合并残留物中的双黑洞。一：将吸积与动力学联系起来
Dual black holes in merger remnants. I: linking accretion to dynamics
摘要：
本文研究了旋转支撑的环核盘中大质量黑洞对的轨道演化和吸积历史，直到大质量黑洞形成双星系统。我们的模拟具有高分辨率的质量和空间，这是第一次，使得它可行的轨道衰变的MBH无论是反或同向旋转相对于环核盘。我们表明，一个移动的MBH在一个最初的反旋转轨道上经历了“轨道角动量翻转”，由于气体动力学摩擦，即，它在MBH二进制形成之前开始与盘共转。我们强调，这种效应只能在非常高分辨率的模拟中捕获。考虑到使用的气体粒子数量非常大，动力学范围足够大，可以解决单个MBH的Bondi-Hoyle-Lyttleton半径。因此，我们能够连接的吸积过程的MBH对的轨道演化。我们预测，吸积率是显着抑制和极其可变的MBH是在逆行轨道上移动时。只有在轨道角动量翻转发生后，次级粒子才会迅速“点亮”，此时两个MBH都可以在爱丁顿速率附近吸积几百万年。在这个阶段，双核的分离预计约为10 pc。我们表明，吸积率可以是高度可变的，也当MBH是共同旋转的光盘（虽然在较小的程度上），其轨道是偏心的。我们的研究结果有显着的预期数量的可观测到的双重活动星系核分离的<100 pc的后果。
英文摘要：
We study the orbital evolution and accretion history of massive black hole (MBH) pairs in rotationally supported circumnuclear discs up to the point where MBHs form binary systems. Our simulations have high resolution in mass and space which, for the first time, makes it feasible to follow the orbital decay of a MBH either counter- or co-rotating with respect to the circumnuclear disc. We show that a moving MBH on an initially counter-rotating orbit experiences an "orbital angular momentum flip" due to the gas-dynamical friction, i.e., it starts to corotate with the disc before a MBH binary forms. We stress that this effect can only be captured in very high resolution simulations. Given the extremely large number of gas particles used, the dynamical range is sufficiently large to resolve the Bondi-Hoyle-Lyttleton radii of individual MBHs. As a consequence, we are able to link the accretion processes to the orbital evolution of the MBH pairs. We predict that the accretion rate is significantly suppressed and extremely variable when the MBH is moving on a retrograde orbit. It is only after the orbital angular momentum flip has taken place that the secondary rapidly "lights up" at which point both MBHs can accrete near the Eddington rate for a few Myr. The separation of the double nucleus is expected to be around ~10 pc at this stage. We show that the accretion rate can be highly variable also when the MBH is co-rotating with the disc (albeit to a lesser extent) provided that its orbit is eccentric. Our results have significant consequences for the expected number of observable double AGNs at separations of <100 pc.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
