2D MHD simulations of the state transitions of XRay binaries taking into account thermal conduction

Kenji E. Nakamura, Mami Machida, Ryoji Matsumoto

研究成果: ジャーナルへの寄稿記事

1 引用 (Scopus)

抄録

Thermal conduction plays an important role in bimodal accretion flows consisting of hightemperature flow and cool flow, especially when the temperature is high and/or has a steep gradient. For example, in hard-to-soft transitions of black hole accretion flows, thermal conduction between the high-temperature region and the low-temperature region is appropriately considered. We conducted two-dimensional magnetohydrodynamic (MHD) numerical simulations considering anisotropic heat conduction to study condensation of geometrically thick hot accretion flows driven by radiative cooling during state transitions. Numerical results show that the intermediate region appears between the hot corona and the cool accretion disk when we consider heat conduction. The typical temperature and number density of the intermediate region of the 10M black hole at Rg 10 (6 Rg = 3.0 ×106 cm is the Schwarzschild radius) are 4 × T 10 10 < T [K] < 4 × 1012 and 5×1015 < n [cm-3] < 5×1017, respectively. The thickness of intermediate region is about half of the radius. By comparing two models with or without thermal conduction, we demonstrate the effects of thermal conduction.

元の言語英語
記事番号22
ジャーナルGalaxies
7
発行部数1
DOI
出版物ステータス出版済み - 1 21 2019

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magnetohydrodynamic simulation
conduction
conductive heat transfer
radii
accretion disks
magnetohydrodynamics
coronas
condensation
cooling
gradients
simulation

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics

これを引用

2D MHD simulations of the state transitions of XRay binaries taking into account thermal conduction. / Nakamura, Kenji E.; Machida, Mami; Matsumoto, Ryoji.

:: Galaxies, 巻 7, 番号 1, 22, 21.01.2019.

研究成果: ジャーナルへの寄稿記事

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