REVISITING THE THERMAL STABILITY OF RADIATION-DOMINATED THIN DISKS

CORC > 厦门大学 > 物理技术－已发表论文

	REVISITING THE THERMAL STABILITY OF RADIATION-DOMINATED THIN DISKS
	Zheng, S. M. ; Yuan, F. ; Gu, W. M. ; Lu, J. F. ; Gu WM(顾为民)
刊名	http://dx.doi.org/10.1088/0004-637X/732/1/52
	2011-05-01
关键词	HOLE ACCRETION DISKS 3-DIMENSIONAL MAGNETOHYDRODYNAMIC SIMULATIONS LIMIT-CYCLE BEHAVIOR BLACK-HOLE GALACTIC NUCLEI BINARY-SYSTEMS INSTABILITY TURBULENCE VARIABILITY EQUILIBRIA
英文摘要	National Basic Research Program of China [2009CB824800]; National Natural Science Foundation of China [10821302, 10825314, 10833002, 11073015]; CAS/SAFEA; The standard thin disk model predicts that when the accretion rate is over a small fraction of the Eddington rate, which corresponds to L greater than or similar to 0.06 L-Edd, the inner region of the disk is radiation-pressure dominated and thermally unstable. However, observations of the high/soft state of black hole X-ray binaries with luminosity well within this regime (0.01L(Edd) less than or similar to L less than or similar to 0.5L(Edd)) indicate that the disk has very little variability, i.e., it is quite stable. Recent radiation magnetohydrodynamic simulations of a vertically stratified shearing box have confirmed the absence of the thermal instability. In this paper, we revisit the thermal stability by linear analysis, taking into account the role of magnetic field in the accretion flow. By assuming that the field responds negatively to a positive temperature perturbation, we find that the threshold of accretion rate above which the disk becomes thermally unstable increases significantly compared with the case of not considering the role of magnetic field. This accounts for the stability of the observed sources with high luminosities. Our model also presents a possible explanation as to why only GRS 1915+105 seems to show thermally unstable behavior. This peculiar source holds the highest accretion rate (or luminosity) among the known high state sources, which is well above the accretion rate threshold of the instability.
语种	英语
内容类型	期刊论文
源URL	[http://dspace.xmu.edu.cn/handle/2288/70506]
专题	物理技术－已发表论文
推荐引用方式 GB/T 7714	Zheng, S. M.,Yuan, F.,Gu, W. M.,et al. REVISITING THE THERMAL STABILITY OF RADIATION-DOMINATED THIN DISKS[J]. http://dx.doi.org/10.1088/0004-637X/732/1/52,2011.
APA	Zheng, S. M.,Yuan, F.,Gu, W. M.,Lu, J. F.,&顾为民.(2011).REVISITING THE THERMAL STABILITY OF RADIATION-DOMINATED THIN DISKS.http://dx.doi.org/10.1088/0004-637X/732/1/52.
MLA	Zheng, S. M.,et al."REVISITING THE THERMAL STABILITY OF RADIATION-DOMINATED THIN DISKS".http://dx.doi.org/10.1088/0004-637X/732/1/52 (2011).