DISK CORONA INTERACTION: MECHANISM FOR THE DISK TRUNCATION AND SPECTRUM CHANGE IN LOW-LUMINOSITY ACTIVE GALACTIC NUCLEI

	DISK CORONA INTERACTION: MECHANISM FOR THE DISK TRUNCATION AND SPECTRUM CHANGE IN LOW-LUMINOSITY ACTIVE GALACTIC NUCLEI
	Taam, Ronald E.1,2; Liu, B. F.3 ; Yuan, W.3 ; Qiao, E.3
刊名	ASTROPHYSICAL JOURNAL
	2012-11-01
卷号	759 期号:1
关键词	accretion, accretion disks black hole physics galaxies: active X-rays: galaxies
英文摘要	The truncation of an optically thick, geometrically thin accretion disk is investigated in the context of low-luminosity AGNs (LLAGNs). We generalize the disk evaporation model used in the interpretative framework of black hole X-ray binaries by including the effect of a magnetic field in accretion disks surrounding supermassive black holes. The critical transition mass accretion rate for which the disk is truncated is found to be insensitive to magnetic effects, but its inclusion leads to a smaller truncation radius in comparison to a model without its consideration. That is, a thin viscous disk is truncated for LLAGNs at an Eddington ratio less than 0.03 for a standard viscosity parameter (alpha = 0.3). An increase of the viscosity parameter results in a higher critical transition mass accretion rate and a correspondingly smaller truncation distance, the latter accentuated by greater magnetic energy densities in the disk. Based on these results, the truncation radii inferred from spectral fits of LLAGNs published in the literature are consistent with the disk evaporation model. The infrared emission arising from the truncated geometrically thin accretion disks may be responsible for the red bump seen in such LLAGNs.
收录类别	SCI
语种	英语
WOS记录号	WOS:000310566900065
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/6274]
专题	国家天文台_空间科学研究部
作者单位	1.Acad Sinica, Inst Astron & Astrophys, TIARA, Taipei 10617, Taiwan 2.Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA 3.Chinese Acad Sci, Natl Astron Observ, Beijing 100012, Peoples R China
推荐引用方式 GB/T 7714	Taam, Ronald E.,Liu, B. F.,Yuan, W.,et al. DISK CORONA INTERACTION: MECHANISM FOR THE DISK TRUNCATION AND SPECTRUM CHANGE IN LOW-LUMINOSITY ACTIVE GALACTIC NUCLEI[J]. ASTROPHYSICAL JOURNAL,2012,759(1).
APA	Taam, Ronald E.,Liu, B. F.,Yuan, W.,&Qiao, E..(2012).DISK CORONA INTERACTION: MECHANISM FOR THE DISK TRUNCATION AND SPECTRUM CHANGE IN LOW-LUMINOSITY ACTIVE GALACTIC NUCLEI.ASTROPHYSICAL JOURNAL,759(1).
MLA	Taam, Ronald E.,et al."DISK CORONA INTERACTION: MECHANISM FOR THE DISK TRUNCATION AND SPECTRUM CHANGE IN LOW-LUMINOSITY ACTIVE GALACTIC NUCLEI".ASTROPHYSICAL JOURNAL 759.1(2012).