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.

中文翻译：

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吸积盘中发光体加热扭矩的局部模拟

嵌入吸积盘中的发光体会产生不对称的密度扰动，导致净扭矩，从而导致物体的轨道迁移。线性理论表明，这种加热扭矩会产生一个与身体质量呈线性关系的迁移项，它可以对抗甚至逆转由引力 Lindblad 和共轨扭矩之和引起的迁移项。我们在未分层的圆盘中使用高分辨率局部模拟来评估线性理论的准确性和适用范围。我们发现在适当的区域（低光度、低热导率）下，分析和模拟结果之间的一致性优于 10\%，但测量非线性（高光度）区域和高热导率区域的偏差。在非线性状态下，线性理论高估了由加热扭矩引起的加速度，我们发现这是由于忽略了热通量中的非线性项。在高热导率范围内，线性理论低估了加速度，尽管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行星盘中低质量行星演化的影响，以及对嵌入 AGN 盘中的大质量恒星或吸积致密物体的影响。对于后一种情况，我们表明热扭矩可能是光学深度低于临界值的磁盘半径处的主要物理效应。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行星盘中低质量行星演化的影响，以及对嵌入 AGN 盘中的大质量恒星或吸积致密物体的影响。对于后一种情况，我们表明热扭矩可能是光学深度低于临界值的磁盘半径处的主要物理效应。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行星盘中低质量行星演化的影响，以及对嵌入 AGN 盘中的大质量恒星或吸积致密物体的影响。对于后一种情况，我们表明热扭矩可能是光学深度低于临界值的磁盘半径处的主要物理效应。