Superluminal Motion and Polarization in Blazars

A relativistic beaming model has been successfully used to explain the observed properties of active galactic nuclei (AGNs). In this model there are two emission components, a boosted one and an unbeamed one, shown up in the radio band as the core and lobe components. The luminosity ratio of the core to the lobe is defined as the core-dominance parameter (R = LCore/LLobe) The de-beamed radio luminosity (Ldbjet) in the jet is assumed to be proportional to the unbeamed luminosity (Lub) in the co-moving frame, i.e., f = Ldbjet/Lub and f is determined in our previous paper. We further discuss the relationship between BL Lacertae objects(BLs) and flat spectrum radio quasars (FSRQs), which are subclasses of blazars with different degrees of polarization, using the calculated values of the ratio f for a sample of superluminal blazars. We found 1) that the BLs show smaller averaged Doppler factors and Lorentz factors, larger viewing angles and higher coredominance parameters than do the FSRQs, and 2) that in the polarization-core dominance parameter plot (P - log R) the BLs and FSRQs occupy a scattered region, but in a revised plot (logP/c(m) - logR), they gather around two different lines, suggesting that they have some different intrinsic properties.

作 者： Jun-Hui Fan Yong-Jiu Wang Jiang-He Yang Cheng-Yue Su   作者單位： Jun-Hui Fan(Center for Astrophysics, Guangzhou University, Guangzhou,510400;Physics Institute, Hunan Normal University, Changsha)

Yong-Jiu Wang(Physics Institute, Hunan Normal,University, Changsha)

Jiang-He Yang(Department of Electronics and Physics, Hunan University of Arts and Science, Changde,415000)

Cheng-Yue Su(Department of Physics, Guangdong Industry University, Guangzhou) 

刊 名： 天體物理學報（英文版）  ISTIC SCI 英文刊名： CHINESE JOURNAL OF ASTRONOMY AND ASTROPHYSICS  年，卷(期)： 2004 4(6)  分類號： P14  關鍵詞： active galactic nuclei - superluminal motion - jets - relativistic beaming model