论文标题
热不稳定性重新审视
Thermal instability revisited
论文作者
论文摘要
使用与Whitham的波浪层次结构理论相关的方法重复了场对热不稳定性的线性分析，该方法比原始分析以更清晰的方式提出了与物理相关的参数。它也用于非平衡状态的稳定性，我们表明，对于冲击后面的气体冷却，通常的分析仅对能够触发过渡到冷阶段的冲击有效。可以很容易地包括一个磁场，我们表明这不会改变稳定性标准。通过考虑稳定的冲击溶液，我们表明几乎所有合理的初始条件都导致平衡曲线不稳定部分的磁性状态。这些结果用于分析扰动稳态冲击溶液的数值计算以及与温云相互作用的冲击。
Field's linear analysis of thermal instability is repeated using methods related to Whitham's theory of wave hierarchies, which brings out the physically relevant parameters in a much clearer way than in the original analysis. It is also used for the stability of non-equilibrium states and we show that for gas cooling behind a shock, the usual analysis is only quantitatively valid for shocks that are just able to trigger a transition to the cold phase. A magnetic field can readily be included and we show that this does not change the stability criteria. By considering steady shock solutions, we show that almost all plausible initial conditions lead to a magnetically dominated state on the unstable part of the equilibrium curve. These results are used to analyse numerical calculations of perturbed steady shock solutions and of shocks interacting with a warm cloud.
