THE STRUCTURE AND SPECTRAL FEATURES OF A THIN DISK AND EVAPORATION-FED CORONA IN HIGH-LUMINOSITY ACTIVE GALACTIC NUCLEI

	THE STRUCTURE AND SPECTRAL FEATURES OF A THIN DISK AND EVAPORATION-FED CORONA IN HIGH-LUMINOSITY ACTIVE GALACTIC NUCLEI
	Liu JY(刘杰英)1,2 ; Liu, BF3 ; Qiao, EL3 ; Mineshige, S 4
刊名	ASTROPHYSICAL JOURNAL
	2012-08-01
卷号	754 期号:2
关键词	accretion, accretion disks galaxies: active X-rays: galaxies
ISSN号	0004-637X
通讯作者	Liu, JY (reprint author), Chinese Acad Sci, Natl Astron Observ, Yunnan Observ, Kunming 650011, Peoples R China.
产权排序	第一完成单位
英文摘要	We investigate the accretion process in high-luminosity active galactic nuclei (HLAGNs) in the scenario of the disk evaporation model. Based on this model, the thin disk can extend down to the innermost stable circular orbit (ISCO) at accretion rates higher than 0.02(M) over dot(Edd) while the corona is weak since part of the coronal gas is cooled by strong inverse Compton scattering of the disk photons. This implies that the corona cannot produce as strong X-ray radiation as observed in HLAGNs with large Eddington ratio. In addition to the viscous heating, other heating to the corona is necessary to interpret HLAGN. In this paper, we assume that a part of accretion energy released in the disk is transported into the corona, heating up the electrons, and is thereby radiated away. For the first time, we compute the corona structure with additional heating, fully taking into account the mass supply to the corona, and find that the corona could indeed survive at higher accretion rates and that its radiation power increases. The spectra composed of bremsstrahlung and Compton radiation are also calculated. Our calculations show that the Compton-dominated spectrum becomes harder with the increase of energy fraction (f) liberating in the corona, and the photon index for hard X-ray (2-10 keV) is 2.2 < Gamma < 2.7. We discuss possible heating mechanisms for the corona. Combining the energy fraction transported to the corona with the accretion rate by magnetic heating, we find that the hard X-ray spectrum becomes steeper at a larger accretion rate and the bolometric correction factor (L-bol/L2-10keV) increases with increasing accretion rate for f < 8/35, which is roughly consistent with the observational results.
学科主题	Astronomy & Astrophysics
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	ADVECTION-DOMINATED ACCRETION ; RADIATION-MAGNETOHYDRODYNAMIC SIMULATIONS ; RECONNECTION-HEATED CORONA ; X-RAY BINARIES ; BLACK-HOLE ; ENERGY-DISTRIBUTIONS ; SEYFERT-GALAXIES ; MAGNETIC-FIELD ; SAGITTARIUS-A ; FLOWS
收录类别	SCI
原文出处	http://iopscience.iop.org/article/10.1088/0004-637X/754/2/81/meta
语种	英语
WOS记录号	WOS:000306666700002
内容类型	期刊论文
源URL	[http://ir.ynao.ac.cn/handle/114a53/5219]
专题	云南天文台_恒星物理研究组云南天文台_中国科学院天体结构与演化重点实验室
作者单位	1.National Astronomical Observatories/Yunnan Observatory, Chinese Academy of Sciences, Kunming 650011, China 2.Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences, Kunming 650011, China 3.National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China 4.Department of Astronomy, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
推荐引用方式 GB/T 7714	Liu JY,Liu, BF,Qiao, EL,et al. THE STRUCTURE AND SPECTRAL FEATURES OF A THIN DISK AND EVAPORATION-FED CORONA IN HIGH-LUMINOSITY ACTIVE GALACTIC NUCLEI[J]. ASTROPHYSICAL JOURNAL,2012,754(2).
APA	Liu JY,Liu, BF,Qiao, EL,&Mineshige, S.(2012).THE STRUCTURE AND SPECTRAL FEATURES OF A THIN DISK AND EVAPORATION-FED CORONA IN HIGH-LUMINOSITY ACTIVE GALACTIC NUCLEI.ASTROPHYSICAL JOURNAL,754(2).
MLA	Liu JY,et al."THE STRUCTURE AND SPECTRAL FEATURES OF A THIN DISK AND EVAPORATION-FED CORONA IN HIGH-LUMINOSITY ACTIVE GALACTIC NUCLEI".ASTROPHYSICAL JOURNAL 754.2(2012).