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arXiv · 1909.06177

The relationship between the radio core-dominance parameter and spectral index in different classes of extragalactic radio sources (III)

Zhi-Yuan Pei·Jun-Hui Fan·Denis Bastieri·Jiang-He Yang·Hu-Bing Xiao·W. X. Yang
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Abstract

Active galactic nuclei (AGNs) can be divided into two major classes, namely radio-loud and radio-quiet AGNs. A small subset of the radio-loud AGNs is called blazars, which are believed to be unified with Fanaroff-Riley type I and type II (FRI&II) radio galaxies. Following our previous work, we present a latest sample of 966 sources with measured radio flux densities of the core and extended components. The sample includes 83 BL Lacs, 473 FSRQs, 101 Seyferts, 245 galaxies, 52 FRIs&IIs and 12 unidentified sources. We then calculate the radio core-dominance parameters and spectral indices and study their relationship. Our analysis shows that the core-dominance parameters and spectral indices are quite different for different types of sources. We also corroborate that the correlation between core-dominance parameter and radio spectral index extends over all the sources in a large sample presented.

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Zhi-Yuan Pei, Jun-Hui Fan, Denis Bastieri, Jiang-He Yang, Hu-Bing Xiao, W. X. Yang. 2019-09-12. The relationship between the radio core-dominance parameter and spectral index in different classes of extragalactic radio sources (III). https://doi.org/10.1088/1674-4527/20/2/25

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