GLOBAL COMPTON HEATING AND COOLING IN HOT ACCRETION FLOWS

	GLOBAL COMPTON HEATING AND COOLING IN HOT ACCRETION FLOWS
	Yuan, Feng1 ; Xie, Fuguo1,2 ; Ostriker, Jeremiah P.3
刊名	ASTROPHYSICAL JOURNAL
	2009-01-20
卷号	691 期号:1 页码:98-104
关键词	accretion black hole physics galaxies: active quasars: general X-rays: general accretion disks
英文摘要	The hot accretion flow ( such as advection-dominated accretion flow) is usually optically thin in the radial direction, therefore the photons produced at one radius can travel for a long distance without being absorbed. These photons can thus heat or cool electrons at other radii via Compton scattering. This effect has been ignored in most previous works on hot accretion flows and is the focus of this paper. If the mass accretion rate is described by. (M) over dot = (M) over dot (0)(r/r(out))(0.3) and r(out) = 10(4)r(s), we find that the Compton scattering will play a cooling and heating role at r less than or similar to 5 x 10(3)r(s) and r greater than or similar to 5 x 10(3)r(s), respectively. Specifically, when (M) over dot (0) > 0.1L(Edd)/c(2), the Compton cooling rate is larger than the local viscous heating rate at certain radius; therefore the cooling effect is important. When (M) over dot (0) > 2L(Edd)/c(2), the heating effect at r(out) is important. We can obtain the self-consistent steady solution with the global Compton effect included only if (M) over dot (0) less than or similar to L(Edd)/c(2) for r(out) = 50r(s), which corresponds to L less than or similar to 0.02L(Edd). Above this rate the Compton cooling is so strong at the inner region that hot solutions cannot exist. On the other hand, for r(out) = 10(5)r(s), we can only get the self-consistent solution when (M) over dot (0) less than or similar to L(Edd)/c(2) and L < 0.01L(Edd). The value of this critical accretion rate is anticorrelated with the value of r(out). Above this accretion rate, the equilibrium temperature of electrons at r(out) is higher than the virial temperature as a result of strong Compton heating, so the accretion is suppressed. In this case the activity of the black hole will likely "oscillate" between an active and an inactive phase, with the oscillation timescale being the radiative timescale of the gas at r(out).
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]	ADVECTION-DOMINATED ACCRETION ; ACTIVE GALACTIC NUCLEI ; MASSIVE BLACK-HOLES ; X-RAY SOURCES ; SEYFERT-GALAXIES ; BINARY-SYSTEMS ; SAGITTARIUS-A ; QUASARS ; LUMINOSITY ; SPECTRUM
收录类别	SCI
语种	英语
WOS记录号	WOS:000263196600010
公开日期	2010-11-08
内容类型	期刊论文
源URL	[http://119.78.226.72//handle/331011/12647]
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, Shanghai 200030, Peoples R China 2.Chinese Acad Sci, Grad Sch, Beijing 100039, Peoples R China 3.Princeton Univ Observ, Princeton, NJ 08544 USA
推荐引用方式 GB/T 7714	Yuan, Feng,Xie, Fuguo,Ostriker, Jeremiah P.. GLOBAL COMPTON HEATING AND COOLING IN HOT ACCRETION FLOWS[J]. ASTROPHYSICAL JOURNAL,2009,691(1):98-104.
APA	Yuan, Feng,Xie, Fuguo,&Ostriker, Jeremiah P..(2009).GLOBAL COMPTON HEATING AND COOLING IN HOT ACCRETION FLOWS.ASTROPHYSICAL JOURNAL,691(1),98-104.
MLA	Yuan, Feng,et al."GLOBAL COMPTON HEATING AND COOLING IN HOT ACCRETION FLOWS".ASTROPHYSICAL JOURNAL 691.1(2009):98-104.