Influence of the magnetic coupling process on advection-dominated accretion flows around black holes

	Influence of the magnetic coupling process on advection-dominated accretion flows around black holes
	Ma, Ren-Yi 1,2,3; Yuan, Feng1,2,3 ; Wang, Ding-Xiong 4
刊名	ASTROPHYSICAL JOURNAL
	2007-12-20
卷号	671 期号:2 页码:1981-1989
关键词	accretion black hole physics magnetic fields accretion disks
英文摘要	A large-scale closed magnetic field can transfer angular momentum and energy between a black hole (BH) and its surrounding accretion flow. We investigate the effects of this magnetic coupling (MC) process on the dynamics of a hot accretion flow (e. g., an advection-dominated accretion flow). The energy and angular momentum fluxes transported by the magnetic field are derived with an equivalent-circuit approach. For a rapidly rotating BH, it is found that the radial velocity and the electron temperature of the accretion flow decrease, whereas the ion temperature and the surface density increase. The significance of the MC effects depends on the value of the viscosity parameter alpha. The effects are obvious for alpha = 0.3 but nearly ignorable for alpha = 0.1. For a BH with specific angular momentum a(*) = 0.9 and alpha = 0.3, we find that for reasonable parameters the radiative efficiency of a hot accretion flow can be increased by similar to 30%.
学科主题	星系与宇宙学研究中心
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	X-RAY BINARIES ; FORCE-FREE MAGNETOSPHERE ; RELATIVISTIC ACCRETION ; EXTRACTING ENERGY ; DISK-ACCRETION ; SAGITTARIUS-A ; NEUTRON-STAR ; LUMINOSITY ; FIELD ; GEOMETRY
收录类别	SCI
语种	英语
WOS记录号	WOS:000253331600070
公开日期	2010-11-08
内容类型	期刊论文
源URL	[http://119.78.226.72//handle/331011/12641]
专题	上海天文台_星系宇宙学重点实验室
作者单位	1.Chinese Acad Sci, Shanghai Astron Observ, Beijing 100864, Peoples R China 2.Shanghai Astron Observ, Joint Inst Galaxy & Cosmol, Shanghai, Peoples R China 3.Univ Sci & Technol China, Shanghai 200030, Peoples R China 4.Huazhong Univ Sci & Technol, Dept Phys, Wuhan 430074, Peoples R China
推荐引用方式 GB/T 7714	Ma, Ren-Yi,Yuan, Feng,Wang, Ding-Xiong. Influence of the magnetic coupling process on advection-dominated accretion flows around black holes[J]. ASTROPHYSICAL JOURNAL,2007,671(2):1981-1989.
APA	Ma, Ren-Yi,Yuan, Feng,&Wang, Ding-Xiong.(2007).Influence of the magnetic coupling process on advection-dominated accretion flows around black holes.ASTROPHYSICAL JOURNAL,671(2),1981-1989.
MLA	Ma, Ren-Yi,et al."Influence of the magnetic coupling process on advection-dominated accretion flows around black holes".ASTROPHYSICAL JOURNAL 671.2(2007):1981-1989.