for the brighter sources to have higher velocities; 3) with regard to viewing angle and observed γ-ray luminosity, log? =-（0.23 ± 0.04）log Lγ+（11.14 ± 1.93）, while for the co-moving viewing angle and the intrinsic γ-ray luminosity, log?∞=（0.09 ± 0.01）log Lγn-（1.73 ± 0.48）. These correlations show that the luminous γ-ray sources have smaller viewing angles and a larger co-moving viewing angle, which indicate a stronger beaming effect in γ-ray emissions.Active galactic nuclei(AGNs) have been attracting research attention due to their special observable properties. Specifically,a majority of AGNs are detected by Fermi-LAT missions, but not by Fermi-LAT, which raises the question of weather any differences exist between the two. To answer this issue, we compile a sample of 291 superluminal AGNs(189 FDSs and 102 nonFDSs) from available multi-wavelength radio, optical, and X-ray(or even γ-ray) data and Doppler factors and proper motion(μ)(or apparent velocity(βapp));calculated the apparent velocity from their proper motion, Lorentz factor(Γ), viewing angle(Ф) and co-moving viewing angle(Фco) for the sources with available Doppler factor(δ);and performed some statistical analyses for both types. Our study indicated that(1) in terms of average values, FDSs have higher proper motions(μ), apparent velocities(βapp),Doppler factor(δ), Lorentz factor(Γ), and smaller viewing angle(Ф). Nevertheless, there is no clear difference in co-moving viewing angles(Ф∞). The results reveal that FDSs show stronger beaming effect than non-FDSs.(2) In terms of correlations:1) both sources show positive, mutually correlated fluxes, which become closer in de-beamed fluxes;2) with respect to apparent velocities and γ-ray luminosity, there is a tendency for the brighter sources to have higher velocities;3) with regard to viewing angle and observed γ-ray luminosity, logФ=-(0.23 ± 0.04)log Lγ+(11.14 ± 1.93), while for the co-moving viewing angle and the intrinsic γ-ray luminosity, logФ∞=(0.09 ± 0.01)log Lγ^in-(1.73 ± 0.48). These correlations show that the luminous γ-ray sources have smaller viewing angles and a larger co-moving viewing angle, which indicate a stronger beaming effect in γ-ray emissions.

关 键 词：active GALACTIC NUCLEI jets γ-rays CORRELATIONS 

分 类 号：P15[天文地球—天文学]