论文标题
斑点形成和从辐射效率低下的积聚流量围绕巨大黑洞的射出
Blob formation and ejection from the radiative inefficient accretion flow around massive black hole
论文作者
论文摘要
我们通过2D磁性水力动力学（MHD）数值模拟研究了辐射性低效率无效的积聚流动的小规模磁重新连接，以模拟SGR a*的积聚流量的斑点形成和弹出。研究了新兴磁场和预先存在的磁场的连接，以检查是否可以在黑洞积聚盘的环境中驱动斑点。磁连接后，等离子体的速度和温度都可以与观察到的斑点射精底部的推断物理特性相媲美。插图，选择位于中央黑洞40个Schwarzschild Radii之内的三个小盒子作为我们的模拟区域。在重新连接开始时，由于重力吸引力，将流体朝向中央黑洞拉动，而重新连接产生的当前纸也朝着相同的方向拉动，因此，所产生的流出向上和向对称轴移动。最终，出现了巨大的斑点，它支持了情节喷射的灾难模型\ citep {2009mnras.395.2183y}。还发现，磁连接发生的距离越靠近黑洞，磁能的转化效率越高。对于这些内部斑点，由于K-H的不稳定性，它们具有涡流结构，沿当前纸进行以不同的速度分离流体。
We study the small scale magnetic reconnection above the radiative inefficient accretion flow around massive black hole via 2D magnetohydrodynamics (MHD) numerical simulation, in order to model the blob formation and ejection from the accretion flow around Sgr A*. The connection of both the newly emerging magnetic field and the pre-existing magnetic field is investigated to check whether blobs could be driven in the environment of black hole accretion disc. After the magnetic connection, both the velocity and temperature of the plasma can be comparable to the inferred physical properties at the base of the observed blob ejection. For illustration, three small boxes which are located within 40 Schwarzschild radii from the central black hole are chosen as our simulation areas. At the beginning of the reconnections, the fluid is pulled toward the central black hole due to the gravitational attraction and the current sheet produced by the reconnection is also pulled toward the same direction, consequently, the resulting outflows move both upwards and towards the symmetry axis of the central black hole. Eventually, huge blobs appear, which supports the catastrophe model of episodic jets \citep{2009MNRAS.395.2183Y}. It is also found that the closer to the black hole the magnetic connection happens, the higher the converting efficiency of the magnetic energy into the heat and kinetic energy. For these inner blobs, they have vortex structure due to the K-H instability, which happens along the current sheet separating the fluids with different speed.
