Can the formation of x-ray-obscuring tori and jets in active galaxies be determined by one parameter?

被引:2
作者
Blackman, EG [1 ]
Yi, IS [1 ]
机构
[1] INST ADV STUDY,PRINCETON,NJ 08540
关键词
galaxies; active; jets; magnetic fields; radio continuum;
D O I
10.1086/309995
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
A torus of reduced differential rotation can form in the inner less than or similar to 10 pc core of active galactic nuclei (AGNs), incurring a density enhancement that can account for obscuration of X-rays in Seyfert galaxies when the initial inner core-to-black hole mass ratio is greater than or similar to 50. The same density enhancement can also lead to dynamo growth of significant poloidal magnetic fields when accreted onto the central engine. Since radio jet models often employ poloidal fields as agents in extracting power for the jet luminosity, we suggest that jetted AGNs might require this poloidal field production. Although the poloidal field would originally be produced in the obscuring torus, jetted objects could exist without obscuring tori: The poloidal field would only aid in powering jet emission after it accretes with the torus matter to the central engine. Thus, only during the relatively short torus accretion timescale could there be both a jet and a torus.
引用
收藏
页码:L21 / L24
页数:4
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