MagneticallyArrestedandMulti-phaseCircumbinaryAccretionaroundSupermassiveBlackHoleBina_dxwang仰望星空

个人资料

微博

正文字体大小：大中小

MagneticallyArrestedandMulti-phaseCircumbinaryAccretionaroundSupermassiveBlackHoleBina

(2025-01-02 08:48:26)

Magnetically Arrested and Multi-phase Circumbinary Accretion around Supermassive

Black Hole Binaries

Mon, Dec 23 2024, 10:30 am Jiangwan

发布者：曹欢发布时间：2024-12-16：

Abstract: Supermassive black hole (SMBH) binaries are expected to be a key focus of next-

generation gravitational wave detectors. Observations confirm that most galaxies harbor an

SMBH at their centers; therefore, SMBH binaries are a natural consequence of galaxy mergers.

The merger-induced enhancement of the gaseous core typically suggests that the SMBH binary

will be surrounded by a gaseous structure called a circumbinary disk. Using the GPU-enabled

version of the Athena++ code, AthenaK, we recently conducted a series of 3D magnetohydro-

dynamics simulations. We propose the concept of Magnetically Arrested (MAD) Circumbinary

Accretion when the separation of the SMBH binary is small. In this scenario, the tidally opened

cavity is filled with vertically oriented strong magnetic fields, and the disk periodically ejects

magnetic flux tubes, similar to the MAD state observed for a single black hole in general relativis-

tic MHD simulations. To connect our findings with potential observations, we carried out simula-

tions where the SMBH binary spirals inward and merges following the post-Newtonian approxi-

mation. We demonstrate that this MAD state is inevitable for all SMBH binaries before merger

and that corresponding electromagnetic signals may be observable. Additionally, we present a

separate suite of simulations that zoom in from galactic scales to sub-parsec scales, showing for

the first time the formation of a multi-phase, multi-scale circumbinary accretion flow self-

consistently formed from large-scale accretion. Bio: Haiyang Wang is a graduate student in the Department of Physics at California Institute of

Technology, before which he obtained his bachelor in Physics from Fudan University in 2022 and

master in Applied Mathematics from University of Cambridge in 2023. He in interested in black

hole (binaries), galaxy evolution, gravitational wave sources and their EM counterparts, numerical

simulations especially GPU computing and machine learning.

阅读┊ 收藏 ┊ 喜欢 ▼ ┊打印┊举报/Report