Unification of Radio Galaxies and their Accretion Jet Properties

Journal of astrophysics and astronomy

Qingwen Wu1³  Xinwu Cao²  Ya-Di Xu¹ 

[1] Physics Department, Shanghai Jiao Tong University, Shanghai, China.$$;Shanghai Astronomical Observatory, CAS, Shanghai, China.$$;Physics Department, Huazhong University of Science and Technology, Wuhan, China.$$

关键词: Black hole physics;    accretion;    galaxies: jets.;   

DOI  :  

学科分类：天文学(综合)

来源: Indian Academy of Sciences

【 摘 要 】

We investigate the relation between black hole mass, 𝑀bh, and jet power, 𝑄jet, for a sample of BL Lacs and radio quasars. We find that BL Lacs are separated from radio quasars by the FR I/II dividing line in 𝑀bh-𝑄jet plane, which strongly supports the unification scheme of FR I/BL Lac and FR II/radio quasar. The Eddington ratio distribution of BL Lacs and radio quasars exhibits a bimodal nature with a rough division at 𝐿bol/𝐿Edd ∼ 0.01, which imply that they may have different accretion modes. We calculate the jet power extracted from advection-dominated accretion flow (ADAF), and find that it requires dimensionless angular momentum of black hole 𝑗 ≃ 0.9 - 0.99 to reproduce the dividing line between FR I/II or BL Lac/radio quasar if dimensionless accretion rate $dot{m} = 0.01$ is adopted, which is required by the above bimodal distribution of Eddington ratios. Our results suggest that black holes in radio galaxies are rapidly spinning.

【 授权许可】

Unknown