论文标题
局部模拟吸积盘上发光体上加热扭矩的模拟
Local Simulations of Heating Torques on a Luminous Body in an Accretion Disk
论文作者
论文摘要
嵌入积聚盘中的发光体可以产生不对称的密度扰动，从而导致净扭矩，从而导致人体的轨道迁移。线性理论表明，这种加热扭矩会导致人体质量中的迁移术语线性，从而反对甚至扭转了由引力lindblad和Co-Orbital Torques产生的。我们在未分层的磁盘中使用高分辨率的局部模拟来评估线性理论适用性的准确性和域。我们发现在适当的制度（低光度，低导热率）中，分析结果和仿真结果之间的一致性比10 \％好，但是测量非线性（高光度）状态的偏差以及高热电导率方案。在非线性方案中，线性理论高估了由于加热扭矩引起的加速度，这是由于热通量中非线性项的忽视所致。在高热电导率方案中，线性理论低估了加速度，尽管在这里非线性和计算约束都起作用。我们讨论了加热扭矩对原星磁盘中低质量行星进化的影响，以及大量恒星或积聚嵌入AGN磁盘中的紧凑物体的影响。对于后一种情况，我们表明热扭矩可能是磁盘半径的主要物理效应，其中光学深度降至临界值以下。
A luminous body embedded in an accretion disk can generate asymmetric density perturbations that lead to a net torque and thus orbital migration of the body. Linear theory has shown that this heating torque gives rise to a migration term linear in the body's mass that can oppose or even reverse that arising from the sum of gravitational Lindblad and co-orbital torques. We use high-resolution local simulations in an unstratified disk to assess the accuracy and domain of applicability of the linear theory. We find agreement between analytic and simulation results to better than 10\% in the appropriate regime (low luminosity, low thermal conductivity), but measure deviations in the non-linear (high luminosity) regime and in the high thermal conductivity regime. In the non-linear regime, linear theory overpredicts the acceleration due to the heating torque, which we find to be due to the neglect of non-linear terms in the heat flux. In the high thermal conductivity regime linear theory underpredicts the acceleration, although here both non-linear and computational constraints play a role. We discuss the impact of the heating torque for the evolution of low-mass planets in protoplanetary disks, and for massive stars or accreting compact objects embedded in AGN disks. For the latter case, we show that the thermal torque is likely to be the dominant physical effect at disk radii where the optical depth drops below a critical value.
