发表机构
Johns Hopkins University; University of Pennsylvania; NASA Goddard Space Flight Center（约翰斯·霍普金斯大学; 宾夕法尼亚大学; 美国宇航局戈达德太空飞行中心）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
通过辐射MHD模拟发现，物理冷却通过增强磁场改变环绕双星盘结构，消除密度团块并增加内边缘偏心率。
AI 中文摘要
辐射压和辐射冷却在决定天体物理对象的结构和动力学中往往起着重要作用。在本文中，我们展示了围绕等质量超大质量双黑洞（SMBBH）的环绕双星盘（CBD）的辐射磁流体动力学（MHD）模拟。该模拟采用基于局部热力学平衡和扩散冷却的近似热力学模型，该模型能够捕捉光学厚区域中内能如何演化。在$r=5a$范围内，盘达到准稳态，其质量分布与未包含物理热力学过程的模拟结果存在显著差异：方位角平均表面密度中的局部极大值和团块被完全消除；时间平均内边缘变得更加偏心；垂直密度分布强烈依赖于半径。这些变化归因于冷却驱动的盘垂直压缩导致的磁场增强。我们的结果强调，内部CBD的基本性质对辐射和磁物理都敏感。
英文摘要
Radiation pressure and radiative cooling often play an important role in deciding the structure and dynamics of astrophysical objects. In this paper, we present a radiative MHD simulation of a circumbinary disk (CBD) around an equal-mass SMBBH. It employs an approximate thermodynamic model based on local thermodynamic equilibrium and diffusion cooling which captures how the internal energy evolves in an optically thick region. The disk reaches a quasi-steady state within $r=5a$ whose mass distribution differs substantially from the one obtained from simulations without physical thermodynamics: the local maximum in the azimuthally-averaged surface density and the lump are completely erased; the time-averaged inner edge becomes more eccentric; and the vertical density distribution depends strongly on the radius. These changes are attributable to the enhancement of the magnetic fields caused by the cooling-driven vertical compression of the disk. Our result emphasizes that the basic properties of the inner CBD are sensitive to both radiation and magnetic physics.
Comments23 pages, 14 figures
