论文标题
无碰撞积聚到黑洞上：动态和耀斑
Collisionless accretion onto black holes: dynamics and flares
论文作者
论文摘要
我们使用轴对称的一般偏见粒子模拟研究了无碰撞等离子体从第一原理旋转的黑洞的积聚。我们对这些结果与类似的一般迁移式磁流体动力学模拟进行并排比较。尽管总体流动动力学有许多相似之处，但可以确定动力学模拟和流体模拟之间的三个关键差异。磁重新连接更有效，并在我们的动力学方法中迅速加速了非热粒子种群。此外，动力学模拟中的血浆与热平衡形成了显着偏离，包括激发动力学不稳定性的压力各向异性，以及在地平线附近的大型田间对准热通量接近自由流动值。我们讨论了结果对SGR A*和M87的模拟事件型观测的含义，并通过重力和事件地平线望远镜进行建模。
We study the accretion of collisionless plasma onto a rotating black hole from first principles using axisymmetric general-relativistic particle-in-cell simulations. We carry out a side-by-side comparison of these results to analogous general-relativistic magnetohydrodynamic simulations. Although there are many similarities in the overall flow dynamics, three key differences between the kinetic and fluid simulations are identified. Magnetic reconnection is more efficient, and rapidly accelerates a nonthermal particle population, in our kinetic approach. In addition, the plasma in the kinetic simulations develops significant departures from thermal equilibrium, including pressure anisotropy that excites kinetic-scale instabilities, and a large field-aligned heat flux near the horizon that approaches the free-streaming value. We discuss the implications of our results for modeling event-horizon scale observations of Sgr A* and M87 by GRAVITY and the Event Horizon Telescope.
