Analytic Properties of Force-free Jets in the Kerr Spacetime. III. Uniform Field Solution

	Analytic Properties of Force-free Jets in the Kerr Spacetime. III. Uniform Field Solution
	Pan, Zhen 1; Yu C(余聪)2,3 ; Huang, Lei 4
刊名	ASTROPHYSICAL JOURNAL
	2017-02-20
卷号	836 期号:2
关键词	gravitation magnetic fields magnetohydrodynamics (MHD)
ISSN号	0004-637X
通讯作者	Pan, Zhen(Univ Calif Davis, Dept Phys, One Shields Ave, Davis, CA 95616 USA)
产权排序	第2完成单位
英文摘要	The structure of the steady axisymmetric force-free magnetosphere of a Kerr black hole (BH) is governed by a second-order partial differential equation of Af depending on two "free" functions Omega(A(phi)) and I(A(phi)), where A(phi) is the f component of the vector potential of the electromagnetic field, O is the angular velocity of the magnetic field lines, and I is the poloidal electric current. In this paper, we investigate the solution uniqueness. Taking the asymptotically uniform field as an example, analytic studies imply that there are infinitely many solutions approaching the uniform field at infinity, while only a unique one is found in general relativistic magnetohydrodynamic simulations. To settle the disagreement, we reinvestigate the structure of the governing equation and numerically solve it with given constraint and boundary conditions. We find that the constraint condition (field lines smoothly crossing the light surface) and boundary conditions at the horizon and at infinity are connected via radiation conditions at horizon and at infinity, rather than being independent. With appropriate constraint and boundary conditions, we numerically solve the governing equation and find a unique solution. Contrary to naive expectations, our numerical solution yields a discontinuity in the angular velocity of the field lines and a current sheet along the last field line crossing the event horizon. We also briefly discuss the applicability of the perturbation approach to solving the governing equation.
学科主题	天文学
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	BLANDFORD-ZNAJEK MECHANISM ; BLACK-HOLE MAGNETOSPHERES ; RELATIVISTIC MAGNETOHYDRODYNAMIC SIMULATIONS ; ACTIVE GALACTIC NUCLEI ; GAMMA-RAY BURSTS ; MAGNETIC-FIELD ; ACCRETION DISK ; ROTATIONAL ENERGY ; SCREW INSTABILITY ; PENROSE PROCESS
收录类别	SCI
原文出处	http://stacks.iop.org/0004-637X/836/i=2/a=193?key=crossref.d24c81b004025152d4ff73cc7b29a8be
语种	英语
WOS记录号	WOS:000395797900009
内容类型	期刊论文
源URL	[http://ir.ynao.ac.cn/handle/114a53/9987]
专题	云南天文台_大样本恒星演化研究组云南天文台_中国科学院天体结构与演化重点实验室
作者单位	1.Department of Physics, University of California, One Shields Avenue, Davis, CA 95616, USA 2.Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011, China 3.Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences, Kunming 650011, China 4.Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai, 200030, China
推荐引用方式 GB/T 7714	Pan, Zhen,Yu C,Huang, Lei. Analytic Properties of Force-free Jets in the Kerr Spacetime. III. Uniform Field Solution[J]. ASTROPHYSICAL JOURNAL,2017,836(2).
APA	Pan, Zhen,Yu C,&Huang, Lei.(2017).Analytic Properties of Force-free Jets in the Kerr Spacetime. III. Uniform Field Solution.ASTROPHYSICAL JOURNAL,836(2).
MLA	Pan, Zhen,et al."Analytic Properties of Force-free Jets in the Kerr Spacetime. III. Uniform Field Solution".ASTROPHYSICAL JOURNAL 836.2(2017).