标题： 激波绝热吸积流中的非轴对称不稳定性 显示英文标题

标题： Non-axisymmetric instabilities in shocked adiabatic accretion flows

摘要： 我们研究了绝热极限下单向黑洞的激波吸积流的线性稳定性。 我们的线性分析和数值计算表明，尽管激波后的减速效应，激波通常对非轴对称扰动是不稳定的。 Molteni、Tóth 和 Kuznetsov 的模拟结果可以通过我们的线性本征模很好地解释。 这种不稳定性机制被证实基于柯旋转半径与激波之间的声波循环。 我们得到了一个解析公式，可以从流的物理参数计算振荡周期。 我们认为，在具有角动量的吸积流中，准周期振荡应该是一种普遍现象。 显示英文摘要

摘要： We investigate the linear stability of a shocked accretion flow onto a black hole in the adiabatic limit. Our linear analyses and numerical calculations show that, despite the post-shock deceleration, the shock is generally unstable to non-axisymmetric perturbations. The simulation results of Molteni, T\'oth & Kuznetsov can be well explained by our linear eigenmodes. The mechanism of this instability is confirmed to be based on the cycle of acoustic waves between the corotation radius and the shock. We obtain an analytical formula to calculate the oscillation period from the physical parameters of the flow. We argue that the quasi-periodic oscillation should be a common phenomenon in accretion flows with angular momentum.