On the morphological dichotomies observed in the powerful radio galaxies

Frontiers in Theoretical and Applied Physics/UAE 2017

Miraghaei, H.^1 ; Best, P.N.^2

School of Astronomy, Institute for Research in Fundamental Sciences, PO Box 19395-5531, Tehran, Iran^1

Institute for Astronomy (IfA), University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh

EH9 3HJ, United Kingdom^2

关键词: Compact sources;    Extended sources;    Host galaxies;    Massive black holes;    Optical spectra;    Radio galaxies;    Radio sources;    Type II;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/869/1/012078/pdf
DOI  :  10.1088/1742-6596/869/1/012078

来源: IOP

【 摘 要 】

We study environment and host galaxy properties of powerful radio galaxies with different radio morphologies from compact sources to very extended double lobed radio galaxies and with different optical spectra classified as high excitation (HERG; quasar-mode) and low excitation (LERG; jet-mode) radio galaxies. We use a complete sample of morphologically classified radio sources from [1] and perform three different analyses: i) we compare compact radio sources with the extended sources from the same class of excitation. ii) we compare HERGs with the LERGs using a combined sample of compact and extended sources. iii) we investigate the origin of different morphologies observed in the very extended powerful radio galaxies, historically classified as Fanaroff-Riley (FR) radio galaxies of type I and type II by comparing a sample of FRIs with the FRIIs from the same excitation class. We discuss the results and what causes the differences in each comparison. The role of host galaxy and the central super massive black hole, and the galaxy interactions are all investigated.